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From seeds to trees: how E2 enzymes grow ubiquitin chains. Biochem Soc Trans 2023; 51:353-362. [PMID: 36645006 PMCID: PMC9987950 DOI: 10.1042/bst20220880] [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: 11/24/2022] [Revised: 01/03/2023] [Accepted: 01/04/2023] [Indexed: 01/17/2023]
Abstract
Modification of proteins by ubiquitin is a highly regulated process that plays a critical role in eukaryotes, from the construction of signalling platforms to the control of cell division. Aberrations in ubiquitin transfer are associated with many diseases, including cancer and neurodegenerative disorders. The ubiquitin machinery generates a rich code on substrate proteins, spanning from single ubiquitin modifications to polyubiquitin chains with diverse linkage types. Central to this process are the E2 enzymes, which often determine the exact nature of the ubiquitin code. The focus of this mini-review is on the molecular details of how E2 enzymes can initiate and grow ubiquitin chains. In particular, recent developments and biochemical breakthroughs that help explain how the degradative E2 enzymes, Ube2s, Ube2k, and Ube2r, generate complex ubiquitin chains with exquisite specificity will be discussed.
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2
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Shukla PK, Sinha D, Leng AM, Bissell JE, Thatipamula S, Ganguly R, Radmall KS, Skalicky JJ, Shrieve DC, Chandrasekharan MB. Mutations of Rad6 E2 ubiquitin-conjugating enzymes at alanine-126 affect ubiquitination activity and decrease enzyme stability. J Biol Chem 2022; 298:102524. [PMID: 36162503 PMCID: PMC9630792 DOI: 10.1016/j.jbc.2022.102524] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 09/16/2022] [Accepted: 09/17/2022] [Indexed: 11/28/2022] Open
Abstract
Rad6, an E2 ubiquitin-conjugating enzyme conserved from yeast to humans, functions in transcription, genome maintenance, and proteostasis. The contributions of many conserved secondary structures of Rad6 and its human homologs UBE2A and UBE2B to their biological functions are not understood. A mutant RAD6 allele with a missense substitution at alanine-126 (A126) of helix-3 that causes defects in telomeric gene silencing, DNA repair, and protein degradation was reported over 2 decades ago. Here, using a combination of genetics, biochemical, biophysical, and computational approaches, we discovered that helix-3 A126 mutations compromise the ability of Rad6 to ubiquitinate target proteins without disrupting interactions with partner E3 ubiquitin-ligases that are required for their various biological functions in vivo. Explaining the defective in vitro or in vivo ubiquitination activities, molecular dynamics simulations and NMR showed that helix-3 A126 mutations cause local disorder of the catalytic pocket of Rad6 in addition to disorganizing the global structure of the protein to decrease its stability in vivo. We also show that helix-3 A126 mutations deform the structures of UBE2A and UBE2B, the human Rad6 homologs, and compromise the in vitro ubiquitination activity and folding of UBE2B. Providing insights into their ubiquitination defects, we determined helix-3 A126 mutations impair the initial ubiquitin charging and the final discharging steps during substrate ubiquitination by Rad6. In summary, our studies reveal that the conserved helix-3 is a crucial structural constituent that controls the organization of catalytic pockets, enzymatic activities, and biological functions of the Rad6-family E2 ubiquitin-conjugating enzymes.
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Affiliation(s)
- Prakash K Shukla
- Department of Radiation Oncology and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Dhiraj Sinha
- IHU, Aix Marseille University, Marseille, France
| | - Andrew M Leng
- Department of Radiation Oncology and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Jesse E Bissell
- Department of Radiation Oncology and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Shravya Thatipamula
- Department of Radiation Oncology and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Rajarshi Ganguly
- Department of Radiation Oncology and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Kaitlin S Radmall
- Department of Radiation Oncology and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Jack J Skalicky
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Dennis C Shrieve
- Department of Radiation Oncology and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Mahesh B Chandrasekharan
- Department of Radiation Oncology and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA.
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3
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Nakasone MA, Majorek KA, Gabrielsen M, Sibbet GJ, Smith BO, Huang DT. Structure of UBE2K-Ub/E3/polyUb reveals mechanisms of K48-linked Ub chain extension. Nat Chem Biol 2022; 18:422-431. [PMID: 35027744 PMCID: PMC8964413 DOI: 10.1038/s41589-021-00952-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 11/30/2021] [Indexed: 01/03/2023]
Abstract
Ubiquitin (Ub) chain types govern distinct biological processes. K48-linked polyUb chains target substrates for proteasomal degradation, but the mechanism of Ub chain synthesis remains elusive due to the transient nature of Ub handover. Here, we present the structure of a chemically trapped complex of the E2 UBE2K covalently linked to donor Ub and acceptor K48-linked di-Ub, primed for K48-linked Ub chain synthesis by a RING E3. The structure reveals the basis for acceptor Ub recognition by UBE2K active site residues and the C-terminal Ub-associated (UBA) domain, to impart K48-linked Ub specificity and catalysis. Furthermore, the structure unveils multiple Ub-binding surfaces on the UBA domain that allow distinct binding modes for K48- and K63-linked Ub chains. This multivalent Ub-binding feature serves to recruit UBE2K to ubiquitinated substrates to overcome weak acceptor Ub affinity and thereby promote chain elongation. These findings elucidate the mechanism of processive K48-linked polyUb chain formation by UBE2K.
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Affiliation(s)
| | | | - Mads Gabrielsen
- Cancer Research UK Beatson Institute, Glasgow, UK
- MVLS Structural Biology and Biophysical Characterisation Facility, University of Glasgow, Glasgow, UK
| | | | - Brian O Smith
- Institute of Molecular Cell and System Biology, University of Glasgow, Glasgow, UK
| | - Danny T Huang
- Cancer Research UK Beatson Institute, Glasgow, UK.
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK.
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Pluska L, Jarosch E, Zauber H, Kniss A, Waltho A, Bagola K, von Delbrück M, Löhr F, Schulman BA, Selbach M, Dötsch V, Sommer T. The UBA domain of conjugating enzyme Ubc1/Ube2K facilitates assembly of K48/K63-branched ubiquitin chains. EMBO J 2021; 40:e106094. [PMID: 33576509 PMCID: PMC7957398 DOI: 10.15252/embj.2020106094] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 12/22/2020] [Accepted: 01/05/2021] [Indexed: 12/23/2022] Open
Abstract
The assembly of a specific polymeric ubiquitin chain on a target protein is a key event in the regulation of numerous cellular processes. Yet, the mechanisms that govern the selective synthesis of particular polyubiquitin signals remain enigmatic. The homologous ubiquitin-conjugating (E2) enzymes Ubc1 (budding yeast) and Ube2K (mammals) exclusively generate polyubiquitin linked through lysine 48 (K48). Uniquely among E2 enzymes, Ubc1 and Ube2K harbor a ubiquitin-binding UBA domain with unknown function. We found that this UBA domain preferentially interacts with ubiquitin chains linked through lysine 63 (K63). Based on structural modeling, in vitro ubiquitination experiments, and NMR studies, we propose that the UBA domain aligns Ubc1 with K63-linked polyubiquitin and facilitates the selective assembly of K48/K63-branched ubiquitin conjugates. Genetic and proteomics experiments link the activity of the UBA domain, and hence the formation of this unusual ubiquitin chain topology, to the maintenance of cellular proteostasis.
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Affiliation(s)
- Lukas Pluska
- Max‐Delbrück‐Center for Molecular Medicine in the Helmholtz AssociationBerlin‐BuchGermany
| | - Ernst Jarosch
- Max‐Delbrück‐Center for Molecular Medicine in the Helmholtz AssociationBerlin‐BuchGermany
| | - Henrik Zauber
- Max‐Delbrück‐Center for Molecular Medicine in the Helmholtz AssociationBerlin‐BuchGermany
| | - Andreas Kniss
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic ResonanceGoethe UniversityFrankfurt am MainGermany
| | - Anita Waltho
- Max‐Delbrück‐Center for Molecular Medicine in the Helmholtz AssociationBerlin‐BuchGermany
| | - Katrin Bagola
- Max‐Delbrück‐Center for Molecular Medicine in the Helmholtz AssociationBerlin‐BuchGermany
| | | | - Frank Löhr
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic ResonanceGoethe UniversityFrankfurt am MainGermany
| | - Brenda A Schulman
- Department of Molecular Machines and SignalingMax Planck Institute of BiochemistryMartinsriedGermany
| | - Matthias Selbach
- Max‐Delbrück‐Center for Molecular Medicine in the Helmholtz AssociationBerlin‐BuchGermany
- Charité – Universitätsmedizin BerlinBerlinGermany
| | - Volker Dötsch
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic ResonanceGoethe UniversityFrankfurt am MainGermany
| | - Thomas Sommer
- Max‐Delbrück‐Center for Molecular Medicine in the Helmholtz AssociationBerlin‐BuchGermany
- Institute for BiologyHumboldt‐Universität zu BerlinBerlinGermany
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5
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Wang Q, Dong Z, Su J, Huang J, Xiao P, Tian L, Chen Y, Ma L, Chen X. Ixazomib inhibits myeloma cell proliferation by targeting UBE2K. Biochem Biophys Res Commun 2021; 549:1-7. [PMID: 33647537 DOI: 10.1016/j.bbrc.2021.02.048] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 02/11/2021] [Indexed: 11/26/2022]
Abstract
PURPOSE Ixazomib is a selective, effective, and reversible inhibitor of 20S proteasome and is approved for the treatment of multiple myeloma. Ubiquitin-conjugating enzyme E2 (UBE2K) is involved in the synthesis of K48-linked ubiquitin chains and is the target of certain drugs used for the treatment of tumors. The purpose of this study was to investigate the relationship between ixazomib and UBE2K in myeloma cells. METHODS We used CCK-8 and Annexin V-FITC/propidium iodide kit to detect the effects of ixazomib on survival and apoptosis of RPMI-8226 and U-266 myeloma cell lines. Quantitative polymerase chain reaction and western blot were used to detect the change in gene and protein expression levels of myeloma cells treated with ixazomib. Furthermore, the regulatory effects of ixazomib on UBE2K and its downstream targets were investigated following the overexpression of UBE2K. RESULTS In myeloma cells, ixazomib decreased cell survival and increased apoptosis in a dose-dependent manner. Ixazomib significantly increased the expression of HIST1H2BD, MNAT1, NEK3, and TARS2, while decreasing the expression of HSPA1B and UBE2K. In addition, ixazomib inhibited the proliferation of myeloma cells, blocked cell cycle, induced cell apoptosis, and increased the production of reactive oxygen species by inhibiting UBE2K expression. Lastly, ixazomib regulates mitosis- and apoptosis-related genes by lowering UBE2K expression. CONCLUSION In summary, ixazomib leads to impaired proliferation of myeloma cells by targeting UBE2K.
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Affiliation(s)
- Qingqing Wang
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Zhigao Dong
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Junnan Su
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Jinmei Huang
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Pingping Xiao
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Lihong Tian
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Yongquan Chen
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Lili Ma
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Xuyan Chen
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
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The Role of Conformational Dynamics in the Recognition and Regulation of Ubiquitination. Molecules 2020; 25:molecules25245933. [PMID: 33333809 PMCID: PMC7765195 DOI: 10.3390/molecules25245933] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 12/07/2020] [Accepted: 12/09/2020] [Indexed: 11/23/2022] Open
Abstract
The ubiquitination pathway is central to many cell signaling and regulatory events. One of the intriguing aspects of the pathway is the combinatorial sophistication of substrate recognition and ubiquitin chain building determinations. The abundant structural and biological data portray several characteristic protein folds among E2 and E3 proteins, and the understanding of the combinatorial complexity that enables interaction with much of the human proteome is a major goal to developing targeted and selective manipulation of the pathway. With the commonality of some folds, there are likely other aspects that can provide differentiation and recognition. These aspects involve allosteric effects and conformational dynamics that can direct recognition and chain building processes. In this review, we will describe the current state of the knowledge for conformational dynamics across a wide timescale, address the limitations of present approaches, and illustrate the potential to make new advances in connecting dynamics with ubiquitination regulation.
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Lambrughi M, Sanader Maršić Ž, Saez-Jimenez V, Mapelli V, Olsson L, Papaleo E. Conformational gating in ammonia lyases. Biochim Biophys Acta Gen Subj 2020; 1864:129605. [PMID: 32222547 DOI: 10.1016/j.bbagen.2020.129605] [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: 09/09/2019] [Revised: 03/11/2020] [Accepted: 03/23/2020] [Indexed: 11/17/2022]
Abstract
BACKGROUND Ammonia lyases are enzymes of industrial and biomedical interest. Knowledge of structure-dynamics-function relationship in ammonia lyases is instrumental for exploiting the potential of these enzymes in industrial or biomedical applications. METHODS We investigated the conformational changes in the proximity of the catalytic pocket of a 3-methylaspartate ammonia lyase (MAL) as a model system. At this scope, we used microsecond all-atom molecular dynamics simulations, analyzed with dimensionality reduction techniques, as well as in terms of contact networks and correlated motions. RESULTS We identify two regulatory elements in the MAL structure, i.e., the β5-α2 loop and the helix-hairpin-loop subdomain. These regulatory elements undergo conformational changes switching from 'occluded' to 'open' states. The rearrangements are coupled to changes in the accessibility of the active site. The β5-α2 loop and the helix-hairpin-loop subdomain modulate the formation of tunnels from the protein surface to the catalytic site, making the active site more accessible to the substrate when they are in an open state. CONCLUSIONS Our work pinpoints a sequential mechanism, in which the helix-hairpin-loop subdomain of MAL needs to break a subset of intramolecular interactions first to favor the displacement of the β5-α2 loop. The coupled conformational changes of these two elements contribute to modulate the accessibility of the catalytic site. GENERAL SIGNIFICANCE Similar molecular mechanisms can have broad relevance in other ammonia lyases with similar regulatory loops. Our results also imply that it is important to account for protein dynamics in the design of variants of ammonia lyases for industrial and biomedical applications.
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Affiliation(s)
- Matteo Lambrughi
- Computational Biology Laboratory, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Željka Sanader Maršić
- Computational Biology Laboratory, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Veronica Saez-Jimenez
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Göteborg, Sweden
| | - Valeria Mapelli
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Göteborg, Sweden
| | - Lisbeth Olsson
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Göteborg, Sweden
| | - Elena Papaleo
- Computational Biology Laboratory, Danish Cancer Society Research Center, Copenhagen, Denmark; Translational Disease Systems Biology, Faculty of Health and Medical Sciences, Novo Nordisk Foundation Center for Protein Research University of Copenhagen, Copenhagen, Denmark.
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8
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Cook BW, Lacoursiere RE, Shaw GS. Recruitment of Ubiquitin within an E2 Chain Elongation Complex. Biophys J 2020; 118:1679-1689. [PMID: 32101714 DOI: 10.1016/j.bpj.2020.02.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 02/06/2020] [Accepted: 02/11/2020] [Indexed: 12/26/2022] Open
Abstract
The ubiquitin (Ub) proteolysis pathway uses an E1, E2, and E3 enzyme cascade to label substrate proteins with ubiquitin and target them for degradation. The mechanisms of ubiquitin chain formation remain unclear and include a sequential addition model, in which polyubiquitin chains are built unit by unit on the substrate, or a preassembly model, in which polyubiquitin chains are preformed on the E2 or E3 enzyme and then transferred in one step to the substrate. The E2 conjugating enzyme UBE2K has a 150-residue catalytic core domain and a C-terminal ubiquitin-associated (UBA) domain. Polyubiquitin chains anchored to the catalytic cysteine and free in solution are formed by UBE2K supporting a preassembly model. To study how UBE2K might assemble polyubiquitin chains, we synthesized UBE2K-Ub and UBE2K-Ub2 covalent complexes and analyzed E2 interactions with the covalently attached Ub and Ub2 moieties using NMR spectroscopy. The UBE2K-Ub complex exists in multiple conformations, including the catalytically competent closed state independent of the UBA domain. In contrast, the UBE2K-Ub2 complex takes on a more extended conformation directed by interactions between the classic I44 hydrophobic face of the distal Ub and the conserved MGF hydrophobic patch of the UBA domain. Our results indicate there are distinct differences between the UBE2K-Ub and UBE2K-Ub2 complexes and show how the UBA domain can alter the position of a polyubiquitin chain attached to the UBE2K active site. These observations provide structural insights into the unique Ub chain-building capacity for UBE2K.
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Affiliation(s)
- Benjamin W Cook
- Department of Biochemistry, The University of Western Ontario, London, Ontario, Canada
| | - Rachel E Lacoursiere
- Department of Biochemistry, The University of Western Ontario, London, Ontario, Canada
| | - Gary S Shaw
- Department of Biochemistry, The University of Western Ontario, London, Ontario, Canada.
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Jones WM, Davis AG, Wilson RH, Elliott KL, Sumner I. A conserved asparagine in a ubiquitin-conjugating enzyme positions the substrate for nucleophilic attack. J Comput Chem 2019; 40:1969-1977. [PMID: 31070815 DOI: 10.1002/jcc.25852] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 02/26/2019] [Accepted: 04/14/2019] [Indexed: 01/30/2023]
Abstract
The mechanism used by the ubiquitin-conjugating enzyme, Ubc13, to catalyze ubiquitination is probed with three computational techniques: Born-Oppenheimer molecular dynamics, single point quantum mechanics/molecular mechanics energies, and classical molecular dynamics. These simulations support a long-held hypothesis and show that Ubc13-catalyzed ubiquitination uses a stepwise, nucleophilic attack mechanism. Furthermore, they show that the first step-the formation of a tetrahedral, zwitterionic intermediate-is rate limiting. However, these simulations contradict another popular hypothesis that supposes that the negative charge on the intermediate is stabilized by a highly conserved asparagine (Asn79 in Ubc13). Instead, calculated reaction profiles of the N79A mutant illustrate how charge stabilization actually increases the barrier to product formation. Finally, an alternate role for Asn79 is suggested by simulations of wild-type, N79A, N79D, and H77A Ubc13: it stabilizes the motion of the electrophile prior to the reaction, positioning it for nucleophilic attack. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Walker M Jones
- Department of Chemistry and Biochemistry, James Madison University, Harrisonburg, Virginia, 22807
| | - Aaron G Davis
- Department of Chemistry and Biochemistry, James Madison University, Harrisonburg, Virginia, 22807
| | - R Hunter Wilson
- Department of Chemistry and Biochemistry, James Madison University, Harrisonburg, Virginia, 22807
| | - Katherine L Elliott
- Department of Chemistry and Biochemistry, James Madison University, Harrisonburg, Virginia, 22807
| | - Isaiah Sumner
- Department of Chemistry and Biochemistry, James Madison University, Harrisonburg, Virginia, 22807
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10
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Alonso-Cotchico L, Rodríguez-Guerra Pedregal J, Lledós A, Maréchal JD. The Effect of Cofactor Binding on the Conformational Plasticity of the Biological Receptors in Artificial Metalloenzymes: The Case Study of LmrR. Front Chem 2019; 7:211. [PMID: 31024897 PMCID: PMC6467942 DOI: 10.3389/fchem.2019.00211] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 03/18/2019] [Indexed: 12/21/2022] Open
Abstract
The design of Artificial Metalloenzymes (ArMs), which result from the incorporation of organometallic cofactors into biological structures, has grown steadily in the last two decades and important new-to-Nature reactions have been reached. These type of exercises could greatly benefit from an understanding of the structural impact that the inclusion of organometallic moieties may have on the biological host. To date though, our understanding of this phenomenon is highly partial. This lack of knowledge is one of the elements that condition that first-generation ArMs generally display relatively poor catalytic profiles. In this work, we approach this matter by assessing the dynamics and stability of a series of ArMs resulting from the inclusion, via different anchoring strategies, of a variety of organometallic cofactors into the Lactococcal multidrug resistance regulator (LmrR) protein. To this aim, we coupled standard force field-based techniques such as Protein-Ligand Docking and Molecular Dynamics simulations with a variety of trajectory convergence analyses, capable of assessing both the stability and flexibility of the different systems under study upon the binding of cofactors. Together with the experimental evidence obtained in other studies, we provide an overview on how these changes can affect the catalytic outcomes obtained from the different ArMs. Fundamentally, our results show that the convergence analysis used in this work can assess how the inclusion of synthetic metallic cofactors in proteins can condition different structural modulations of their host. Those conformational modifications are key to the success of the desired catalytic activity and their proper identification can be wisely used to improve the quality and the rate of success of the ArMs.
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Affiliation(s)
- Lur Alonso-Cotchico
- Departament de Química, Universitat Autònoma de Barcelona, Barcelona, Spain.,Stratingh Institute for Chemistry, University of Groningen, Groningen, Netherlands
| | | | - Agustí Lledós
- Departament de Química, Universitat Autònoma de Barcelona, Barcelona, Spain
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11
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Lee JG, Youn HS, Kang JY, Park SY, Kidera A, Yoo YJ, Eom SH. Crystal structure of the Ube2K/E2-25K and K48-linked di-ubiquitin complex provides structural insight into the mechanism of K48-specific ubiquitin chain synthesis. Biochem Biophys Res Commun 2018; 506:102-107. [DOI: 10.1016/j.bbrc.2018.10.067] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 10/10/2018] [Indexed: 02/08/2023]
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