1
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Figueroa GB, D'souza S, Pereira HS, Vasudeva G, Figueroa SB, Robinson ZE, Badmalia MD, Meier-Stephenson V, Corcoran JA, van Marle G, Ni Y, Urban S, Coffin CS, Patel TR. Development of a single-domain antibody to target a G-quadruplex located on the hepatitis B virus covalently closed circular DNA genome. J Med Virol 2024; 96:e29692. [PMID: 38804172 DOI: 10.1002/jmv.29692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 04/22/2024] [Accepted: 05/14/2024] [Indexed: 05/29/2024]
Abstract
To achieve a virological cure for hepatitis B virus (HBV), innovative strategies are required to target the covalently closed circular DNA (cccDNA) genome. Guanine-quadruplexes (G4s) are a secondary structure that can be adopted by DNA and play a significant role in regulating viral replication, transcription, and translation. Antibody-based probes and small molecules have been developed to study the role of G4s in the context of the human genome, but none have been specifically made to target G4s in viral infection. Herein, we describe the development of a humanized single-domain antibody (S10) that can target a G4 located in the PreCore (PreC) promoter of the HBV cccDNA genome. MicroScale Thermophoresis demonstrated that S10 has a strong nanomolar affinity to the PreC G4 in its quadruplex form and a structural electron density envelope of the complex was determined using Small-Angle X-ray Scattering. Lentiviral transduction of S10 into HepG2-NTCP cells shows nuclear localization, and chromatin immunoprecipitation coupled with next-generation sequencing demonstrated that S10 can bind to the HBV PreC G4 present on the cccDNA. This research validates the existence of a G4 in HBV cccDNA and demonstrates that this DNA secondary structure can be targeted with high structural and sequence specificity using S10.
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Affiliation(s)
- Gerardo B Figueroa
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Simmone D'souza
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, Lethbridge, Alberta, Canada
- Department of Microbiology, Immunology and Infectious Diseases, Cumming School of Medicine, University of Calgary, Alberta, Canada
- Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Higor S Pereira
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Gunjan Vasudeva
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Sara B Figueroa
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Zachary E Robinson
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Maulik D Badmalia
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, Lethbridge, Alberta, Canada
- Li Ka Shing Institute of Virology, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Vanessa Meier-Stephenson
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, Lethbridge, Alberta, Canada
- Department of Microbiology, Immunology and Infectious Diseases, Cumming School of Medicine, University of Calgary, Alberta, Canada
- Li Ka Shing Institute of Virology, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Jennifer A Corcoran
- Department of Microbiology, Immunology and Infectious Diseases, Cumming School of Medicine, University of Calgary, Alberta, Canada
| | - Guido van Marle
- Department of Microbiology, Immunology and Infectious Diseases, Cumming School of Medicine, University of Calgary, Alberta, Canada
| | - Yi Ni
- Department of Infectious Diseases, Molecular Virology, University Hospital Heidelberg, Heidelberg, Germany
- German Center for Infection Research, Heidelberg University, Heidelberg, Germany
| | - Stephan Urban
- Department of Infectious Diseases, Molecular Virology, University Hospital Heidelberg, Heidelberg, Germany
- German Center for Infection Research, Heidelberg University, Heidelberg, Germany
| | - Carla S Coffin
- Department of Microbiology, Immunology and Infectious Diseases, Cumming School of Medicine, University of Calgary, Alberta, Canada
- Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Trushar R Patel
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, Lethbridge, Alberta, Canada
- Department of Microbiology, Immunology and Infectious Diseases, Cumming School of Medicine, University of Calgary, Alberta, Canada
- Li Ka Shing Institute of Virology, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, Alberta, Canada
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2
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Chinnam NB, Thapar R, Arvai AS, Sarker AH, Soll JM, Paul T, Syed A, Rosenberg DJ, Hammel M, Bacolla A, Katsonis P, Asthana A, Tsai MS, Ivanov I, Lichtarge O, Silverman RH, Mosammaparast N, Tsutakawa SE, Tainer JA. ASCC1 structures and bioinformatics reveal a novel Helix-Clasp-Helix RNA-binding motif linked to a two-histidine phosphodiesterase. J Biol Chem 2024; 300:107368. [PMID: 38750793 DOI: 10.1016/j.jbc.2024.107368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 05/07/2024] [Accepted: 05/09/2024] [Indexed: 06/06/2024] Open
Abstract
Activating signal co-integrator complex 1 (ASCC1) acts with ASCC-ALKBH3 complex in alkylation damage responses. ASCC1 uniquely combines two evolutionarily ancient domains: nucleotide-binding K-Homology (KH) (associated with regulating splicing, transcriptional, and translation) and two-histidine phosphodiesterase (PDE) (associated with hydrolysis of cyclic nucleotide phosphate bonds). Germline mutations link loss of ASCC1 function to spinal muscular atrophy with congenital bone fractures 2 (SMABF2). Herein analysis of The Cancer Genome Atlas (TCGA) suggests ASCC1 RNA overexpression in certain tumors correlates with poor survival, Signatures 29 and 3 mutations, and genetic instability markers. We determined crystal structures of Alvinella pompejana (Ap) ASCC1 and Human (Hs) PDE domain revealing high resolution details and features conserved over 500 million years of evolution. Extending understanding of the KH domain Gly-X-X-Gly sequence motif, we define a novel structural Helix-Clasp-Helix (HCH) nucleotide binding motif and show ASCC1 sequence-specific binding to CGCG-containing RNA. The V-shaped PDE nucleotide binding channel has two His-Φ-Ser/Thr-Φ (HXT) motifs (Φ being hydrophobic) positioned to initiate cyclic phosphate bond hydrolysis. A conserved atypical active-site histidine torsion angle implies a novel PDE substrate. Flexible active site loop and arginine-rich domain linker appear regulatory. Small angle X-ray scattering (SAXS) revealed aligned KH-PDE RNA binding sites with limited flexibility in solution. Quantitative evolutionary bioinformatic analyses of disease and cancer-associated mutations support implied functional roles for RNA binding, phosphodiesterase activity, and regulation. Collective results inform ASCC1 roles in transactivation and alkylation damage responses, its targeting by structure-based inhibitors, and how ASCC1 mutations may impact inherited disease and cancer.
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Affiliation(s)
- Naga Babu Chinnam
- Department of Molecular and Cellular Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States
| | - Roopa Thapar
- Department of Molecular and Cellular Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States
| | - Andrew S Arvai
- Integrative Structural & Computational Biology, The Scripps Research Institute, La Jolla, CA, 92037, United States
| | - Altaf H Sarker
- Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States
| | - Jennifer M Soll
- Department of Pathology and Immunology, Division of Laboratory and Genomic Medicine, Washington University in St. Louis, St. Louis, MO 63110, United States
| | - Tanmoy Paul
- Department Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA, 30302 United States
| | - Aleem Syed
- Department of Molecular and Cellular Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States
| | - Daniel J Rosenberg
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States
| | - Michal Hammel
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States
| | - Albino Bacolla
- Department of Molecular and Cellular Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States
| | - Panagiotis Katsonis
- Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, United States
| | - Abhishek Asthana
- Department Cancer Biology, Cleveland Clinic Foundation, Lerner Research Institute, Cleveland, OH, 44195, United States
| | - Miaw-Sheue Tsai
- Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States
| | - Ivaylo Ivanov
- Department Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA, 30302 United States
| | - Olivier Lichtarge
- Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, United States
| | - Robert H Silverman
- Department Cancer Biology, Cleveland Clinic Foundation, Lerner Research Institute, Cleveland, OH, 44195, United States
| | - Nima Mosammaparast
- Department of Pathology and Immunology, Division of Laboratory and Genomic Medicine, Washington University in St. Louis, St. Louis, MO 63110, United States
| | - Susan E Tsutakawa
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States.
| | - John A Tainer
- Department of Molecular and Cellular Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, United States; Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States; Department of Cancer Biology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, United States.
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3
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Brosey CA, Link TM, Shen R, Moiani D, Burnett K, Hura GL, Jones DE, Tainer JA. Chemical screening by time-resolved X-ray scattering to discover allosteric probes. Nat Chem Biol 2024:10.1038/s41589-024-01609-1. [PMID: 38671223 DOI: 10.1038/s41589-024-01609-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Accepted: 03/20/2024] [Indexed: 04/28/2024]
Abstract
Drug discovery relies on efficient identification of small-molecule leads and their interactions with macromolecular targets. However, understanding how chemotypes impact mechanistically important conformational states often remains secondary among high-throughput discovery methods. Here, we present a conformational discovery pipeline integrating time-resolved, high-throughput small-angle X-ray scattering (TR-HT-SAXS) and classic fragment screening applied to allosteric states of the mitochondrial import oxidoreductase apoptosis-inducing factor (AIF). By monitoring oxidized and X-ray-reduced AIF states, TR-HT-SAXS leverages structure and kinetics to generate a multidimensional screening dataset that identifies fragment chemotypes allosterically stimulating AIF dimerization. Fragment-induced dimerization rates, quantified with time-resolved SAXS similarity analysis (kVR), capture structure-activity relationships (SAR) across the top-ranked 4-aminoquinoline chemotype. Crystallized AIF-aminoquinoline complexes validate TR-SAXS-guided SAR, supporting this conformational chemotype for optimization. AIF-aminoquinoline structures and mutational analysis reveal active site F482 as an underappreciated allosteric stabilizer of AIF dimerization. This conformational discovery pipeline illustrates TR-HT-SAXS as an effective technology for targeting chemical leads to important macromolecular states.
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Affiliation(s)
- Chris A Brosey
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
| | - Todd M Link
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Runze Shen
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Davide Moiani
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Kathryn Burnett
- MBIB Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Greg L Hura
- MBIB Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - Darin E Jones
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - John A Tainer
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
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4
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Zheng L, Zhou B, Yang Y, Zan B, Zhong B, Wu B, Feng Y, Liu Q, Hong L. Mn 2+-induced structural flexibility enhances the entire catalytic cycle and the cleavage of mismatches in prokaryotic argonaute proteins. Chem Sci 2024; 15:5612-5626. [PMID: 38638240 PMCID: PMC11023060 DOI: 10.1039/d3sc06221j] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 03/01/2024] [Indexed: 04/20/2024] Open
Abstract
Prokaryotic Argonaute (pAgo) proteins, a class of DNA/RNA-guided programmable endonucleases, have been extensively utilized in nucleic acid-based biosensors. The specific binding and cleavage of nucleic acids by pAgo proteins, which are crucial processes for their applications, are dependent on the presence of Mn2+ bound in the pockets, as verified through X-ray crystallography. However, a comprehensive understanding of how dissociated Mn2+ in the solvent affects the catalytic cycle, and its underlying regulatory role in this structure-function relationship, remains underdetermined. By combining experimental and computational methods, this study reveals that unbound Mn2+ in solution enhances the flexibility of diverse pAgo proteins. This increase in flexibility through decreasing the number of hydrogen bonds, induced by Mn2+, leads to higher affinity for substrates, thus facilitating cleavage. More importantly, Mn2+-induced structural flexibility increases the mismatch tolerance between guide-target pairs by increasing the conformational states, thereby enhancing the cleavage of mismatches. Further simulations indicate that the enhanced flexibility in linkers triggers conformational changes in the PAZ domain for recognizing various lengths of nucleic acids. Additionally, Mn2+-induced dynamic alterations of the protein cause a conformational shift in the N domain and catalytic sites towards their functional form, resulting in a decreased energy penalty for target release and cleavage. These findings demonstrate that the dynamic conformations of pAgo proteins, resulting from the presence of the unbound Mn2+ in solution, significantly promote the catalytic cycle of endonucleases and the tolerance of cleavage to mismatches. This flexibility enhancement mechanism serves as a general strategy employed by Ago proteins from diverse prokaryotes to accomplish their catalytic functions and provide useful information for Ago-based precise molecular diagnostics.
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Affiliation(s)
- Lirong Zheng
- Institute of Natural Sciences, Shanghai Jiao Tong University Shanghai 200240 China
- Department of Cell and Developmental Biology & Michigan Neuroscience Institute, University of Michigan Medical School 48105 Ann Arbor MI USA
| | - Bingxin Zhou
- Institute of Natural Sciences, Shanghai Jiao Tong University Shanghai 200240 China
- Shanghai National Center for Applied Mathematics (SJTU Center), Shanghai Jiao Tong University Shanghai 200240 China
| | - Yu Yang
- State Key Laboratory for Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University Shanghai 200240 China
| | - Bing Zan
- Institute of Natural Sciences, Shanghai Jiao Tong University Shanghai 200240 China
| | - Bozitao Zhong
- State Key Laboratory for Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University Shanghai 200240 China
| | - Banghao Wu
- State Key Laboratory for Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University Shanghai 200240 China
| | - Yan Feng
- State Key Laboratory for Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University Shanghai 200240 China
| | - Qian Liu
- State Key Laboratory for Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University Shanghai 200240 China
| | - Liang Hong
- Institute of Natural Sciences, Shanghai Jiao Tong University Shanghai 200240 China
- State Key Laboratory for Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University Shanghai 200240 China
- Shanghai National Center for Applied Mathematics (SJTU Center), Shanghai Jiao Tong University Shanghai 200240 China
- Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University Shanghai 200240 China
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5
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Dykeman-Bermingham PA, Bogen MP, Chittari SS, Grizzard SF, Knight AS. Tailoring Hierarchical Structure and Rare Earth Affinity of Compositionally Identical Polymers via Sequence Control. J Am Chem Soc 2024; 146:8607-8617. [PMID: 38470430 DOI: 10.1021/jacs.4c00440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
Macromolecule sequence, structure, and function are inherently intertwined. While well-established relationships exist in proteins, they are more challenging to define for synthetic polymer nanoparticles due to their molecular weight, sequence, and conformational dispersities. To explore the impact of sequence on nanoparticle structure, we synthesized a set of 16 compositionally identical, sequence-controlled polymers with distinct monomer patterning of dimethyl acrylamide and a bioinspired, structure-driving di(phenylalanine) acrylamide (FF). Sequence control was achieved through multiblock polymerizations, yielding unique ensembles of polymer sequences which were simulated by kinetic Monte Carlo simulations. Systematic analysis of the global (tertiary- and quaternary-like) structure in this amphiphilic copolymer series revealed the effect of multiple sequence descriptors: the number of domains, the hydropathy of terminal domains, and the patchiness (density) of FF within a domain, each of which impacted both chain collapse and the distribution of single- and multichain assemblies. Furthermore, both the conformational freedom of chain segments and local-scale, β-sheet-like interactions were sensitive to the patchiness of FF. To connect sequence, structure, and target function, we evaluated an additional series of nine sequence-controlled copolymers as sequestrants for rare earth elements (REEs) by incorporating a functional acrylic acid monomer into select polymer scaffolds. We identified key sequence variables that influence the binding affinity, capacity, and selectivity of the polymers for REEs. Collectively, these results highlight the potential of and boundaries of sequence control via multiblock polymerizations to drive primary sequence ensembles hierarchical structures, and ultimately the functionality of compositionally identical polymeric materials.
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Affiliation(s)
- Peter A Dykeman-Bermingham
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Matthew P Bogen
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Supraja S Chittari
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Savannah F Grizzard
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Abigail S Knight
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
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6
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Tariq D, Maurici N, Bartholomai BM, Chandrasekaran S, Dunlap JC, Bah A, Crane BR. Phosphorylation, disorder, and phase separation govern the behavior of Frequency in the fungal circadian clock. eLife 2024; 12:RP90259. [PMID: 38526948 PMCID: PMC10963029 DOI: 10.7554/elife.90259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/27/2024] Open
Abstract
Circadian clocks are composed of transcription-translation negative feedback loops that pace rhythms of gene expression to the diurnal cycle. In the filamentous fungus Neurospora crassa, the proteins Frequency (FRQ), the FRQ-interacting RNA helicase (FRH), and Casein-Kinase I (CK1) form the FFC complex that represses expression of genes activated by the white-collar complex (WCC). FRQ orchestrates key molecular interactions of the clock despite containing little predicted tertiary structure. Spin labeling and pulse-dipolar electron spin resonance spectroscopy provide domain-specific structural insights into the 989-residue intrinsically disordered FRQ and the FFC. FRQ contains a compact core that associates and organizes FRH and CK1 to coordinate their roles in WCC repression. FRQ phosphorylation increases conformational flexibility and alters oligomeric state, but the changes in structure and dynamics are non-uniform. Full-length FRQ undergoes liquid-liquid phase separation (LLPS) to sequester FRH and CK1 and influence CK1 enzymatic activity. Although FRQ phosphorylation favors LLPS, LLPS feeds back to reduce FRQ phosphorylation by CK1 at higher temperatures. Live imaging of Neurospora hyphae reveals FRQ foci characteristic of condensates near the nuclear periphery. Analogous clock repressor proteins in higher organisms share little position-specific sequence identity with FRQ; yet, they contain amino acid compositions that promote LLPS. Hence, condensate formation may be a conserved feature of eukaryotic clocks.
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Affiliation(s)
- Daniyal Tariq
- Department of Chemistry & Chemical Biology, Cornell UniversityIthacaUnited States
| | - Nicole Maurici
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical UniversitySyracuseUnited States
| | - Bradley M Bartholomai
- Department of Molecular and Systems Biology, Geisel School of Medicine at DartmouthHanoverUnited States
| | | | - Jay C Dunlap
- Department of Molecular and Systems Biology, Geisel School of Medicine at DartmouthHanoverUnited States
| | - Alaji Bah
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical UniversitySyracuseUnited States
| | - Brian R Crane
- Department of Chemistry & Chemical Biology, Cornell UniversityIthacaUnited States
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7
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Hu Q, Botuyan MV, Mer G. Identification of a conserved α-helical domain at the N terminus of human DNA methyltransferase 1. J Biol Chem 2024; 300:105775. [PMID: 38382673 PMCID: PMC10950863 DOI: 10.1016/j.jbc.2024.105775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 02/03/2024] [Accepted: 02/15/2024] [Indexed: 02/23/2024] Open
Abstract
In vertebrates, DNA methyltransferase 1 (DNMT1) contributes to preserving DNA methylation patterns, ensuring the stability and heritability of epigenetic marks important for gene expression regulation and the maintenance of cellular identity. Previous structural studies have elucidated the catalytic mechanism of DNMT1 and its specific recognition of hemimethylated DNA. Here, using solution nuclear magnetic resonance spectroscopy and small-angle X-ray scattering, we demonstrate that the N-terminal region of human DNMT1, while flexible, encompasses a conserved globular domain with a novel α-helical bundle-like fold. This work expands our understanding of the structure and dynamics of DNMT1 and provides a structural framework for future functional studies in relation with this new domain.
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Affiliation(s)
- Qi Hu
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, USA
| | - Maria Victoria Botuyan
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, USA
| | - Georges Mer
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, USA; Department of Cancer Biology, Mayo Clinic, Rochester, Minnesota, USA.
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8
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Baral R, Ho K, Ramasamy PK, Hopkins JB, Watkins MB, LaRussa S, Caban-Penix S, Calderone LA, Bradshaw N. A General Mechanism for the General Stress Response in Bacteria. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.16.580724. [PMID: 38405867 PMCID: PMC10889023 DOI: 10.1101/2024.02.16.580724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Bacteria have a widely conserved General Stress Response (GSR) that allows them to survive adverse environmental conditions. However, because the signaling proteins that initiate the GSR have evolved to respond to a vast range of species-specific signals, we lack a general understanding of how they are controlled. Here, we determined the molecular mechanism by which a member of the PPM family of protein serine/threonine phosphatases, RsbU, activates the GSR in B. subtilis. It was known that the phosphatase activity of RsbU is activated through interaction with a partner protein, RsbT, when it is released from a megadalton stress-sensing complex upon environmental stress, but how RsbT activates RsbU was not understood. Here we report that RsbT binds an otherwise flexible linker of RsbU to dimerize and activate its phosphatase domains through a conserved allosteric switch element. Conformational flexibility of the homologous linker was known to control activity of the E. coli GSR-activating protein (RssB), which lacks phosphatase activity and functions as a protease adapter protein, suggesting a unifying model for GSR activation across bacterial phyla. Furthermore, and as we now show, the crossing α-helical conformation of RsbU linkers in the active dimeric state is similar to that predicted for paralogous bacterial phosphatases with diverse N-terminal sensory domains, and to linkers known to control the activity of GGDEF diguanylate cyclases and histidine kinases. We propose that this shared regulatory mechanism provides a modularly exchangeable toolkit for bacteria to recognize diverse environmental signals.
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Affiliation(s)
- Rishika Baral
- Department of Biochemistry, Brandeis University, Waltham, Massachusetts, USA
- Graduate program in Biochemistry and Biophysics, Brandeis University, Waltham, Massachusetts, USA
| | - Kristin Ho
- Department of Biochemistry, Brandeis University, Waltham, Massachusetts, USA
| | - Prem K. Ramasamy
- Department of Biochemistry, Brandeis University, Waltham, Massachusetts, USA
| | - Jesse B. Hopkins
- Biophysics Collaborative Access Team (BioCAT), Department of Physics, Illinois Institute of Technology, Chicago, Illinois, USA
| | - Maxwell B. Watkins
- Biophysics Collaborative Access Team (BioCAT), Department of Biology, Illinois Institute of Technology, Chicago, Illinois, USA
| | - Salvatore LaRussa
- Department of Biochemistry, Brandeis University, Waltham, Massachusetts, USA
- Graduate program in Biochemistry and Biophysics, Brandeis University, Waltham, Massachusetts, USA
| | - Suhaily Caban-Penix
- Department of Biochemistry, Brandeis University, Waltham, Massachusetts, USA
- Graduate program in Molecular and Cell Biology, Brandeis University, Waltham, Massachusetts, USA
| | - Logan A. Calderone
- Department of Biochemistry, Brandeis University, Waltham, Massachusetts, USA
- Graduate program in Biochemistry and Biophysics, Brandeis University, Waltham, Massachusetts, USA
| | - Niels Bradshaw
- Department of Biochemistry, Brandeis University, Waltham, Massachusetts, USA
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9
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Ujfalusi-Pozsonyi K, Bódis E, Nyitrai M, Kengyel A, Telek E, Pécsi I, Fekete Z, Varnyuné Kis-Bicskei N, Mas C, Moussaoui D, Pernot P, Tully MD, Weik M, Schirò G, Kapetanaki SM, Lukács A. ATP-dependent conformational dynamics in a photoactivated adenylate cyclase revealed by fluorescence spectroscopy and small-angle X-ray scattering. Commun Biol 2024; 7:147. [PMID: 38307988 PMCID: PMC10837130 DOI: 10.1038/s42003-024-05842-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Accepted: 01/22/2024] [Indexed: 02/04/2024] Open
Abstract
Structural insights into the photoactivated adenylate cyclases can be used to develop new ways of controlling cellular cyclic adenosine monophosphate (cAMP) levels for optogenetic and other applications. In this work, we use an integrative approach that combines biophysical and structural biology methods to provide insight on the interaction of adenosine triphosphate (ATP) with the dark-adapted state of the photoactivated adenylate cyclase from the cyanobacterium Oscillatoria acuminata (OaPAC). A moderate affinity of the nucleotide for the enzyme was calculated and the thermodynamic parameters of the interaction have been obtained. Stopped-flow fluorescence spectroscopy and small-angle solution scattering have revealed significant conformational changes in the enzyme, presumably in the adenylate cyclase (AC) domain during the allosteric mechanism of ATP binding to OaPAC with small and large-scale movements observed to the best of our knowledge for the first time in the enzyme in solution upon ATP binding. These results are in line with previously reported drastic conformational changes taking place in several class III AC domains upon nucleotide binding.
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Affiliation(s)
- K Ujfalusi-Pozsonyi
- Department of Biophysics, Medical School, University of Pécs, 7624, Pécs, Hungary
| | - E Bódis
- Department of Biophysics, Medical School, University of Pécs, 7624, Pécs, Hungary
| | - M Nyitrai
- Department of Biophysics, Medical School, University of Pécs, 7624, Pécs, Hungary
| | - A Kengyel
- Department of Biophysics, Medical School, University of Pécs, 7624, Pécs, Hungary
| | - E Telek
- Department of Biophysics, Medical School, University of Pécs, 7624, Pécs, Hungary
| | - I Pécsi
- Department of Biophysics, Medical School, University of Pécs, 7624, Pécs, Hungary
| | - Z Fekete
- Department of Biophysics, Medical School, University of Pécs, 7624, Pécs, Hungary
| | | | - C Mas
- Univ. Grenoble Alpes, CNRS, CEA, EMBL, ISBG, F-38000, Grenoble, France
| | - D Moussaoui
- European Synchrotron Radiation Facility (ESRF), Grenoble, France
| | - P Pernot
- European Synchrotron Radiation Facility (ESRF), Grenoble, France
| | - M D Tully
- European Synchrotron Radiation Facility (ESRF), Grenoble, France
| | - M Weik
- Institut de Biologie Structurale (IBS), Université Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - G Schirò
- Institut de Biologie Structurale (IBS), Université Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - S M Kapetanaki
- Institut de Biologie Structurale (IBS), Université Grenoble Alpes, CEA, CNRS, Grenoble, France.
- Department of Biophysics, Medical School, University of Pécs, 7624, Pécs, Hungary.
| | - A Lukács
- Department of Biophysics, Medical School, University of Pécs, 7624, Pécs, Hungary.
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10
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Murray D, Ge X, Schut GJ, Rosenberg DJ, Hammel M, Bierma JC, Hille R, Adams MWW, Hura GL. Correlating Conformational Equilibria with Catalysis in the Electron Bifurcating EtfABCX of Thermotoga maritima. Biochemistry 2024; 63:128-140. [PMID: 38013433 PMCID: PMC10765413 DOI: 10.1021/acs.biochem.3c00472] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 11/09/2023] [Accepted: 11/10/2023] [Indexed: 11/29/2023]
Abstract
Electron bifurcation (BF) is an evolutionarily ancient energy coupling mechanism in anaerobes, whose associated enzymatic machinery remains enigmatic. In BF-flavoenzymes, a chemically high-potential electron forms in a thermodynamically favorable fashion by simultaneously dropping the potential of a second electron before its donation to physiological acceptors. The cryo-EM and spectroscopic analyses of the BF-enzyme Fix/EtfABCX from Thermotoga maritima suggest that the BF-site contains a special flavin-adenine dinucleotide and, upon its reduction with NADH, a low-potential electron transfers to ferredoxin and a high-potential electron reduces menaquinone. The transfer of energy from high-energy intermediates must be carefully orchestrated conformationally to avoid equilibration. Herein, anaerobic size exclusion-coupled small-angle X-ray scattering (SEC-SAXS) shows that the Fix/EtfAB heterodimer subcomplex, which houses BF- and electron transfer (ET)-flavins, exists in a conformational equilibrium of compacted and extended states between flavin-binding domains, the abundance of which is impacted by reduction and NAD(H) binding. The conformations identify dynamics associated with the T. maritima enzyme and also recapitulate states identified in static structures of homologous BF-flavoenzymes. Reduction of Fix/EtfABCX's flavins alone is insufficient to elicit domain movements conducive to ET but requires a structural "trigger" induced by NAD(H) binding. Models show that Fix/EtfABCX's superdimer exists in a combination of states with respect to its BF-subcomplexes, suggesting a cooperative mechanism between supermonomers for optimizing catalysis. The correlation of conformational states with pathway steps suggests a structural means with which Fix/EtfABCX may progress through its catalytic cycle. Collectively, these observations provide a structural framework for tracing Fix/EtfABCX's catalysis.
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Affiliation(s)
- Daniel
T. Murray
- Molecular
Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Xiaoxuan Ge
- Department
of Biochemistry and Molecular Biology, University
of Georgia, Athens, Georgia 30602, United States
| | - Gerrit J. Schut
- Department
of Biochemistry and Molecular Biology, University
of Georgia, Athens, Georgia 30602, United States
| | - Daniel J. Rosenberg
- Molecular
Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Linac
Coherent Light Source, SLAC National Accelerator
Laboratory, Menlo
Park, California 94025, United States
| | - Michal Hammel
- Molecular
Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Jan C. Bierma
- Molecular
Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Russ Hille
- Department
of Biochemistry, University of California,
Riverside, Riverside, California 92521, United States
| | - Michael W. W. Adams
- Department
of Biochemistry and Molecular Biology, University
of Georgia, Athens, Georgia 30602, United States
| | - Greg L. Hura
- Molecular
Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Chemistry
and Biochemistry Department, University
of California, Santa Cruz, Santa
Cruz, California 95064, United States
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11
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Raveh B, Eliasian R, Rashkovits S, Russel D, Hayama R, Sparks SE, Singh D, Lim R, Villa E, Rout MP, Cowburn D, Sali A. Integrative spatiotemporal map of nucleocytoplasmic transport. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.31.573409. [PMID: 38260487 PMCID: PMC10802240 DOI: 10.1101/2023.12.31.573409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
The Nuclear Pore Complex (NPC) facilitates rapid and selective nucleocytoplasmic transport of molecules as large as ribosomal subunits and viral capsids. It is not clear how key emergent properties of this transport arise from the system components and their interactions. To address this question, we constructed an integrative coarse-grained Brownian dynamics model of transport through a single NPC, followed by coupling it with a kinetic model of Ran-dependent transport in an entire cell. The microscopic model parameters were fitted to reflect experimental data and theoretical information regarding the transport, without making any assumptions about its emergent properties. The resulting reductionist model is validated by reproducing several features of transport not used for its construction, such as the morphology of the central transporter, rates of passive and facilitated diffusion as a function of size and valency, in situ radial distributions of pre-ribosomal subunits, and active transport rates for viral capsids. The model suggests that the NPC functions essentially as a virtual gate whose flexible phenylalanine-glycine (FG) repeat proteins raise an entropy barrier to diffusion through the pore. Importantly, this core functionality is greatly enhanced by several key design features, including 'fuzzy' and transient interactions, multivalency, redundancy in the copy number of FG nucleoporins, exponential coupling of transport kinetics and thermodynamics in accordance with the transition state theory, and coupling to the energy-reliant RanGTP concentration gradient. These design features result in the robust and resilient rate and selectivity of transport for a wide array of cargo ranging from a few kilodaltons to megadaltons in size. By dissecting these features, our model provides a quantitative starting point for rationally modulating the transport system and its artificial mimics.
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12
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Walia N, Murray DT, Garg Y, He H, Weiss KL, Nagy G, Elizabeth Stroupe M. Domain crossover in the reductase subunit of NADPH-dependent assimilatory sulfite reductase. J Struct Biol 2023; 215:108028. [PMID: 37704014 DOI: 10.1016/j.jsb.2023.108028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 09/08/2023] [Accepted: 09/10/2023] [Indexed: 09/15/2023]
Abstract
NADPH-dependent assimilatory sulfite reductase (SiR) from Escherichia coli performs a six-electron reduction of sulfite to the bioavailable sulfide. SiR is composed of a flavoprotein (SiRFP) reductase subunit and a hemoprotein (SiRHP) oxidase subunit. There is no known high-resolution structure of SiR or SiRFP, thus we do not yet fully understand how the subunits interact to perform their chemistry. Here, we used small-angle neutron scattering to understand the impact of conformationally restricting the highly mobile SiRFP octamer into an electron accepting (closed) or electron donating (open) conformation, showing that SiR remains active, flexible, and asymmetric even with these conformational restrictions. From these scattering data, we model the first solution structure of SiRFP. Further, computational modeling of the N-terminal 52 amino acids that are responsible for SiRFP oligomerization suggests an eight-helical bundle tethers together the SiRFP subunits to form the SiR core. Finally, mass spectrometry analysis of the closed SiRFP variant show that SiRFP is capable of inter-molecular domain crossover, in which the electron donating domain from one polypeptide is able to interact directly with the electron accepting domain of another polypeptide. This structural characterization suggests that SiR performs its high-volume electron transfer through both inter- and intramolecular pathways between SiRFP domains and, thus, cis or trans transfer from reductase to oxidase subunits. Such highly redundant potential for electron transfer makes this system a potential target for designing synthetic enzymes.
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Affiliation(s)
- Nidhi Walia
- Department of Biological Science, Florida State University, 91 Chieftain Way, Tallahassee, FL 32306, USA; Institute of Molecular Biophysics, Florida State University, 91 Chieftain Way, Tallahassee, FL 32306, USA
| | - Daniel T Murray
- Department of Biological Science, Florida State University, 91 Chieftain Way, Tallahassee, FL 32306, USA; Institute of Molecular Biophysics, Florida State University, 91 Chieftain Way, Tallahassee, FL 32306, USA; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, USA(1)
| | - Yashika Garg
- Department of Biological Science, Florida State University, 91 Chieftain Way, Tallahassee, FL 32306, USA; Institute of Molecular Biophysics, Florida State University, 91 Chieftain Way, Tallahassee, FL 32306, USA
| | - Huan He
- Institute of Molecular Biophysics, Florida State University, 91 Chieftain Way, Tallahassee, FL 32306, USA; Translational Science Laboratory, College of Medicine, 1115 West Call Street, Tallahassee, FL 32306, USA
| | - Kevin L Weiss
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Gergely Nagy
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - M Elizabeth Stroupe
- Department of Biological Science, Florida State University, 91 Chieftain Way, Tallahassee, FL 32306, USA; Institute of Molecular Biophysics, Florida State University, 91 Chieftain Way, Tallahassee, FL 32306, USA.
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13
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Raviv U, Asor R, Shemesh A, Ginsburg A, Ben-Nun T, Schilt Y, Levartovsky Y, Ringel I. Insight into structural biophysics from solution X-ray scattering. J Struct Biol 2023; 215:108029. [PMID: 37741561 DOI: 10.1016/j.jsb.2023.108029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 08/09/2023] [Accepted: 09/18/2023] [Indexed: 09/25/2023]
Abstract
The current challenges of structural biophysics include determining the structure of large self-assembled complexes, resolving the structure of ensembles of complex structures and their mass fraction, and unraveling the dynamic pathways and mechanisms leading to the formation of complex structures from their subunits. Modern synchrotron solution X-ray scattering data enable simultaneous high-spatial and high-temporal structural data required to address the current challenges of structural biophysics. These data are complementary to crystallography, NMR, and cryo-TEM data. However, the analysis of solution scattering data is challenging; hence many different analysis tools, listed in the SAS Portal (http://smallangle.org/), were developed. In this review, we start by briefly summarizing classical X-ray scattering analyses providing insight into fundamental structural and interaction parameters. We then describe recent developments, integrating simulations, theory, and advanced X-ray scattering modeling, providing unique insights into the structure, energetics, and dynamics of self-assembled complexes. The structural information is essential for understanding the underlying physical chemistry principles leading to self-assembled supramolecular architectures and computational structural refinement.
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Affiliation(s)
- Uri Raviv
- Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 9190401, Israel; The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 9190401, Israel.
| | - Roi Asor
- Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 9190401, Israel
| | - Asaf Shemesh
- Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 9190401, Israel
| | - Avi Ginsburg
- Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 9190401, Israel
| | - Tal Ben-Nun
- Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 9190401, Israel
| | - Yaelle Schilt
- Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 9190401, Israel
| | - Yehonatan Levartovsky
- Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 9190401, Israel
| | - Israel Ringel
- Institute for Drug Research, School of Pharmacy, The Hebrew University of Jerusalem, 9112102 Jerusalem, Israel
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14
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Asor R, Singaram SW, Levi-Kalisman Y, Hagan MF, Raviv U. Effect of ionic strength on the assembly of simian vacuolating virus capsid protein around poly(styrene sulfonate). THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2023; 46:107. [PMID: 37917241 DOI: 10.1140/epje/s10189-023-00363-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 10/09/2023] [Indexed: 11/04/2023]
Abstract
Virus-like particles (VLPs) are noninfectious nanocapsules that can be used for drug delivery or vaccine applications. VLPs can be assembled from virus capsid proteins around a condensing agent, such as RNA, DNA, or a charged polymer. Electrostatic interactions play an important role in the assembly reaction. VLPs assemble from many copies of capsid protein, with a combinatorial number of intermediates. Hence, the mechanism of the reaction is poorly understood. In this paper, we combined solution small-angle X-ray scattering (SAXS), cryo-transmission electron microscopy (TEM), and computational modeling to determine the effect of ionic strength on the assembly of Simian Vacuolating Virus 40 (SV40)-like particles. We mixed poly(styrene sulfonate) with SV40 capsid protein pentamers at different ionic strengths. We then characterized the assembly product by SAXS and cryo-TEM. To analyze the data, we performed Langevin dynamics simulations using a coarse-grained model that revealed incomplete, asymmetric VLP structures consistent with the experimental data. We found that close to physiological ionic strength, [Formula: see text] VLPs coexisted with VP1 pentamers. At lower or higher ionic strengths, incomplete particles coexisted with pentamers and [Formula: see text] particles. Including the simulated structures was essential to explain the SAXS data in a manner that is consistent with the cryo-TEM images.
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Affiliation(s)
- Roi Asor
- Institute of Chemistry and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, 9190401, Jerusalem, Israel
| | - Surendra W Singaram
- Department of Physics, Brandeis University, 415 South Street, Waltham, 02453, MA, USA
| | - Yael Levi-Kalisman
- Institute of Life Sciences and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, 9190401, Jerusalem, Israel
| | - Michael F Hagan
- Department of Physics, Brandeis University, 415 South Street, Waltham, 02453, MA, USA.
| | - Uri Raviv
- Institute of Chemistry and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, 9190401, Jerusalem, Israel.
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15
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Petrvalska O, Honzejkova K, Koupilova N, Herman P, Obsilova V, Obsil T. 14-3-3 protein inhibits CaMKK1 by blocking the kinase active site with its last two C-terminal helices. Protein Sci 2023; 32:e4805. [PMID: 37817008 PMCID: PMC10588359 DOI: 10.1002/pro.4805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 10/04/2023] [Accepted: 10/08/2023] [Indexed: 10/12/2023]
Abstract
Ca2+ /CaM-dependent protein kinase kinases 1 and 2 (CaMKK1 and CaMKK2) phosphorylate and enhance the catalytic activity of downstream kinases CaMKI, CaMKIV, and protein kinase B. Accordingly, CaMKK1 and CaMKK2 regulate key physiological and pathological processes, such as tumorigenesis, neuronal morphogenesis, synaptic plasticity, transcription factor activation, and cellular energy homeostasis, and promote cell survival. Both CaMKKs are partly inhibited by phosphorylation, which in turn triggers adaptor and scaffolding protein 14-3-3 binding. However, 14-3-3 binding only significantly affects CaMKK1 function. CaMKK2 activity remains almost unchanged after complex formation for reasons still unclear. Here, we aim at structurally characterizing CaMKK1:14-3-3 and CaMKK2:14-3-3 complexes by SAXS, H/D exchange coupled to MS, and fluorescence spectroscopy. The results revealed that complex formation suppresses the interaction of both phosphorylated CaMKKs with Ca2+ /CaM and affects the structure of their kinase domains and autoinhibitory segments. But these effects are much stronger on CaMKK1 than on CaMKK2 because the CaMKK1:14-3-3γ complex has a more compact and rigid structure in which the active site of the kinase domain directly interacts with the last two C-terminal helices of the 14-3-3γ protein, thereby inhibiting CaMKK1. In contrast, the CaMKK2:14-3-3 complex has a looser and more flexible structure, so 14-3-3 binding only negligibly affects the catalytic activity of CaMKK2. Therefore, Ca2+ /CaM binding suppression and the interaction of the kinase active site of CaMKK1 with the last two C-terminal helices of 14-3-3γ protein provide the structural basis for 14-3-3-mediated CaMKK1 inhibition.
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Affiliation(s)
- Olivia Petrvalska
- Department of Physical and Macromolecular Chemistry, Faculty of ScienceCharles UniversityPragueCzech Republic
- Institute of Physiology of the Czech Academy of Sciences, Laboratory of Structural Biology of Signaling ProteinsDivision BIOCEVVestecCzech Republic
| | - Karolina Honzejkova
- Department of Physical and Macromolecular Chemistry, Faculty of ScienceCharles UniversityPragueCzech Republic
| | - Nicola Koupilova
- Department of Physical and Macromolecular Chemistry, Faculty of ScienceCharles UniversityPragueCzech Republic
| | - Petr Herman
- Institute of Physics, Faculty of Mathematics and PhysicsCharles UniversityPragueCzech Republic
| | - Veronika Obsilova
- Institute of Physiology of the Czech Academy of Sciences, Laboratory of Structural Biology of Signaling ProteinsDivision BIOCEVVestecCzech Republic
| | - Tomas Obsil
- Department of Physical and Macromolecular Chemistry, Faculty of ScienceCharles UniversityPragueCzech Republic
- Institute of Physiology of the Czech Academy of Sciences, Laboratory of Structural Biology of Signaling ProteinsDivision BIOCEVVestecCzech Republic
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16
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Wang T, Coshic K, Badiee M, Aksimentiev A, Pollack L, Leung AKL. Length-dependent Intramolecular Coil-to-Globule Transition in Poly(ADP-ribose) Induced by Cations. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.25.564012. [PMID: 37961637 PMCID: PMC10634823 DOI: 10.1101/2023.10.25.564012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Poly(ADP-ribose) (PAR), as part of a post-translational modification, serves as a flexible scaffold for noncovalent protein binding. Such binding is influenced by PAR chain length through a mechanism yet to be elucidated. Structural insights have been elusive, partly due to the difficulties associated with synthesizing PAR chains of defined lengths. Here, we employ an integrated approach combining molecular dynamics (MD) simulations with small-angle X-ray scattering (SAXS) experiments, enabling us to identify highly heterogeneous ensembles of PAR conformers at two different, physiologically relevant lengths: PAR 15 and PAR 22 . Our findings reveal that numerous factors including backbone conformation, base stacking, and chain length contribute to determining the structural ensembles. We also observe length-dependent compaction of PAR upon the addition of small amounts of Mg 2+ ions, with the 22-mer exhibiting ADP-ribose bundles formed through local intramolecular coil-to-globule transitions. This study illuminates how such bundling could be instrumental in deciphering the length-dependent action of PAR. GRAPHICAL ABSTRACT
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17
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Hazra R, Roy D. Robustness of heteroaggregates involving hydrophobic cholesterol and its mimetics. Phys Chem Chem Phys 2023; 25:27230-27243. [PMID: 37791397 DOI: 10.1039/d3cp02174b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Exploring the self and cross aggregation affinity of cholesterol (CHL) and some of its lookalikes, e.g., cholesteryl hemisuccinate (CHM), campesterol (CAM) and arjunic acid (ARJ), provides crucial understanding towards the influence of weak forces in inducing mixed micellization through heteroaggregation. Strongly hydrophobic CHL, with a benchmark inclination towards aggregation, often forms detrimental plaques in crucial human organs that are fairly difficult to disintegrate. Traditionally known anti-dyslipidemic agents like CAM and ARJ are known to interact strongly with CHL in the gut when ingested. They further form mixed micelles along with the bile components and interfere with the CHL absorption across the epithelial cell layer of the intestine. Some invariant questions like how robust are the heteroaggregates formed between these mimetics and CHL are very important to appreciate the efficacy of such anti-dyslipidemic agents. In this work using molecular dynamics simulations and varied structural analysis, we characterize the heteroaggregates. Simulations indicate that CHL-CHM mixed assemblies are comparatively bigger and significantly stabilized by strong electrostatic and favourable vdW forces. Small and diffused CHL-ARJ aggregates are observed in our simulations with a not so favourable energetics, indicating a possible attenuation pathway of CHL aggregation in the presence of ARJ.
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Affiliation(s)
- Rituparna Hazra
- Department of Chemistry, Birla Institute of Technology and Science-Pilani, Hyderabad Campus, Jawahar Nagar, Kapra Mandal, Hyderabad, Telangana 500078, India.
| | - Durba Roy
- Department of Chemistry, Birla Institute of Technology and Science-Pilani, Hyderabad Campus, Jawahar Nagar, Kapra Mandal, Hyderabad, Telangana 500078, India.
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18
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Lu S, Ma Z, Qin L, Ding M, Wang Z, Liu J, Zhang R, Zhang Y, Dong G. Effect of molecular helical structure on self-growing and damping of single network κ-carrageenan hydrogel. Int J Biol Macromol 2023; 249:126082. [PMID: 37536410 DOI: 10.1016/j.ijbiomac.2023.126082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 07/14/2023] [Accepted: 07/29/2023] [Indexed: 08/05/2023]
Abstract
Molecular helical is ubiquitous in molecular structures, however, the impact of the structure on mechanical properties has yet to be extensively studied. In this study, we synthesized a single network κ-carrageenan (KC) hydrogel with the molecular double helix structure, and elucidated its unique self-enhancing and damping properties from a molecular structural perspective. During cycle tensile tests, the helical structure was stretched and entangled to form a directional arrangement, increasing the elastic modulus and achieving 'self-reinforcement'. Meanwhile, the molecular helices have a spring-like damping effect, allowing the hydrogel to dampen low-frequency noise while transmitting high-frequency signals. By utilizing the hydrogel to create electrodes for electrocardiogram (ECG) detection, we were able to effectively filter out noise generated by movements while retaining necessary signals. Our work thus presents a potential pathway bridging from microscopic molecular structure to macroscopic mechanical properties of materials.
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Affiliation(s)
- Shan Lu
- Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System, Institute of Design Science and Basic Components, Xi'an Jiaotong University, Xi'an 710049, China.
| | - Zeyu Ma
- Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System, Institute of Design Science and Basic Components, Xi'an Jiaotong University, Xi'an 710049, China.
| | - Liguo Qin
- Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System, Institute of Design Science and Basic Components, Xi'an Jiaotong University, Xi'an 710049, China.
| | - Mingwei Ding
- Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System, Institute of Design Science and Basic Components, Xi'an Jiaotong University, Xi'an 710049, China
| | - Zheng Wang
- Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System, Institute of Design Science and Basic Components, Xi'an Jiaotong University, Xi'an 710049, China.
| | - Jianbo Liu
- Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System, Institute of Design Science and Basic Components, Xi'an Jiaotong University, Xi'an 710049, China.
| | - Rui Zhang
- Xi'an Microelectronics Technology Institute, Xi'an 710054, China
| | - Yali Zhang
- Key Laboratory of Biomedical Information of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China.
| | - Guangneng Dong
- Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System, Institute of Design Science and Basic Components, Xi'an Jiaotong University, Xi'an 710049, China.
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19
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Mangini V, Grasso G, Belviso BD, Sciacca MFM, Lanza V, Caliandro R, Milardi D. Stretching the chains: the destabilizing impact of Cu 2+ and Zn 2+ ions on K48-linked diubiquitin. Dalton Trans 2023; 52:11835-11849. [PMID: 37581921 DOI: 10.1039/d3dt01815f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/16/2023]
Abstract
Ubiquitin signalling and metal homeostasis play key roles in controlling several physiological cellular activities, including protein trafficking and degradation. While some relationships between these two biochemical pathways have started to surface, our knowledge of their interplay remains limited. Here, we employ a variety of techniques, such as circular dichroism, differential scanning calorimetry, pressure perturbation calorimetry, fluorescence emission, SDS-PAGE, and small-angle X-ray scattering (SAXS) to evaluate the impact of Cu2+ and Zn2+ ions on the structure and stability of K48 linked diubiquitin (K48-Ub2), a simple model for polyubiquitin chains. The SAXS analysis results show that the structure of the metal-free protein is similar to that observed when the protein is bound to the E2 conjugating enzyme, lending support to the idea that the structure of unanchored K48-linked ubiquitin chains is sufficient for identification by conjugating enzymes without the need for an induced fit mechanism. Our results indicate that K48-Ub2 can coordinate up to four metal ions with both copper and zinc ions inducing slight changes to the secondary structure of the protein. However, we noted significant distinctions in their impacts on protein stability and overall architecture. Specifically, Cu2+ ions resulted in a destabilization of the protein structure, which facilitated the formation of dimer aggregates. Next, we observed a shift in the conformational dynamics of K48-Ub2 toward less compact and more flexible states upon metal ion binding, with Zn2+ inducing a more significant effect than Cu2+ ions. Our structural modelling study demonstrates that both metal ions induced perturbations in the K48-Ub2 structure, leading to the separation of the two monomers thus inhibiting interactions with E2 enzymes. In conclusion, the findings from this study enhance our comprehension of the mechanisms underlying Ub chains recognition. Moreover, they strengthen the notion that drug discovery initiatives aimed at targeting metal-mediated disruptions in Ub signaling hold great potential for treating a wide range of diseases that stem from abnormal protein accumulation.
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Affiliation(s)
- Vincenzo Mangini
- Istituto di Cristallografia - CNR sede di Bari, Via G. Amendola 122/O, 70126 Bari, Italy.
| | - Giulia Grasso
- Istituto di Cristallografia - CNR sede secondaria di Catania, Via P. Gaifami 18, 95126 Catania, Italy.
| | - Benny Danilo Belviso
- Istituto di Cristallografia - CNR sede di Bari, Via G. Amendola 122/O, 70126 Bari, Italy.
| | - Michele F M Sciacca
- Istituto di Cristallografia - CNR sede secondaria di Catania, Via P. Gaifami 18, 95126 Catania, Italy.
| | - Valeria Lanza
- Istituto di Cristallografia - CNR sede secondaria di Catania, Via P. Gaifami 18, 95126 Catania, Italy.
| | - Rocco Caliandro
- Istituto di Cristallografia - CNR sede di Bari, Via G. Amendola 122/O, 70126 Bari, Italy.
| | - Danilo Milardi
- Istituto di Cristallografia - CNR sede secondaria di Catania, Via P. Gaifami 18, 95126 Catania, Italy.
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20
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Cordoba JJ, Mullins EA, Salay LE, Eichman BF, Chazin WJ. Flexibility and distributive synthesis regulate RNA priming and handoff in human DNA polymerase α-primase. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.01.551538. [PMID: 37577606 PMCID: PMC10418221 DOI: 10.1101/2023.08.01.551538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
DNA replication in eukaryotes relies on the synthesis of a ~30-nucleotide RNA/DNA primer strand through the dual action of the heterotetrameric polymerase α-primase (pol-prim) enzyme. Synthesis of the 7-10-nucleotide RNA primer is regulated by the C-terminal domain of the primase regulatory subunit (PRIM2C) and is followed by intramolecular handoff of the primer to pol α for extension by ~20 nucleotides of DNA. Here we provide evidence that RNA primer synthesis is governed by a combination of the high affinity and flexible linkage of the PRIM2C domain and the low affinity of the primase catalytic domain (PRIM1) for substrate. Using a combination of small angle X-ray scattering and electron microscopy, we found significant variability in the organization of PRIM2C and PRIM1 in the absence and presence of substrate, and that the population of structures with both PRIM2C and PRIM1 in a configuration aligned for synthesis is low. Crosslinking was used to visualize the orientation of PRIM2C and PRIM1 when engaged by substrate as observed by electron microscopy. Microscale thermophoresis was used to measure substrate affinities for a series of pol-prim constructs, which showed that the PRIM1 catalytic domain does not bind the template or emergent RNA-primed templates with appreciable affinity. Together, these findings support a model of RNA primer synthesis in which generation of the nascent RNA strand and handoff of the RNA-primed template from primase to polymerase α is mediated by the high degree of inter-domain flexibility of pol-prim, the ready dissociation of PRIM1 from its substrate, and the much higher affinity of the POLA1cat domain of polymerase α for full-length RNA-primed templates.
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Affiliation(s)
- John J. Cordoba
- Chemical and Physical Biology Program, Vanderbilt University, Nashville, Tennessee, USA
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, USA
| | - Elwood A. Mullins
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, USA
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - Lauren E. Salay
- Chemical and Physical Biology Program, Vanderbilt University, Nashville, Tennessee, USA
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, USA
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA
| | - Brandt F. Eichman
- Chemical and Physical Biology Program, Vanderbilt University, Nashville, Tennessee, USA
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, USA
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA
| | - Walter J. Chazin
- Chemical and Physical Biology Program, Vanderbilt University, Nashville, Tennessee, USA
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, USA
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, USA
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21
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Nedić O, Penezić A, Minić S, Radomirović M, Nikolić M, Ćirković Veličković T, Gligorijević N. Food Antioxidants and Their Interaction with Human Proteins. Antioxidants (Basel) 2023; 12:antiox12040815. [PMID: 37107190 PMCID: PMC10135064 DOI: 10.3390/antiox12040815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 03/22/2023] [Accepted: 03/25/2023] [Indexed: 03/29/2023] Open
Abstract
Common to all biological systems and living organisms are molecular interactions, which may lead to specific physiological events. Most often, a cascade of events occurs, establishing an equilibrium between possibly competing and/or synergistic processes. Biochemical pathways that sustain life depend on multiple intrinsic and extrinsic factors contributing to aging and/or diseases. This article deals with food antioxidants and human proteins from the circulation, their interaction, their effect on the structure, properties, and function of antioxidant-bound proteins, and the possible impact of complex formation on antioxidants. An overview of studies examining interactions between individual antioxidant compounds and major blood proteins is presented with findings. Investigating antioxidant/protein interactions at the level of the human organism and determining antioxidant distribution between proteins and involvement in the particular physiological role is a very complex and challenging task. However, by knowing the role of a particular protein in certain pathology or aging, and the effect exerted by a particular antioxidant bound to it, it is possible to recommend specific food intake or resistance to it to improve the condition or slow down the process.
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Affiliation(s)
- Olgica Nedić
- Institute for the Application of Nuclear Energy, Department for Metabolism, University of Belgrade, Banatska 31b, 11080 Belgrade, Serbia
- Correspondence:
| | - Ana Penezić
- Institute for the Application of Nuclear Energy, Department for Metabolism, University of Belgrade, Banatska 31b, 11080 Belgrade, Serbia
| | - Simeon Minić
- Center of Excellence for Molecular Food Sciences, Department of Biochemistry, Faculty of Chemistry, University of Belgrade, 11000 Belgrade, Serbia
| | - Mirjana Radomirović
- Center of Excellence for Molecular Food Sciences, Department of Biochemistry, Faculty of Chemistry, University of Belgrade, 11000 Belgrade, Serbia
| | - Milan Nikolić
- Center of Excellence for Molecular Food Sciences, Department of Biochemistry, Faculty of Chemistry, University of Belgrade, 11000 Belgrade, Serbia
| | - Tanja Ćirković Veličković
- Center of Excellence for Molecular Food Sciences, Department of Biochemistry, Faculty of Chemistry, University of Belgrade, 11000 Belgrade, Serbia
- Serbian Academy of Sciences and Arts, Knez Mihailova 35, 11000 Belgrade, Serbia
| | - Nikola Gligorijević
- Institute for the Application of Nuclear Energy, Department for Metabolism, University of Belgrade, Banatska 31b, 11080 Belgrade, Serbia
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22
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Trastoy B, Du JJ, Cifuente JO, Rudolph L, García-Alija M, Klontz EH, Deredge D, Sultana N, Huynh CG, Flowers MW, Li C, Sastre DE, Wang LX, Corzana F, Mallagaray A, Sundberg EJ, Guerin ME. Mechanism of antibody-specific deglycosylation and immune evasion by Streptococcal IgG-specific endoglycosidases. Nat Commun 2023; 14:1705. [PMID: 36973249 PMCID: PMC10042849 DOI: 10.1038/s41467-023-37215-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Accepted: 03/03/2023] [Indexed: 03/29/2023] Open
Abstract
Bacterial pathogens have evolved intricate mechanisms to evade the human immune system, including the production of immunomodulatory enzymes. Streptococcus pyogenes serotypes secrete two multi-modular endo-β-N-acetylglucosaminidases, EndoS and EndoS2, that specifically deglycosylate the conserved N-glycan at Asn297 on IgG Fc, disabling antibody-mediated effector functions. Amongst thousands of known carbohydrate-active enzymes, EndoS and EndoS2 represent just a handful of enzymes that are specific to the protein portion of the glycoprotein substrate, not just the glycan component. Here, we present the cryoEM structure of EndoS in complex with the IgG1 Fc fragment. In combination with small-angle X-ray scattering, alanine scanning mutagenesis, hydrolytic activity measurements, enzyme kinetics, nuclear magnetic resonance and molecular dynamics analyses, we establish the mechanisms of recognition and specific deglycosylation of IgG antibodies by EndoS and EndoS2. Our results provide a rational basis from which to engineer novel enzymes with antibody and glycan selectivity for clinical and biotechnological applications.
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Affiliation(s)
- Beatriz Trastoy
- Structural Glycobiology Laboratory, Biocruces Health Research Institute, Barakaldo, Bizkaia, 48903, Spain.
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160, Derio, Spain.
- Ikerbasque, Basque Foundation for Science, 48009, Bilbao, Spain.
| | - Jonathan J Du
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Javier O Cifuente
- Structural Glycobiology Laboratory, Biocruces Health Research Institute, Barakaldo, Bizkaia, 48903, Spain
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160, Derio, Spain
| | - Lorena Rudolph
- University of Lübeck, Center of Structural and Cell Biology in Medicine (CSCM), Institute of Chemistry and Metabolomics, Ratzeburger Allee 160, 23562, Lübeck, Germany
| | - Mikel García-Alija
- Structural Glycobiology Laboratory, Biocruces Health Research Institute, Barakaldo, Bizkaia, 48903, Spain
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160, Derio, Spain
| | - Erik H Klontz
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Daniel Deredge
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD, 21201, USA
| | - Nazneen Sultana
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Chau G Huynh
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Maria W Flowers
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Chao Li
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, 20742, USA
| | - Diego E Sastre
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Lai-Xi Wang
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, 20742, USA
| | - Francisco Corzana
- Departamento Química and Centro de Investigación en Síntesis Quı́mica, Universidad de La Rioja, 26006, Rioja, Spain
| | - Alvaro Mallagaray
- University of Lübeck, Center of Structural and Cell Biology in Medicine (CSCM), Institute of Chemistry and Metabolomics, Ratzeburger Allee 160, 23562, Lübeck, Germany.
| | - Eric J Sundberg
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| | - Marcelo E Guerin
- Structural Glycobiology Laboratory, Biocruces Health Research Institute, Barakaldo, Bizkaia, 48903, Spain.
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160, Derio, Spain.
- Ikerbasque, Basque Foundation for Science, 48009, Bilbao, Spain.
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23
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Xue B, Lai Y, Liu Y, Li M, Li X, Yin P. The Counterion-Mediated Controllable Coacervation of Nano-Ions with Polyelectrolytes. J Colloid Interface Sci 2023; 641:853-860. [PMID: 36966574 DOI: 10.1016/j.jcis.2023.03.105] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 03/14/2023] [Accepted: 03/17/2023] [Indexed: 03/22/2023]
Abstract
Nano-ions can complex with polyelectrolytes for coacervates with hierarchical structures; however, the rational design of functional coacervations is still rare due to the poor understanding of their structure-property relationship from their complex interaction. Herein, 1 nm anionic metal oxide clusters, PW12O403-, with well-defined, mono-disperse structures are applied to complex with cationic polyelectrolyte and the system shows tunable coacervation via the alternation of counterions (H+ and Na+) of PW12O403-. Suggested from Fourier transform infrared spectroscopy (FT-IR) and isothermal titration studies, the interaction between PW12O403- and cationic polyelectrolytes can be modulated by the bridging effect of counterions via hydrogen bonding or ion-dipole interaction to carbonyl groups of polyelectrolytes. The condensed structures of the complexed coacervates are explored by small angle X-ray and neutron scattering techniques, respectively. The coacervate with H+ as counterions shows both crystallized and discrete PW12O403- clusters, with a loose polymer-cluster network in comparison to the system of Na+ which shows a dense packing structure with aggregated nano-ions filling the meshes of polyelectrolyte networks. The bridging effect of counterions helps understand the super-chaotropic effect observed in nano-ion system and provides avenues for the design of metal oxide cluster-based functional coacervates.
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24
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Watson JA, Pantier R, Jayachandran U, Chhatbar K, Alexander-Howden B, Kruusvee V, Prendecki M, Bird A, Cook AG. Structure of SALL4 zinc finger domain reveals link between AT-rich DNA binding and Okihiro syndrome. Life Sci Alliance 2023; 6:e202201588. [PMID: 36635047 PMCID: PMC9838217 DOI: 10.26508/lsa.202201588] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 12/19/2022] [Accepted: 12/20/2022] [Indexed: 01/13/2023] Open
Abstract
Spalt-like 4 (SALL4) maintains vertebrate embryonic stem cell identity and is required for the development of multiple organs, including limbs. Mutations in SALL4 are associated with Okihiro syndrome, and SALL4 is also a known target of thalidomide. SALL4 protein has a distinct preference for AT-rich sequences, recognised by a pair of zinc fingers at the C-terminus. However, unlike many characterised zinc finger proteins, SALL4 shows flexible recognition with many different combinations of AT-rich sequences being targeted. SALL4 interacts with the NuRD corepressor complex which potentially mediates repression of AT-rich genes. We present a crystal structure of SALL4 C-terminal zinc fingers with an AT-rich DNA sequence, which shows that SALL4 uses small hydrophobic and polar side chains to provide flexible recognition in the major groove. Missense mutations reported in patients that lie within the C-terminal zinc fingers reduced overall binding to DNA but not the preference for AT-rich sequences. Furthermore, these mutations altered association of SALL4 with AT-rich genomic sites, providing evidence that these mutations are likely pathogenic.
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Affiliation(s)
- James A Watson
- Wellcome Centre for Cell Biology, Max Born Crescent, Edinburgh, UK
| | - Raphaël Pantier
- Wellcome Centre for Cell Biology, Max Born Crescent, Edinburgh, UK
| | - Uma Jayachandran
- Wellcome Centre for Cell Biology, Max Born Crescent, Edinburgh, UK
| | - Kashyap Chhatbar
- Wellcome Centre for Cell Biology, Max Born Crescent, Edinburgh, UK
| | | | - Valdeko Kruusvee
- Wellcome Centre for Cell Biology, Max Born Crescent, Edinburgh, UK
| | - Michal Prendecki
- Wellcome Centre for Cell Biology, Max Born Crescent, Edinburgh, UK
| | - Adrian Bird
- Wellcome Centre for Cell Biology, Max Born Crescent, Edinburgh, UK
| | - Atlanta G Cook
- Wellcome Centre for Cell Biology, Max Born Crescent, Edinburgh, UK
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25
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Kaur G, Ren R, Hammel M, Horton JR, Yang J, Cao Y, He C, Lan F, Lan X, Blobel GA, Blumenthal RM, Zhang X, Cheng X. Allosteric autoregulation of DNA binding via a DNA-mimicking protein domain: a biophysical study of ZNF410-DNA interaction using small angle X-ray scattering. Nucleic Acids Res 2023; 51:1674-1686. [PMID: 36660822 PMCID: PMC9976917 DOI: 10.1093/nar/gkac1274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 12/19/2022] [Accepted: 12/27/2022] [Indexed: 01/21/2023] Open
Abstract
ZNF410 is a highly-conserved transcription factor, remarkable in that it recognizes a 15-base pair DNA element but has just a single responsive target gene in mammalian erythroid cells. ZNF410 includes a tandem array of five zinc-fingers (ZFs), surrounded by uncharacterized N- and C-terminal regions. Unexpectedly, full-length ZNF410 has reduced DNA binding affinity, compared to that of the isolated DNA binding ZF array, both in vitro and in cells. AlphaFold predicts a partially-folded N-terminal subdomain that includes a 30-residue long helix, preceded by a hairpin loop rich in acidic (aspartate/glutamate) and serine/threonine residues. This hairpin loop is predicted by AlphaFold to lie against the DNA binding interface of the ZF array. In solution, ZNF410 is a monomer and binds to DNA with 1:1 stoichiometry. Surprisingly, the single best-fit model for the experimental small angle X-ray scattering profile, in the absence of DNA, is the original AlphaFold model with the N-terminal long-helix and the hairpin loop occupying the ZF DNA binding surface. For DNA binding, the hairpin loop presumably must be displaced. After combining biophysical, biochemical, bioinformatic and artificial intelligence-based AlphaFold analyses, we suggest that the hairpin loop mimics the structure and electrostatics of DNA, and provides an additional mechanism, supplementary to sequence specificity, of regulating ZNF410 DNA binding.
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Affiliation(s)
- Gundeep Kaur
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Ren Ren
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Michal Hammel
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - John R Horton
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Jie Yang
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Yu Cao
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Chenxi He
- Shanghai Key Laboratory of Medical Epigenetics, International Laboratory of Medical Epigenetics and Metabolism, Ministry of Science and Technology, Institutes of Biomedical Sciences, Fudan University and Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Fei Lan
- Shanghai Key Laboratory of Medical Epigenetics, International Laboratory of Medical Epigenetics and Metabolism, Ministry of Science and Technology, Institutes of Biomedical Sciences, Fudan University and Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Xianjiang Lan
- Department of Systems Biology for Medicine, School of Basic Medical Sciences; Department of Liver Surgery and Transplantation, Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai 200032, China
- Division of Hematology, the Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Gerd A Blobel
- Division of Hematology, the Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Robert M Blumenthal
- Department of Medical Microbiology and Immunology, and Program in Bioinformatics, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA
| | - Xing Zhang
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Xiaodong Cheng
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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26
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Pedezzi R, Evangelista DE, da Rosa Garzon NG, de Oliveira Simões FA, de Oliveira AHC, Polikarpov I, Cabral H. Biochemical and biophysical properties of a recombinant serine peptidase from Purpureocillium lilacinum. Biophys Chem 2023; 296:106978. [PMID: 36827753 DOI: 10.1016/j.bpc.2023.106978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 02/16/2023] [Accepted: 02/17/2023] [Indexed: 02/22/2023]
Abstract
The industrial uses of peptidases have already been consolidated; however, their range of applications is increasing. Thus, the biochemical characterization of new peptidases could increase the range of their biotechnological applications. In silico analysis identified a gene encoding a putative serine peptidase from Purpureocillium lilacinum (Pl_SerPep), annotated as a cuticle-degrading enzyme. The Pl_SerPep gene product was expressed as a recombinant in a Komagataella phaffii (previously Pichia pastoris) expression system. The enzyme (rPl_SerPep) showed optimal pH and temperature of 8.0 and 60 °C, respectively. Moreover, rPl_SerPep has a higher thermal stability than the cuticle-degrading enzymes described elsewhere. The structural analysis indicated a conformational change in the rPl_SerPep secondary structure, which would allow an increase in catalytic activity at 60 °C. Komagataella phaffii secretes rPl_SerPep with the pro peptide in its inactive form. Low-resolution small-angle X-ray scattering (SAXS) analysis showed little mobility of the pro peptide portion, which indicates the apparent stability of the inactive form of the enzyme. The presence of 20 mM guanidine in the reaction resulted in the maintenance of activity, which was apparently a consequence of pro peptide structure flexibilization.
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Affiliation(s)
- Rafael Pedezzi
- Department of Pharmaceutical Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto 14040-903, Brazil
| | - Danilo Elton Evangelista
- Instituto de Física de São Carlos, Universidade de São Paulo, Avenida Trabalhador Sãocarlense 400, São Carlos 13566-590, SP, Brazil
| | - Nathalia Gonsales da Rosa Garzon
- Department of Pharmaceutical Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto 14040-903, Brazil
| | - Flávio Antônio de Oliveira Simões
- Department of Pharmaceutical Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto 14040-903, Brazil
| | | | - Igor Polikarpov
- Instituto de Física de São Carlos, Universidade de São Paulo, Avenida Trabalhador Sãocarlense 400, São Carlos 13566-590, SP, Brazil
| | - Hamilton Cabral
- Department of Pharmaceutical Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto 14040-903, Brazil.
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27
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Heparin-Induced Changes of Vascular Endothelial Growth Factor (VEGF 165) Structure. Biomolecules 2023; 13:biom13010098. [PMID: 36671483 PMCID: PMC9856036 DOI: 10.3390/biom13010098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 12/28/2022] [Accepted: 01/01/2023] [Indexed: 01/06/2023] Open
Abstract
Vascular endothelial growth factor-A (VEGF-A), a secreted homodimeric glycoprotein, is a critical regulator of angiogenesis in normal and pathological states. The binding of heparin (HE) to VEGF165 (the major form of VEGF-A) modulates the angiogenesis-related cascade, but the mechanism of the observed changes at the structural level is still insufficiently explored. In the present study, we examined the effect of HE on the structural and physicochemical properties of recombinant human VEGF165 (rhVEGF165). The HE binding results in an increase of hydrophobic surface exposure in rhVEGF165 without changes in its secondary structure. Differential scanning calorimetry measurements for intact and HE-bound rhVEGF165 reveals the absence of any pronounced thermally induced transitions in the protein in the temperature range from 20 to 100 °C. The apolar area increase during the heparin binding explains the pronounced HE-induced oligomerization/aggregation of rhVEGF165, as studied by chemical glutaraldehyde cross-linking and dynamic light scattering. Molecular modeling and docking techniques were used to model the full structure of dimeric VEGF165 and to reveal putative molecular mechanisms underlying the function of the VEGF165/HE system. In general, the results obtained can be a basis for explaining the modulating effect of HE on the biological activity of VEGF-A.
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28
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Ashish. Visualizing how inclusion of higher reciprocal space in SWAXS data analysis improves shape restoration of biomolecules: case of lysozyme. J Biomol Struct Dyn 2022; 40:12975-12989. [PMID: 34569414 DOI: 10.1080/07391102.2021.1977704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Query remains whether use of increased resolution data from X-ray scattering aids in better understanding of the dynamic shape of the biomolecule in solution? To address this, we acquired Small/Wide angle X-ray scattering (SWAXS) data in the q range of 0.008 - 1.72 Å-1 from dilute solutions of lysozyme (0.9 to 5 mg/ml). Samples lacked any interparticulate effect and datasets showed Bragg peaks at q∼0.325, 0.65 and 1.4 Å-1, as reported before by other authors. Considering an averaged profile, we estimated shape parameters and distance distribution profiles of interatomic vectors by gradually increasing input qmax value. Interestingly, use of higher resolution led to emergence of new peaks amongst smaller vectors. Deconvolution of these peaks provided positions of smaller peaks which correlated well with an earlier theoretical work. These peaks arise from secondary structures or due to non-uniform internal motions within the larger shape of this protein. Dummy residue modeling considering uniform density yielded model(s) with holes or cavities when considering higher q values implying limitations of this method. Employing normal mode calculations, we searched for better fitting model of lysozyme using differentially ranged SWAXS data and a crystal structure of lysozyme as starting structure. Comparison of refined models with structures from crystallography and NMR data showed that use of data till mid q region resulted in adjustments near the center of mass of starting structure, and inclusion of higher resolution induced pan-structure adjustments. We conclude that high resolution SWAXS data analysis provides additional dimension towards understanding biomolecular structural dynamics.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Ashish
- CSIR-Institute of Microbial Technology, Chandigarh, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
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29
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Sanchez-Fernandez A, Basic M, Xiang J, Prevost S, Jackson AJ, Dicko C. Hydration in Deep Eutectic Solvents Induces Non-monotonic Changes in the Conformation and Stability of Proteins. J Am Chem Soc 2022; 144:23657-23667. [PMID: 36524921 PMCID: PMC9801427 DOI: 10.1021/jacs.2c11190] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The preservation of labile biomolecules presents a major challenge in chemistry, and deep eutectic solvents (DESs) have emerged as suitable environments for this purpose. However, how the hydration of DESs impacts the behavior of proteins is often neglected. Here, we demonstrate that the amino acid environment and secondary structure of two proteins (bovine serum albumin and lysozyme) and an antibody (immunoglobulin G) in 1:2 choline chloride:glycerol and 1:2 choline chloride:urea follow a re-entrant behavior with solvent hydration. A dome-shaped transition is observed with a folded or partially folded structure at very low (<10 wt % H2O) and high (>40 wt % H2O) DES hydration, while protein unfolding increases between those regimes. Hydration also affects protein conformation and stability, as demonstrated for bovine serum albumin in hydrated 1:2 choline chloride:glycerol. In the neat DES, bovine serum albumin remains partially folded and unexpectedly undergoes unfolding and oligomerization at low water content. At intermediate hydration, the protein begins to refold and gradually retrieves the native monomer-dimer equilibrium. However, ca. 36 wt % H2O is required to recover the native folding fully. The half-denaturation temperature of the protein increases with decreasing hydration, but even the dilute DESs significantly enhance the thermal stability of bovine serum albumin. Also, protein unfolding can be reversed by rehydrating the sample to the high hydration regime, also recovering protein function. This correlation provides a new perspective to understanding protein behavior in hydrated DESs, where quantifying the DES hydration becomes imperative to identifying the folding and stability of proteins.
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Affiliation(s)
- Adrian Sanchez-Fernandez
- Centro
Singular de Investigación en Química Biolóxica
e Materiais Moleculares (CIQUS), Universidade
de Santiago de Compostela, Rúa de Jenaro de la Fuente, s/n, Santiago de Compostela 15705, Spain,Food
Technology, Engineering and Nutrition, Lund
University, Box 124, Lund 221 00, Sweden,
| | - Medina Basic
- Food
Technology, Engineering and Nutrition, Lund
University, Box 124, Lund 221 00, Sweden
| | - Jenny Xiang
- Food
Technology, Engineering and Nutrition, Lund
University, Box 124, Lund 221 00, Sweden
| | - Sylvain Prevost
- Institut
Laue-Langevin, DS / LSS,
71 Avenue des Martyrs, Grenoble 38000, France
| | - Andrew J. Jackson
- European
Spallation Source, Box
176, Lund 221 00, Sweden,Department
of Physical Chemistry, Lund University, Box 124, Lund 221 00, Sweden
| | - Cedric Dicko
- Pure
and
Applied Biochemistry, Department of Chemistry, Lund University, Box
124, Lund SE-221 00, Sweden,Lund
Institute of Advanced Neutron and X-ray Science, SE-223 70 Lund, Sweden
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30
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Wu Z, Jayaraman A. Machine Learning-Enhanced Computational Reverse-Engineering Analysis for Scattering Experiments (CREASE) for Analyzing Fibrillar Structures in Polymer Solutions. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c02165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Zijie Wu
- Department of Chemical and Biomolecular Engineering, University of Delaware, 150 Academy St., Newark, Delaware19716, United States
| | - Arthi Jayaraman
- Department of Chemical and Biomolecular Engineering, University of Delaware, 150 Academy St., Newark, Delaware19716, United States
- Department of Materials Science and Engineering, University of Delaware, 201 DuPont Hall, Newark, Delaware19716, United States
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31
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Bai Y, Jiao W, Vörster J, Parker EJ. Conformational interdomain flexibility in a bacterial α-isopropylmalate synthase is necessary for leucine biosynthesis. J Biol Chem 2022; 299:102789. [PMID: 36509144 PMCID: PMC9860122 DOI: 10.1016/j.jbc.2022.102789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 12/01/2022] [Accepted: 12/05/2022] [Indexed: 12/13/2022] Open
Abstract
α-Isopropylmalate synthase (IPMS) catalyzes the first step in leucine (Leu) biosynthesis and is allosterically regulated by the pathway end product, Leu. IPMS is a dimeric enzyme with each chain consisting of catalytic, accessory, and regulatory domains, with the accessory and regulatory domains of each chain sitting adjacent to the catalytic domain of the other chain. The IPMS crystal structure shows significant asymmetry because of different relative domain conformations in each chain. Owing to the challenges posed by the dynamic and asymmetric structures of IPMS enzymes, the molecular details of their catalytic and allosteric mechanisms are not fully understood. In this study, we have investigated the allosteric feedback mechanism of the IPMS enzyme from the bacterium that causes meningitis, Neisseria meningitidis (NmeIPMS). By combining molecular dynamics simulations with small-angle X-ray scattering, mutagenesis, and heterodimer generation, we demonstrate that Leu-bound NmeIPMS is in a rigid conformational state stabilized by asymmetric interdomain polar interactions. Furthermore, we found removing these polar interactions by mutagenesis impaired the allosteric response without compromising Leu binding. Our results suggest that the allosteric inhibition of NmeIPMS is achieved by restricting the flexibility of the accessory and regulatory domains, demonstrating that significant conformational flexibility is required for catalysis.
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Affiliation(s)
- Yu Bai
- Ferrier Research Institute, Victoria University of Wellington, Wellington, New Zealand,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Wanting Jiao
- Ferrier Research Institute, Victoria University of Wellington, Wellington, New Zealand,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Jan Vörster
- School of Chemical and Physical Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Emily J. Parker
- Ferrier Research Institute, Victoria University of Wellington, Wellington, New Zealand,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand,For correspondence: Emily J. Parker
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32
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Esposito D, Dudley-Fraser J, Garza-Garcia A, Rittinger K. Divergent self-association properties of paralogous proteins TRIM2 and TRIM3 regulate their E3 ligase activity. Nat Commun 2022; 13:7583. [PMID: 36481767 PMCID: PMC9732051 DOI: 10.1038/s41467-022-35300-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 11/25/2022] [Indexed: 12/13/2022] Open
Abstract
Tripartite motif (TRIM) proteins constitute a large family of RING-type E3 ligases that share a conserved domain architecture. TRIM2 and TRIM3 are paralogous class VII TRIM members that are expressed mainly in the brain and regulate different neuronal functions. Here we present a detailed structure-function analysis of TRIM2 and TRIM3, which despite high sequence identity, exhibit markedly different self-association and activity profiles. We show that the isolated RING domain of human TRIM3 is monomeric and inactive, and that this lack of activity is due to a few placental mammal-specific amino acid changes adjacent to the core RING domain that prevent self-association but not E2 recognition. We demonstrate that the activity of human TRIM3 RING can be restored by substitution with the relevant region of human TRIM2 or by hetero-dimerization with human TRIM2, establishing that subtle amino acid changes can profoundly affect TRIM protein activity. Finally, we show that TRIM2 and TRIM3 interact in a cellular context via their filamin and coiled-coil domains, respectively.
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Affiliation(s)
- Diego Esposito
- grid.451388.30000 0004 1795 1830Molecular Structure of Cell Signalling Laboratory, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT UK
| | - Jane Dudley-Fraser
- grid.451388.30000 0004 1795 1830Molecular Structure of Cell Signalling Laboratory, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT UK
| | - Acely Garza-Garcia
- grid.451388.30000 0004 1795 1830Mycobacterial Metabolism and Antibiotic Research Laboratory, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT UK
| | - Katrin Rittinger
- grid.451388.30000 0004 1795 1830Molecular Structure of Cell Signalling Laboratory, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT UK
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33
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Stiegler AL, Vish KJ, Boggon TJ. Tandem engagement of phosphotyrosines by the dual SH2 domains of p120RasGAP. Structure 2022; 30:1603-1614.e5. [PMID: 36417908 PMCID: PMC9722645 DOI: 10.1016/j.str.2022.10.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 09/22/2022] [Accepted: 10/27/2022] [Indexed: 11/23/2022]
Abstract
p120RasGAP is a multidomain GTPase-activating protein for Ras. The presence of two Src homology 2 domains in an SH2-SH3-SH2 module raises the possibility that p120RasGAP simultaneously binds dual phosphotyrosine residues in target proteins. One known binding partner with two proximal phosphotyrosines is p190RhoGAP, a GTPase-activating protein for Rho GTPases. Here, we present the crystal structure of the p120RasGAP SH2-SH3-SH2 module bound to a doubly tyrosine-phosphorylated p190RhoGAP peptide, revealing simultaneous phosphotyrosine recognition by the SH2 domains. The compact arrangement places the SH2 domains in close proximity resembling an SH2 domain tandem and exposed SH3 domain. Affinity measurements support synergistic binding, while solution scattering reveals that dual phosphotyrosine binding induces compaction of this region. Our studies reflect a binding mode that limits conformational flexibility within the SH2-SH3-SH2 cassette and relies on the spacing and sequence surrounding the two phosphotyrosines, potentially representing a selectivity mechanism for downstream signaling events.
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Affiliation(s)
- Amy L Stiegler
- Department of Pharmacology, Yale University, New Haven, CT, USA
| | - Kimberly J Vish
- Department of Pharmacology, Yale University, New Haven, CT, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Titus J Boggon
- Department of Pharmacology, Yale University, New Haven, CT, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA; Yale Cancer Center, Yale University, New Haven, CT, USA.
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34
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Lenton S, Fagerberg E, Tully M, Skepö M. From dilute to concentrated solutions of intrinsically disordered proteins: Interpretation and analysis of collected data. Methods Enzymol 2022; 678:299-330. [PMID: 36641212 DOI: 10.1016/bs.mie.2022.09.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Intrinsically disordered proteins (IDPs) have a broad energy landscape and consequently sample many different conformations in solution. The innate flexibility of IDPs is exploited in their biological function, and in many instances allows a single IDP to regulate a range of processes in vivo. Due to their highly flexible nature, characterizing the structural properties of IDPs is not straightforward. Often solution-based methods such as Nuclear Magnetic Resonance (NMR), Förster Resonance Energy Transfer (FRET), and Small-Angle X-ray Scattering (SAXS) are used. SAXS is indeed a powerful technique to study the structural and conformational properties of IDPs in solution, and from the obtained SAXS spectra, information about the average size, shape, and extent of oligomerization can be determined. In this chapter, we will introduce model-free methods that can be used to interpret SAXS data and introduce methods that can be used to interpret SAXS data beyond analytical models, for example, by using atomistic and different levels of coarse-grained models in combination with molecular dynamics (MD) and Monte Carlo simulations.
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Affiliation(s)
- Samuel Lenton
- Drug Delivery and Biophysics of Biopharmaceuticals, Department of Pharmacy, University of Copenhagen, Copenhagen, Denmark; Division of Theoretical Chemistry, Lund University, Lund, Sweden
| | - Eric Fagerberg
- Division of Theoretical Chemistry, Lund University, Lund, Sweden
| | - Mark Tully
- BioSAXS beamline, BM29, European Synchrotron Radiation Facility, ESRF, Grenoble, France
| | - Marie Skepö
- Division of Theoretical Chemistry, Lund University, Lund, Sweden; LINXS-Institute of Advanced Neutron and X-ray Science, Lund, Sweden.
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35
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Brosey CA, Shen R, Moiani D, Jones DE, Burnett K, Hura GL, Tainer JA. Applying HT-SAXS to chemical ligand screening. Methods Enzymol 2022; 678:331-350. [PMID: 36641213 DOI: 10.1016/bs.mie.2022.09.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Chemical probes are invaluable tools for investigating essential biological processes. Understanding how small-molecule probes engage biomolecular conformations is critical to developing their functional selectivity. High-throughput solution X-ray scattering is well-positioned to profile target-ligand complexes during probe development, bringing conformational insight and selection to traditional ligand binding assays. Access to high-quality synchrotron SAXS datasets and high-throughput data analysis now allows routine academic users to incorporate conformational information into small-molecule development pipelines. Here we describe a general approach for benchmarking and preparing HT-SAXS chemical screens from small fragment libraries. Using the allosteric oxidoreductase Apoptosis-Inducing Factor (AIF) as an exemplary system, we illustrate how HT-SAXS efficiently identifies an allosteric candidate among hits of a microscale thermophoresis ligand screen. We discuss considerations for pursuing HT-SAXS chemical screening with other systems of interest and reflect on advances to extend screening throughput and sensitivity.
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Affiliation(s)
- Chris A Brosey
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States.
| | - Runze Shen
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Davide Moiani
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Darin E Jones
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Kathryn Burnett
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Greg L Hura
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States; Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA, United States
| | - John A Tainer
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States; Department of Cancer Biology, University of Texas MD Anderson Cancer Center, Houston, TX, United States; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States.
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36
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Sun Y, Li X, Chen R, Liu F, Wei S. Recent advances in structural characterization of biomacromolecules in foods via small-angle X-ray scattering. Front Nutr 2022; 9:1039762. [PMID: 36466419 PMCID: PMC9714470 DOI: 10.3389/fnut.2022.1039762] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 11/03/2022] [Indexed: 08/04/2023] Open
Abstract
Small-angle X-ray scattering (SAXS) is a method for examining the solution structure, oligomeric state, conformational changes, and flexibility of biomacromolecules at a scale ranging from a few Angstroms to hundreds of nanometers. Wide time scales ranging from real time (milliseconds) to minutes can be also covered by SAXS. With many advantages, SAXS has been extensively used, it is widely used in the structural characterization of biomacromolecules in food science and technology. However, the application of SAXS in charactering the structure of food biomacromolecules has not been reviewed so far. In the current review, the principle, theoretical calculations and modeling programs are summarized, technical advances in the experimental setups and corresponding applications of in situ capabilities: combination of chromatography, time-resolved, temperature, pressure, flow-through are elaborated. Recent applications of SAXS for monitoring structural properties of biomacromolecules in food including protein, carbohydrate and lipid are also highlighted, and limitations and prospects for developing SAXS based on facility upgraded and artificial intelligence to study the structural properties of biomacromolecules are finally discussed. Future research should focus on extending machine time, simplifying SAXS data treatment, optimizing modeling methods in order to achieve an integrated structural biology based on SAXS as a practical tool for investigating the structure-function relationship of biomacromolecules in food industry.
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Affiliation(s)
- Yang Sun
- College of Vocational and Technical Education, Yunnan Normal University, Kunming, China
| | - Xiujuan Li
- Pharmaceutical Department, The Affiliated Taian City Central Hospital of Qingdao University, Taian, China
| | - Ruixin Chen
- College of Vocational and Technical Education, Yunnan Normal University, Kunming, China
| | - Fei Liu
- College of Vocational and Technical Education, Yunnan Normal University, Kunming, China
| | - Song Wei
- Tumor Precise Intervention and Translational Medicine Laboratory, The Affiliated Taian City Central Hospital of Qingdao University, Taian, China
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37
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Delhommel F, Martínez-Lumbreras S, Sattler M. Combining NMR, SAXS and SANS to characterize the structure and dynamics of protein complexes. Methods Enzymol 2022; 678:263-297. [PMID: 36641211 DOI: 10.1016/bs.mie.2022.09.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Understanding the structure and dynamics of biological macromolecules is essential to decipher the molecular mechanisms that underlie cellular functions. The description of structure and conformational dynamics often requires the integration of complementary techniques. In this review, we highlight the utility of combining nuclear magnetic resonance (NMR) spectroscopy with small angle scattering (SAS) to characterize these challenging biomolecular systems. NMR can assess the structure and conformational dynamics of multidomain proteins, RNAs and biomolecular complexes. It can efficiently provide information on interaction surfaces, long-distance restraints and relative domain orientations at residue-level resolution. Such information can be readily combined with high-resolution structural data available on subcomponents of biomolecular assemblies. Moreover, NMR is a powerful tool to characterize the dynamics of biomolecules on a wide range of timescales, from nanoseconds to seconds. On the other hand, SAS approaches provide global information on the size and shape of biomolecules and on the ensemble of all conformations present in solution. Therefore, NMR and SAS provide complementary data that are uniquely suited to investigate dynamic biomolecular assemblies. Here, we briefly review the type of data that can be obtained by both techniques and describe different approaches that can be used to combine them to characterize biomolecular assemblies. We then provide guidelines on which experiments are best suited depending on the type of system studied, ranging from fully rigid complexes, dynamic structures that interconvert between defined conformations and systems with very high structural heterogeneity.
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Affiliation(s)
- Florent Delhommel
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany; Bavarian NMR Center, Department of Chemistry, Technical University of Munich, Garching, Germany
| | - Santiago Martínez-Lumbreras
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany; Bavarian NMR Center, Department of Chemistry, Technical University of Munich, Garching, Germany
| | - Michael Sattler
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany; Bavarian NMR Center, Department of Chemistry, Technical University of Munich, Garching, Germany.
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38
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Faylo JL, van Eeuwen T, Gupta K, Murakami K, Christianson DW. Transient Prenyltransferase-Cyclase Association in Fusicoccadiene Synthase, an Assembly-Line Terpene Synthase. Biochemistry 2022; 61:2417-2430. [PMID: 36227241 PMCID: PMC9648990 DOI: 10.1021/acs.biochem.2c00509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Fusicoccadiene synthase from the fungus Phomopsis amygdali (PaFS) is an assembly-line terpene synthase that catalyzes the first two steps in the biosynthesis of Fusiccocin A, a diterpene glycoside. The C-terminal prenyltransferase domain of PaFS catalyzes the condensation of one molecule of C5 dimethylallyl diphosphate and three molecules of C5 isopentenyl diphosphate to form C20 geranylgeranyl diphosphate, which then transits to the cyclase domain for cyclization to form fusicoccadiene. Previous structural studies of PaFS using electron microscopy (EM) revealed a central octameric prenyltransferase core with eight cyclase domains tethered in random distal positions through flexible 70-residue linkers. However, proximal prenyltransferase-cyclase configurations could be captured by covalent cross-linking and observed by cryo-EM and mass spectrometry. Here, we use cryo-EM to show that proximally configured prenyltransferase-cyclase complexes are observable even in the absence of covalent cross-linking; moreover, such complexes can involve multiple cyclase domains. A conserved basic patch on the prenyltransferase domain comprises the primary touchpoint with the cyclase domain. These results support a model for transient prenyltransferase-cyclase association in which the cyclase domains of PaFS are in facile equilibrium between proximal associated and random distal positions relative to the central prenyltransferase octamer. The results of biophysical measurements using small-angle X-ray scattering, analytical ultracentrifugation, dynamic light scattering, and size-exclusion chromatography in-line with multi-angle light scattering are consistent with this model. This model accordingly provides a framework for understanding substrate transit between the prenyltransferase and cyclase domains as well as the cooperativity observed for geranylgeranyl diphosphate cyclization.
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Affiliation(s)
- Jacque L. Faylo
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania, 19104-6323, USA
| | - Trevor van Eeuwen
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6073, USA
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6073, USA
| | - Kushol Gupta
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6073, USA
| | - Kenji Murakami
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6073, USA
| | - David W. Christianson
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania, 19104-6323, USA
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39
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Chinnam NB, Syed A, Hura GL, Hammel M, Tainer JA, Tsutakawa SE. Combining small angle X-ray scattering (SAXS) with protein structure predictions to characterize conformations in solution. Methods Enzymol 2022; 678:351-376. [PMID: 36641214 PMCID: PMC10132260 DOI: 10.1016/bs.mie.2022.09.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Accurate protein structure predictions, enabled by recent advances in machine learning algorithms, provide an entry point to probing structural mechanisms and to integrating and querying many types of biochemical and biophysical results. Limitations in such protein structure predictions can be reduced and addressed through comparison to experimental Small Angle X-ray Scattering (SAXS) data that provides protein structural information in solution. SAXS data can not only validate computational predictions, but can improve conformational and assembly prediction to produce atomic models that are consistent with solution data and biologically relevant states. Here, we describe how to obtain protein structure predictions, compare them to experimental SAXS data and improve models to reflect experimental information from SAXS data. Furthermore, we consider the potential for such experimentally-validated protein structure predictions to broadly improve functional annotation in proteins identified in metagenomics and to identify functional clustering on conserved sites despite low sequence homology.
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Affiliation(s)
- Naga Babu Chinnam
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Aleem Syed
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Greg L Hura
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States; Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA, United States
| | - Michal Hammel
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - John A Tainer
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States; Department of Cancer Biology, University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Susan E Tsutakawa
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States.
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40
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Relations between Structure and Zn(II) Binding Affinity Shed Light on the Mechanisms of Rad50 Hook Domain Functioning and Its Phosphorylation. Int J Mol Sci 2022; 23:ijms231911140. [PMID: 36232441 PMCID: PMC9569753 DOI: 10.3390/ijms231911140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 09/17/2022] [Accepted: 09/19/2022] [Indexed: 11/16/2022] Open
Abstract
The metal binding at protein–protein interfaces is still uncharted territory in intermolecular interactions. To date, only a few protein complexes binding Zn(II) in an intermolecular manner have been deeply investigated. The most notable example of such interfaces is located in the highly conserved Rad50 protein, part of the Mre11-Rad50-Nbs1 (MRN) complex, where Zn(II) is required for homodimerization (Zn(Rad50)2). The high stability of Zn(Rad50)2 is conserved not only for the protein derived from the thermophilic archaeon Pyrococcus furiosus (logK12 = 20.95 for 130-amino-acid-long fragment), which was the first one studied, but also for the human paralog studied here (logK12 = 19.52 for a 183-amino-acid-long fragment). As we reported previously, the extremely high stability results from the metal-coupled folding process where particular Rad50 protein fragments play a critical role. The sequence–structure–stability analysis based on human Rad50 presented here separates the individual structural components that increase the stability of the complex, pointing to amino acid residues far away from the Zn(II) binding site as being largely responsible for the complex stabilization. The influence of the individual components is very well reflected by the previously published crystal structure of the human Rad50 zinc hook (PDB: 5GOX). In addition, we hereby report the effect of phosphorylation of the zinc hook domain, which exerts a destabilizing effect on the domain. This study identifies factors governing the stability of metal-mediated protein–protein interactions and illuminates their molecular basis.
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41
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Spiegelman L, Bahn-Suh A, Montaño ET, Zhang L, Hura GL, Patras KA, Kumar A, Tezcan FA, Nizet V, Tsutakawa SE, Ghosh P. Strengthening of enterococcal biofilms by Esp. PLoS Pathog 2022; 18:e1010829. [PMID: 36103556 PMCID: PMC9512215 DOI: 10.1371/journal.ppat.1010829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 09/26/2022] [Accepted: 08/22/2022] [Indexed: 11/25/2022] Open
Abstract
Multidrug-resistant (MDR) Enterococcus faecalis are major causes of hospital-acquired infections. Numerous clinical strains of E. faecalis harbor a large pathogenicity island that encodes enterococcal surface protein (Esp), which is suggested to promote biofilm production and virulence, but this remains controversial. To resolve this issue, we characterized the Esp N-terminal region, the portion implicated in biofilm production. Small angle X-ray scattering indicated that the N-terminal region had a globular head, which consisted of two DEv-Ig domains as visualized by X-ray crystallography, followed by an extended tail. The N-terminal region was not required for biofilm production but instead significantly strengthened biofilms against mechanical or degradative disruption, greatly increasing retention of Enterococcus within biofilms. Biofilm strengthening required low pH, which resulted in Esp unfolding, aggregating, and forming amyloid-like structures. The pH threshold for biofilm strengthening depended on protein stability. A truncated fragment of the first DEv-Ig domain, plausibly generated by a host protease, was the least stable and sufficient to strengthen biofilms at pH ≤ 5.0, while the entire N-terminal region and intact Esp on the enterococcal surface was more stable and required a pH ≤ 4.3. These results suggested a virulence role of Esp in strengthening enterococcal biofilms in acidic abiotic or host environments. The bacterium Enterococcus faecalis is part of the normal microbiome but can also cause serious hospital-acquired infections. Enterococcus strains isolated from hospitals tend to have certain proteins not found in microbiome strains. Such proteins are therefore likely to be important in infection. We sought to understand the function of one such protein, Esp, through biochemical, biophysical, and microbiological techniques. We found that Esp, which is on the bacterial surface, formed amyloid-like fibrils that prevented removal of biofilms. Biofilms are bacterial communities enmeshed within a matrix, and form within the body or on inert objects like catheters. They promote infection by increasing resistance to antibiotics and interfering with clearance by the immune system. We observed that biofilms that lacked Esp could be disrupted much more easily than those that had Esp. We also found that Esp acted only at low pH (i.e., acidic conditions). Exactly how low a pH depended on whether Esp remained on the bacterial surface or was liberated from the surface by a protease, with a human intestinal protease being a likely cause of liberation. In summary, we found that Esp acts at acidic conditions and likely contributes to virulence by preventing the dispersal of biofilms.
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Affiliation(s)
- Lindsey Spiegelman
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California, United States of America
| | - Adrian Bahn-Suh
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California, United States of America
| | - Elizabeth T. Montaño
- Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, University of California, San Diego, La Jolla, California, United States of America
| | - Ling Zhang
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California, United States of America
| | - Greg L. Hura
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - Kathryn A. Patras
- Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, University of California, San Diego, La Jolla, California, United States of America
| | - Amit Kumar
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California, United States of America
| | - F. Akif Tezcan
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California, United States of America
| | - Victor Nizet
- Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, University of California, San Diego, La Jolla, California, United States of America
| | - Susan E. Tsutakawa
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - Partho Ghosh
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California, United States of America
- * E-mail:
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42
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Characterisation of HOIP RBR E3 ligase conformational dynamics using integrative modelling. Sci Rep 2022; 12:15201. [PMID: 36076045 PMCID: PMC9458678 DOI: 10.1038/s41598-022-18890-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 08/22/2022] [Indexed: 11/29/2022] Open
Abstract
Multidomain proteins composed of individual domains connected by flexible linkers pose a challenge for structural studies due to their intrinsic conformational dynamics. Integrated modelling approaches provide a means to characterise protein flexibility by combining experimental measurements with molecular simulations. In this study, we characterise the conformational dynamics of the catalytic RBR domain of the E3 ubiquitin ligase HOIP, which regulates immune and inflammatory signalling pathways. Specifically, we combine small angle X-ray scattering experiments and molecular dynamics simulations to generate weighted conformational ensembles of the HOIP RBR domain using two different approaches based on maximum parsimony and maximum entropy principles. Both methods provide optimised ensembles that are instrumental in rationalising observed differences between SAXS-based solution studies and available crystal structures and highlight the importance of interdomain linker flexibility.
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43
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Aplin C, Milano SK, Zielinski KA, Pollack L, Cerione RA. Evolving Experimental Techniques for Structure-Based Drug Design. J Phys Chem B 2022; 126:6599-6607. [PMID: 36029222 PMCID: PMC10161966 DOI: 10.1021/acs.jpcb.2c04344] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Structure-based drug design (SBDD) is a prominent method in rational drug development and has traditionally benefitted from the atomic models of protein targets obtained using X-ray crystallography at cryogenic temperatures. In this perspective, we highlight recent advances in the development of structural techniques that are capable of probing dynamic information about protein targets. First, we discuss advances in the field of X-ray crystallography including serial room-temperature crystallography as a method for obtaining high-resolution conformational dynamics of protein-inhibitor complexes. Next, we look at cryogenic electron microscopy (cryoEM), another high-resolution technique that has recently been used to study proteins and protein complexes that are too difficult to crystallize. Finally, we present small-angle X-ray scattering (SAXS) as a potential high-throughput screening tool to identify inhibitors that target protein complexes and protein oligomerization.
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Affiliation(s)
- Cody Aplin
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Shawn K Milano
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Kara A Zielinski
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
| | - Lois Pollack
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
| | - Richard A Cerione
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States.,Department of Molecular Medicine, Cornell University, Ithaca, New York 14853, United States
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44
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Structural interpretations of a flexible cold-active AMS8 lipase by combining small-angle X-ray scattering and molecular dynamics simulation (SAXS-MD). Int J Biol Macromol 2022; 220:1095-1103. [PMID: 36029961 DOI: 10.1016/j.ijbiomac.2022.08.145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 07/25/2022] [Accepted: 08/22/2022] [Indexed: 11/22/2022]
Abstract
Determining structure of highly flexible protein with multiple conformations can be challenging. This paper aims to combine molecular dynamics (MD) and small angle X-ray diffraction (SAX) techniques as a solution to overcome issues related to protein conformation in hardly crystallized protein. Based on prior studies, a cold-active lipase AMS8 was simulated in solvents showing stability in its N-terminal and high flexibility in its C-terminal. However, MD in its own algorithm could not explain the basis of macromolecule conformational transitions or changes related to protein through folding. Hence, by combining SAXS with MD, it is possible to understand the structure of flexible AMS8 lipase in natural space. Based on the findings, SAXS ab-initio model of AMS8 lipase was identified as a monomeric protein in which the optimized model of cold-active lipase AMS8 derived from SAXS data was found to be aligned with AMS8 homology model under series of MD timeframe.
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45
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Mielecki M, Ziemniak M, Ozga M, Borowski R, Antosik J, Kaczyńska A, Pająk B. Structure-Activity Relationship of the Dimeric and Oligomeric Forms of a Cytotoxic Biotherapeutic Based on Diphtheria Toxin. Biomolecules 2022; 12:biom12081111. [PMID: 36009005 PMCID: PMC9406121 DOI: 10.3390/biom12081111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/08/2022] [Accepted: 08/09/2022] [Indexed: 11/29/2022] Open
Abstract
Protein aggregation is a well-recognized problem in industrial preparation, including biotherapeutics. These low-energy states constantly compete with a native-like conformation, which is more pronounced in the case of macromolecules of low stability in the solution. A better understanding of the structure and function of such aggregates is generally required for the more rational development of therapeutic proteins, including single-chain fusion cytotoxins to target specific receptors on cancer cells. Here, we identified and purified such particles as side products of the renaturation process of the single-chain fusion cytotoxin, composed of two diphtheria toxin (DT) domains and interleukin 13 (IL-13), and applied various experimental techniques to comprehensively understand their molecular architecture and function. Importantly, we distinguished soluble purified dimeric and fractionated oligomeric particles from aggregates. The oligomers are polydisperse and multimodal, with a distribution favoring lower and even stoichiometries, suggesting they are composed of dimeric building units. Importantly, all these oligomeric particles and the monomer are cystine-dependent as their innate disulfide bonds have structural and functional roles. Their reduction triggers aggregation. Presumably the dimer and lower oligomers represent the metastable state, retaining the native disulfide bond. Although significantly reduced in contrast to the monomer, they preserve some fraction of bioactivity, manifested by their IL-13RA2 receptor affinity and selective cytotoxic potency towards the U-251 glioblastoma cell line. These molecular assemblies probably preserve structural integrity and native-like fold, at least to some extent. As our study demonstrated, the dimeric and oligomeric cytotoxin may be an exciting model protein, introducing a new understanding of its monomeric counterpart’s molecular characteristics.
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46
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Orr CM, Fisher H, Yu X, Chan CHT, Gao Y, Duriez PJ, Booth SG, Elliott I, Inzhelevskaya T, Mockridge I, Penfold CA, Wagner A, Glennie MJ, White AL, Essex JW, Pearson AR, Cragg MS, Tews I. Hinge disulfides in human IgG2 CD40 antibodies modulate receptor signaling by regulation of conformation and flexibility. Sci Immunol 2022; 7:eabm3723. [PMID: 35857577 DOI: 10.1126/sciimmunol.abm3723] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2024]
Abstract
Antibodies protect from infection, underpin successful vaccines and elicit therapeutic responses in otherwise untreatable cancers and autoimmune conditions. The human IgG2 isotype displays a unique capacity to undergo disulfide shuffling in the hinge region, leading to modulation of its ability to drive target receptor signaling (agonism) in a variety of important immune receptors, through hitherto unexplained molecular mechanisms. To address the underlying process and reveal how hinge disulfide orientation affects agonistic activity, we generated a series of cysteine to serine exchange variants in the hinge region of the clinically relevant monoclonal antibody ChiLob7/4, directed against the key immune receptor CD40. We report how agonistic activity varies with disulfide pattern and is afforded by the presence of a disulfide crossover between F(ab) arms in the agonistic forms, independently of epitope, as observed in the determined crystallographic structures. This structural "switch" affects directly on antibody conformation and flexibility. Small-angle x-ray scattering and ensemble modeling demonstrated that the least flexible variants adopt the fewest conformations and evoke the highest levels of receptor agonism. This covalent change may be amenable for broad implementation to modulate receptor signaling in an epitope-independent manner in future therapeutics.
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Affiliation(s)
- Christian M Orr
- University of Southampton, Biological Sciences, Southampton SO17 1BJ, UK
- University of Southampton, Centre for Cancer Immunology, Southampton SO16 6YD, UK
- Hamburg Centre for Ultrafast Imaging CFEL, Hamburg 22761, Germany
- Diamond Light Source, Didcot OX11 0FA, UK
| | - Hayden Fisher
- University of Southampton, Biological Sciences, Southampton SO17 1BJ, UK
- University of Southampton, Centre for Cancer Immunology, Southampton SO16 6YD, UK
| | - Xiaojie Yu
- University of Southampton, Centre for Cancer Immunology, Southampton SO16 6YD, UK
| | - Claude H-T Chan
- University of Southampton, Centre for Cancer Immunology, Southampton SO16 6YD, UK
| | - Yunyun Gao
- Hamburg Centre for Ultrafast Imaging CFEL, Hamburg 22761, Germany
- Institute for Nanostructure and Solid State Physics, Hamburg 22761, Germany
- Max Planck Institute for the Structure and Dynamics of Matter, Hamburg 22761, Germany
| | - Patrick J Duriez
- University of Southampton, Centre for Cancer Immunology, Southampton SO16 6YD, UK
- University of Southampton, CRUK Protein Core Facility, Southampton, SO16 6YD, UK
| | - Steven G Booth
- University of Southampton, Centre for Cancer Immunology, Southampton SO16 6YD, UK
| | - Isabel Elliott
- University of Southampton, Biological Sciences, Southampton SO17 1BJ, UK
- University of Southampton, Centre for Cancer Immunology, Southampton SO16 6YD, UK
- University of Southampton, School of Chemistry, Southampton SO17 1BJ, UK
| | | | - Ian Mockridge
- University of Southampton, Centre for Cancer Immunology, Southampton SO16 6YD, UK
| | - Christine A Penfold
- University of Southampton, Centre for Cancer Immunology, Southampton SO16 6YD, UK
| | | | - Martin J Glennie
- University of Southampton, Centre for Cancer Immunology, Southampton SO16 6YD, UK
| | - Ann L White
- University of Southampton, Centre for Cancer Immunology, Southampton SO16 6YD, UK
- UCB Pharma, Slough SL1 3WE, UK
| | - Jonathan W Essex
- University of Southampton, School of Chemistry, Southampton SO17 1BJ, UK
- University of Southampton, Institute for Life Sciences, Southampton SO17 1BJ, UK
| | - Arwen R Pearson
- Hamburg Centre for Ultrafast Imaging CFEL, Hamburg 22761, Germany
- Institute for Nanostructure and Solid State Physics, Hamburg 22761, Germany
| | - Mark S Cragg
- University of Southampton, Centre for Cancer Immunology, Southampton SO16 6YD, UK
- University of Southampton, Institute for Life Sciences, Southampton SO17 1BJ, UK
| | - Ivo Tews
- University of Southampton, Biological Sciences, Southampton SO17 1BJ, UK
- University of Southampton, Institute for Life Sciences, Southampton SO17 1BJ, UK
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47
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Zheng L, Lu H, Zan B, Li S, Liu H, Liu Z, Huang J, Liu Y, Jiang F, Liu Q, Feng Y, Hong L. Loosely-packed dynamical structures with partially-melted surface being the key for thermophilic argonaute proteins achieving high DNA-cleavage activity. Nucleic Acids Res 2022; 50:7529-7544. [PMID: 35766425 PMCID: PMC9303296 DOI: 10.1093/nar/gkac565] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 05/19/2022] [Accepted: 06/17/2022] [Indexed: 11/21/2022] Open
Abstract
Prokaryotic Argonaute proteins (pAgos) widely participate in hosts to defend against the invasion of nucleic acids. Compared with the CRISPR-Cas system, which requires a specific motif on the target and can only use RNA as guide, pAgos exhibit precise endonuclease activity on any arbitrary target sequence and can use both RNA and DNA as guide, thus rendering great potential for genome editing applications. Hitherto, most in-depth studies on the structure-function relationship of pAgos were conducted on thermophilic ones, functioning at ∼60 to 100°C, whose structures were, however, determined experimentally at much lower temperatures (20–33°C). It remains unclear whether these low-temperature structures can represent the true conformations of the thermophilic pAgos under their physiological conditions. The present work studied three pAgos, PfAgo, TtAgo and CbAgo, whose physiological temperatures differ significantly (95, 75 and 37°C). By conducting thorough experimental and simulation studies, we found that thermophilic pAgos (PfAgo and TtAgo) adopt a loosely-packed structure with a partially-melted surface at the physiological temperatures, largely different from the compact crystalline structures determined at moderate temperatures. In contrast, the mesophilic pAgo (CbAgo) assumes a compact crystalline structure at its optimal function temperature. Such a partially-disrupted structure endows thermophilic pAgos with great flexibility both globally and locally at the catalytic sites, which is crucial for them to achieve high DNA-cleavage activity. To further prove this, we incubated thermophilic pAgos with urea to purposely disrupt their structures, and the resulting cleavage activity was significantly enhanced below the physiological temperature, even at human body temperature. Further testing of many thermophilic Agos present in various thermophilic prokaryotes demonstrated that their structures are generally disrupted under physiological conditions. Therefore, our findings suggest that the highly dynamical structure with a partially-melted surface, distinct from the low-temperature crystalline structure, could be a general strategy assumed by thermophilic pAgos to achieve the high DNA-cleavage activity.
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Affiliation(s)
- Lirong Zheng
- School of Physics and Astronomy, Institute of Natural Sciences, School of Medicine, Shanghai National Center for Applied Mathematics (SJTU center), Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hui Lu
- State Key laboratory for Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Bing Zan
- School of Physics and Astronomy, Institute of Natural Sciences, School of Medicine, Shanghai National Center for Applied Mathematics (SJTU center), Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Song Li
- School of Physics and Astronomy, Institute of Natural Sciences, School of Medicine, Shanghai National Center for Applied Mathematics (SJTU center), Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hao Liu
- School of Physics and Astronomy, Institute of Natural Sciences, School of Medicine, Shanghai National Center for Applied Mathematics (SJTU center), Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Zhuo Liu
- School of Physics and Astronomy, Institute of Natural Sciences, School of Medicine, Shanghai National Center for Applied Mathematics (SJTU center), Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Juan Huang
- State Key laboratory for Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yongjia Liu
- Instrumental Analysis Center, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Fan Jiang
- School of Physics and Astronomy, Institute of Natural Sciences, School of Medicine, Shanghai National Center for Applied Mathematics (SJTU center), Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Qian Liu
- State Key laboratory for Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yan Feng
- State Key laboratory for Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Liang Hong
- School of Physics and Astronomy, Institute of Natural Sciences, School of Medicine, Shanghai National Center for Applied Mathematics (SJTU center), Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, Shanghai 200240, China
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48
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Berger JE, Teixeira SCM, Reed K, Razinkov VI, Sloey CJ, Qi W, Roberts CJ. High-Pressure, Low-Temperature Induced Unfolding and Aggregation of Monoclonal Antibodies: Role of the Fc and Fab Fragments. J Phys Chem B 2022; 126:4431-4441. [PMID: 35675067 DOI: 10.1021/acs.jpcb.1c10528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The effects of high pressure and low temperature on the stability of two different monoclonal antibodies (MAbs) were examined in this work. Fluorescence and small-angle neutron scattering were used to monitor the in situ effects of pressure to infer shifts in tertiary structure and characterize aggregation prone intermediates. Partial unfolding was observed for both MAbs, to different extents, under a range of pressure/temperature conditions. Fourier transform infrared spectroscopy was also used to monitor ex situ changes in secondary structure. Preservation of native secondary structure after incubation at elevated pressures and subzero ° C temperatures was independent of the extent of tertiary unfolding and reversibility. Several combinations of pressure and temperature were also used to discern the respective contributions of the isolated Ab fragments (Fab and Fc) to unfolding and aggregation. The fragments for each antibody showed significantly different partial unfolding profiles and reversibility. There was not a simple correlation between stability of the full MAb and either the Fc or Fab fragment stabilities across all cases, demonstrating a complex relationship to full MAb unfolding and aggregation behavior. That notwithstanding, the combined use of spectroscopic and scattering techniques provides insights into MAb conformational stability and hysteresis in high-pressure, low-temperature environments.
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Affiliation(s)
- Jordan E Berger
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Susana C M Teixeira
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States.,NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Kaelan Reed
- PharmBIO Products, W. L. Gore & Associates, Elkton, Maryland 21921, United States
| | - Vladimir I Razinkov
- Drug Product Technologies, Amgen, Thousand Oaks, California 91320, United States
| | - Christopher J Sloey
- Drug Product Technologies, Amgen, Thousand Oaks, California 91320, United States
| | - Wei Qi
- Drug Product Technologies, Amgen, Thousand Oaks, California 91320, United States
| | - Christopher J Roberts
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
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49
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D'Souza MH, Mrozowich T, Badmalia MD, Geeraert M, Frederickson A, Henrickson A, Demeler B, Wolfinger MT, Patel TR. Biophysical characterisation of human LincRNA-p21 sense and antisense Alu inverted repeats. Nucleic Acids Res 2022; 50:5881-5898. [PMID: 35639511 PMCID: PMC9177966 DOI: 10.1093/nar/gkac414] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 04/26/2022] [Accepted: 05/09/2022] [Indexed: 12/05/2022] Open
Abstract
Human Long Intergenic Noncoding RNA-p21 (LincRNA-p21) is a regulatory noncoding RNA that plays an important role in promoting apoptosis. LincRNA-p21 is also critical in down-regulating many p53 target genes through its interaction with a p53 repressive complex. The interaction between LincRNA-p21 and the repressive complex is likely dependent on the RNA tertiary structure. Previous studies have determined the two-dimensional secondary structures of the sense and antisense human LincRNA-p21 AluSx1 IRs using SHAPE. However, there were no insights into its three-dimensional structure. Therefore, we in vitro transcribed the sense and antisense regions of LincRNA-p21 AluSx1 Inverted Repeats (IRs) and performed analytical ultracentrifugation, size exclusion chromatography, light scattering, and small angle X-ray scattering (SAXS) studies. Based on these studies, we determined low-resolution, three-dimensional structures of sense and antisense LincRNA-p21. By adapting previously known two-dimensional information, we calculated their sense and antisense high-resolution models and determined that they agree with the low-resolution structures determined using SAXS. Thus, our integrated approach provides insights into the structure of LincRNA-p21 Alu IRs. Our study also offers a viable pipeline for combining the secondary structure information with biophysical and computational studies to obtain high-resolution atomistic models for long noncoding RNAs.
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Affiliation(s)
- Michael H D'Souza
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 3M4, Canada
| | - Tyler Mrozowich
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 3M4, Canada
| | - Maulik D Badmalia
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 3M4, Canada
| | - Mitchell Geeraert
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 3M4, Canada
| | - Angela Frederickson
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 3M4, Canada
| | - Amy Henrickson
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 3M4, Canada
| | - Borries Demeler
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 3M4, Canada.,Department of Chemistry and Biochemistry, University of Montana, Missoula, MT 59812, USA.,NorthWest Biophysics Consortium, University of Lethbridge, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 3M4, Canada
| | - Michael T Wolfinger
- Bioinformatics and Computational Biology, Faculty of Computer Science, Währingerstrasse 29, 1090 Vienna, Austria.,Department of Theoretical Chemistry, University of Vienna, Währingerstrasse 17, 1090 Vienna, Austria
| | - Trushar R Patel
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 3M4, Canada.,Department of Microbiology, Immunology and Infectious Disease, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada.,Li Ka Shing Institute of Virology and Discovery Lab, University of Alberta, Edmonton, AB T6G 2E1, Canada
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50
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Integrative structure determination reveals functional global flexibility for an ultra-multimodular arabinanase. Commun Biol 2022; 5:465. [PMID: 35577850 PMCID: PMC9110388 DOI: 10.1038/s42003-022-03054-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 07/15/2021] [Indexed: 11/08/2022] Open
Abstract
AbnA is an extracellular GH43 α-L-arabinanase from Geobacillus stearothermophilus, a key bacterial enzyme in the degradation and utilization of arabinan. We present herein its full-length crystal structure, revealing the only ultra-multimodular architecture and the largest structure to be reported so far within the GH43 family. Additionally, the structure of AbnA appears to contain two domains belonging to new uncharacterized carbohydrate-binding module (CBM) families. Three crystallographic conformational states are determined for AbnA, and this conformational flexibility is thoroughly investigated further using the "integrative structure determination" approach, integrating molecular dynamics, metadynamics, normal mode analysis, small angle X-ray scattering, dynamic light scattering, cross-linking, and kinetic experiments to reveal large functional conformational changes for AbnA, involving up to ~100 Å movement in the relative positions of its domains. The integrative structure determination approach demonstrated here may apply also to the conformational study of other ultra-multimodular proteins of diverse functions and structures.
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