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Palaniappan C, Rajendran S, Sekar K. Alternate conformations found in protein structures implies biological functions: A case study using cyclophilin A. Curr Res Struct Biol 2024; 7:100145. [PMID: 38690327 PMCID: PMC11059445 DOI: 10.1016/j.crstbi.2024.100145] [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: 09/23/2023] [Revised: 03/16/2024] [Accepted: 04/15/2024] [Indexed: 05/02/2024] Open
Abstract
Protein dynamics linked to numerous biomolecular functions, such as ligand binding, allosteric regulation, and catalysis, must be better understood at the atomic level. Reactive atoms of key residues drive a repertoire of biomolecular functions by flipping between alternate conformations or conformational substates, seldom found in protein structures. Probing such sparsely sampled alternate conformations would provide mechanistic insight into many biological functions. We are therefore interested in evaluating the instance of amino acids adopted alternate conformations, either in backbone or side-chain atoms or in both. Accordingly, over 70000 protein structures appear to contain alternate conformations only 'A' and 'B' for any atom, particularly the instance of amino acids that adopted alternate conformations are more for Arg, Cys, Met, and Ser than others. The resulting protein structure analysis depicts that amino acids with alternate conformations are mainly found in the helical and β-regions and are often seen in high-resolution X-ray crystal structures. Furthermore, a case study on human cyclophilin A (CypA) was performed to explain the pre-existing intrinsic dynamics of catalytically critical residues from the CypA and how such intrinsic dynamics perturbed upon Ser99Thr mutation using molecular dynamics simulations on the ns-μs timescale. Simulation results demonstrated that the Ser99Thr mutation had impaired the alternate conformations or the catalytically productive micro-environment of Phe113, mimicking the experimentally observed perturbation captured by X-ray crystallography. In brief, a deeper comprehension of alternate conformations adopted by the amino acids may shed light on the interplay between protein structure, dynamics, and function.
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Affiliation(s)
- Chandrasekaran Palaniappan
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, 560012, India
- Department of Computational and Data Sciences, Indian Institute of Science, Bangalore, 560012, India
| | - Santhosh Rajendran
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, 560012, India
- Department of Computational and Data Sciences, Indian Institute of Science, Bangalore, 560012, India
| | - Kanagaraj Sekar
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, 560012, India
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2
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Yao XQ, Hamelberg D. Dissecting the Allosteric Fine-Tuning of Enzyme Catalysis. JACS AU 2024; 4:837-846. [PMID: 38425926 PMCID: PMC10900222 DOI: 10.1021/jacsau.3c00806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 01/19/2024] [Accepted: 01/22/2024] [Indexed: 03/02/2024]
Abstract
Fully understanding the mechanism of allosteric regulation in biomolecules requires separating and examining all of the involved factors. In enzyme catalysis, allosteric effector binding shifts the structure and dynamics of the active site, leading to modified energetic (e.g., energy barrier) and dynamical (e.g., diffusion coefficient) factors underlying the catalyzed reaction rate. Such modifications can be subtle and dependent on the type of allosteric effector, representing a fine-tuning of protein function. The microscopic description of allosteric regulation at the level of function-dictating factors has prospective applications in fundamental and pharmaceutical sciences, which is, however, largely missing so far. Here, we characterize the allosteric fine-tuning of enzyme catalysis, using human Pin1 as an example, by performing more than half-millisecond all-atom molecular dynamics simulations. Changes of reaction kinetics and the dictating factors, including the free energy surface along the reaction coordinate and the diffusion coefficient of the reaction dynamics, under various enzyme and allosteric effector binding conditions are examined. Our results suggest equal importance of the energetic and dynamical factors, both of which can be modulated allosterically, and the combined effect determines the final allosteric output. We also reveal the potential dynamic basis for allosteric modulation using an advanced statistical technique to detect function-related conformational dynamics. Methods developed in this work can be applied to other allosteric systems.
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Affiliation(s)
- Xin-Qiu Yao
- Department
of Chemistry, Georgia State University, Atlanta, Georgia 30302-3965, United
States
- Department
of Chemistry, University of Nebraska Omaha, Omaha, Nebraska 68182-0266, United
States
| | - Donald Hamelberg
- Department
of Chemistry, Georgia State University, Atlanta, Georgia 30302-3965, United
States
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3
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Březina V, Hanyková L, Velychkivska N, Hill JP, Labuta J. NMR lineshape analysis using analytical solutions of multi-state chemical exchange with applications to kinetics of host-guest systems. Sci Rep 2022; 12:17369. [PMID: 36253475 PMCID: PMC9576801 DOI: 10.1038/s41598-022-20136-4] [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: 06/20/2022] [Accepted: 09/08/2022] [Indexed: 01/10/2023] Open
Abstract
Nuclear magnetic resonance (NMR) lineshape analysis is a powerful tool for the study of chemical kinetics. Here we provide techniques for analysis of the relationship between experimentally observed spin kinetics (transitions between different environments [Formula: see text]) and corresponding chemical kinetics (transitions between distinct chemical species; e.g., free host and complexed host molecule). The advantages of using analytical solutions for two-, three- or generally N-state exchange lineshapes (without J-coupling) over the widely used numerical calculation for NMR spectral fitting are presented. Several aspects of exchange kinetics including the generalization of coalescence conditions in two-state exchange, the possibility of multiple processes between two states, and differences between equilibrium and steady-state modes are discussed. 'Reduced equivalent schemes' are introduced for spin kinetics containing fast-exchanging states, effectively reducing the number of exchanging states. The theoretical results have been used to analyze a host-guest system containing an oxoporphyrinogen complexed with camphorsulfonic acid and several other literature examples, including isomerization, protein kinetics, or enzymatic reactions. The theoretical treatment and experimental examples present an expansion of the systematic approach to rigorous analyses of systems with rich chemical kinetics through NMR lineshape analysis.
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Affiliation(s)
- Václav Březina
- grid.21941.3f0000 0001 0789 6880International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 Japan ,grid.4491.80000 0004 1937 116XFaculty of Mathematics and Physics, Charles University, V Holešovičkách 2, 180 00 Prague 8, Czech Republic
| | - Lenka Hanyková
- grid.4491.80000 0004 1937 116XFaculty of Mathematics and Physics, Charles University, V Holešovičkách 2, 180 00 Prague 8, Czech Republic
| | - Nadiia Velychkivska
- grid.21941.3f0000 0001 0789 6880International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 Japan ,grid.418095.10000 0001 1015 3316Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovsky Sq. 2, 162 06 Prague 6, Czech Republic
| | - Jonathan P. Hill
- grid.21941.3f0000 0001 0789 6880International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 Japan
| | - Jan Labuta
- grid.21941.3f0000 0001 0789 6880International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 Japan
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4
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Narayanan V, Bobbili KB, Sivaji N, Jayaprakash NG, Suguna K, Surolia A, Sekhar A. Structure and Carbohydrate Recognition by the Nonmitogenic Lectin Horcolin. Biochemistry 2022; 61:464-478. [PMID: 35225598 DOI: 10.1021/acs.biochem.1c00778] [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
Lectins are sugar-binding proteins that have shown considerable promise as antiviral agents because of their ability to interact with envelope glycoproteins present on the surface of viruses such as HIV-1. However, their therapeutic potential has been compromised by their mitogenicity that stimulates uncontrolled division of T-lymphocytes. Horcolin, a member of the jacalin family of lectins, tightly binds the HIV-1 envelope glycoprotein gp120 and neutralizes HIV-1 particles but is nonmitogenic. In this report, we combine X-ray crystallography and NMR spectroscopy to obtain atomic-resolution insights into the structure of horcolin and the molecular basis for its carbohydrate recognition. Each protomer of the horcolin dimer adopts a canonical β-prism I fold with three Greek key motifs and carries two carbohydrate-binding sites. The carbohydrate molecule binds in a negatively charged pocket and is stabilized by backbone and side chain hydrogen bonds to conserved residues in the ligand-binding loop. NMR titrations reveal a two-site binding mode and equilibrium dissociation constants for the two binding sites determined from two-dimensional (2D) lineshape modeling are 4-fold different. Single-binding-site variants of horcolin confirm the dichotomy in binding sites and suggest that there is allosteric communication between the two sites. An analysis of the horcolin structure shows a network of hydrogen bonds linking the two carbohydrate-binding sites directly and through a secondary binding site, and this coupling between the two sites is expected to assume importance in the interaction of horcolin with high-mannose glycans found on viral envelope glycoproteins.
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Affiliation(s)
- Vaishali Narayanan
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
| | - Kishore Babu Bobbili
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
| | - Nukathoti Sivaji
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
| | - Nisha G Jayaprakash
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
| | - Kaza Suguna
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
| | - Avadhesha Surolia
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
| | - Ashok Sekhar
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
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5
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Pazicky S, Werle ALA, Lei J, Löw C, Weininger U. Impact of distant peptide substrate residues on enzymatic activity of SlyD. Cell Mol Life Sci 2022; 79:138. [PMID: 35184231 PMCID: PMC8858294 DOI: 10.1007/s00018-022-04179-4] [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: 10/29/2021] [Revised: 01/18/2022] [Accepted: 01/28/2022] [Indexed: 11/05/2022]
Abstract
Peptidyl-prolyl isomerases (PPIases) catalyze intrinsically slow and often rate-limiting isomerization of prolyl-peptide bonds in unfolded or partially folded proteins, thereby speeding up the folding process and preventing misfolding. They often possess binding and chaperone domains in addition to the domain carrying the isomerization activity. Although generally, their substrates display no identity in their amino acid sequence upstream and downstream of the proline with 20 possibilities for each residue, PPIases are efficient enzymes. SlyD is a highly efficient PPIase consisting of an isomerase domain and an additional chaperone domain. The binding of peptide substrates to SlyD and its enzymatic activity depend to some extend on the proline-proximal residues, however, the impact of proline-distant residues has not been investigated so far. Here, we introduce a label-free NMR-based method to measure SlyD activity on different peptide substrates and analysed the data in the context of obtained binding affinities and several co-crystal structures. We show that especially charged and aromatic residues up to eight positions downstream and three positions upstream of the proline and outside the canonical region of similar conformations affect the activity and binding, although they rarely display distinct conformations in our crystal structures. We hypothesize that these positions primarily influence the association reaction. In the absence of the chaperone domain the isomerase activity strongly correlates with substrate affinity, whereas additional factors play a role in its presence. The mutual orientation of isomerase and chaperone domains depends on the presence of substrates in both binding sites, implying allosteric regulation of enzymatic activity.
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Laurie K, Holcomb D, Kames J, Komar AA, DiCuccio M, Ibla JC, Kimchi-Sarfaty C. In Silico Evaluation of Cyclophilin Inhibitors as Potential Treatment for SARS-CoV-2. Open Forum Infect Dis 2021; 8:ofab189. [PMID: 34109257 PMCID: PMC8083350 DOI: 10.1093/ofid/ofab189] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 04/10/2021] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND The advent of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) provoked researchers to propose multiple antiviral strategies to improve patients' outcomes. Studies provide evidence that cyclosporine A (CsA) decreases SARS-CoV-2 replication in vitro and decreases mortality rates of coronavirus disease 2019 (COVID-19) patients. CsA binds cyclophilins, which isomerize prolines, affecting viral protein activity. METHODS We investigated the proline composition from various coronavirus proteomes to identify proteins that may critically rely on cyclophilin's peptidyl-proline isomerase activity and found that the nucleocapsid (N) protein significantly depends on cyclophilin A (CyPA). We modeled CyPA and N protein interactions to demonstrate the N protein as a potential indirect therapeutic target of CsA, which we propose may impede coronavirus replication by obstructing nucleocapsid folding. RESULTS Finally, we analyzed the literature and protein-protein interactions, finding evidence that, by inhibiting CyPA, CsA may impact coagulation proteins and hemostasis. CONCLUSIONS Despite CsA's promising antiviral characteristics, the interactions between cyclophilins and coagulation factors emphasize risk stratification for COVID patients with thrombosis dispositions.
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Affiliation(s)
- Kyle Laurie
- Center for Biologics Evaluation and Research, Office of Tissues and Advanced Therapies, Division of Plasma Protein Therapeutics, Food and Drug Administration, Silver Spring, Maryland, USA
| | - David Holcomb
- Center for Biologics Evaluation and Research, Office of Tissues and Advanced Therapies, Division of Plasma Protein Therapeutics, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Jacob Kames
- Center for Biologics Evaluation and Research, Office of Tissues and Advanced Therapies, Division of Plasma Protein Therapeutics, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Anton A Komar
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological and Environmental Sciences, Cleveland State University, Cleveland, Ohio, USA
| | - Michael DiCuccio
- National Center of Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - Juan C Ibla
- Division of Cardiac Anesthesia, Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children’s Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Chava Kimchi-Sarfaty
- Center for Biologics Evaluation and Research, Office of Tissues and Advanced Therapies, Division of Plasma Protein Therapeutics, Food and Drug Administration, Silver Spring, Maryland, USA
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7
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Stadmiller SS, Aguilar JS, Waudby CA, Pielak GJ. Rapid Quantification of Protein-Ligand Binding via 19F NMR Lineshape Analysis. Biophys J 2020; 118:2537-2548. [PMID: 32348722 DOI: 10.1016/j.bpj.2020.03.031] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 03/19/2020] [Indexed: 12/14/2022] Open
Abstract
Fluorine incorporation is ideally suited to many NMR techniques, and incorporation of fluorine into proteins and fragment libraries for drug discovery has become increasingly common. Here, we use one-dimensional 19F NMR lineshape analysis to quantify the kinetics and equilibrium thermodynamics for the binding of a fluorine-labeled Src homology 3 (SH3) protein domain to four proline-rich peptides. SH3 domains are one of the largest and most well-characterized families of protein recognition domains and have a multitude of functions in eukaryotic cell signaling. First, we showe that fluorine incorporation into SH3 causes only minor structural changes to both the free and bound states using amide proton temperature coefficients. We then compare the results from lineshape analysis of one-dimensional 19F spectra to those from two-dimensional 1H-15N heteronuclear single quantum coherence spectra. Their agreement demonstrates that one-dimensional 19F lineshape analysis is a robust, low-cost, and fast alternative to traditional heteronuclear single quantum coherence-based experiments. The data show that binding is diffusion limited and indicate that the transition state is highly similar to the free state. We also measured binding as a function of temperature. At equilibrium, binding is enthalpically driven and arises from a highly positive activation enthalpy for association with small entropic contributions. Our results agree with those from studies using different techniques, providing additional evidence for the utility of 19F NMR lineshape analysis, and we anticipate that this analysis will be an effective tool for rapidly characterizing the energetics of protein interactions.
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Affiliation(s)
| | - Jhoan S Aguilar
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina
| | - Christopher A Waudby
- Department of Structural and Molecular Biology, University College London, London, United Kingdom
| | - Gary J Pielak
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina; Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, North Carolina; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina; Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, North Carolina.
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8
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Wapeesittipan P, Mey ASJS, Walkinshaw MD, Michel J. Allosteric effects in cyclophilin mutants may be explained by changes in nano-microsecond time scale motions. Commun Chem 2019. [DOI: 10.1038/s42004-019-0136-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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9
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Rescue of conformational dynamics in enzyme catalysis by directed evolution. Nat Commun 2018; 9:1314. [PMID: 29615624 PMCID: PMC5883053 DOI: 10.1038/s41467-018-03562-9] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 02/23/2018] [Indexed: 12/29/2022] Open
Abstract
Rational design and directed evolution have proved to be successful approaches to increase catalytic efficiencies of both natural and artificial enzymes. Protein dynamics is recognized as important, but due to the inherent flexibility of biological macromolecules it is often difficult to distinguish which conformational changes are directly related to function. Here, we use directed evolution on an impaired mutant of the proline isomerase CypA and identify two second-shell mutations that partially restore its catalytic activity. We show both kinetically, using NMR spectroscopy, and structurally, by room-temperature X-ray crystallography, how local perturbations propagate through a large allosteric network to facilitate conformational dynamics. The increased catalysis selected for in the evolutionary screen is correlated with an accelerated interconversion between the two catalytically essential conformational sub-states, which are both captured in the high-resolution X-ray ensembles. Our data provide a glimpse of an evolutionary trajectory and show how subtle changes can fine-tune enzyme function.
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10
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Matena A, Rehic E, Hönig D, Kamba B, Bayer P. Structure and function of the human parvulins Pin1 and Par14/17. Biol Chem 2018; 399:101-125. [PMID: 29040060 DOI: 10.1515/hsz-2017-0137] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 09/29/2017] [Indexed: 12/16/2022]
Abstract
Parvulins belong to the family of peptidyl-prolyl cis/trans isomerases (PPIases) assisting in protein folding and in regulating the function of a broad variety of proteins in all branches of life. The human representatives Pin1 and Par14/17 are directly involved in processes influencing cellular maintenance and cell fate decisions such as cell-cycle progression, metabolic pathways and ribosome biogenesis. This review on human parvulins summarizes the current knowledge of these enzymes and intends to oppose the well-studied Pin1 to its less well-examined homolog human Par14/17 with respect to structure, catalytic and cellular function.
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Affiliation(s)
- Anja Matena
- Structural and Medicinal Biochemistry, Center for Medical Biotechnology (ZMB), Faculty of Biology, University of Duisburg-Essen, Universitätsstr. 2, D-45117 Essen, Germany
| | - Edisa Rehic
- Structural and Medicinal Biochemistry, Center for Medical Biotechnology (ZMB), Faculty of Biology, University of Duisburg-Essen, Universitätsstr. 2, D-45117 Essen, Germany
| | - Dana Hönig
- Structural and Medicinal Biochemistry, Center for Medical Biotechnology (ZMB), Faculty of Biology, University of Duisburg-Essen, Universitätsstr. 2, D-45117 Essen, Germany
| | - Bianca Kamba
- Structural and Medicinal Biochemistry, Center for Medical Biotechnology (ZMB), Faculty of Biology, University of Duisburg-Essen, Universitätsstr. 2, D-45117 Essen, Germany
| | - Peter Bayer
- Structural and Medicinal Biochemistry, Center for Medical Biotechnology (ZMB), Faculty of Biology, University of Duisburg-Essen, Universitätsstr. 2, D-45117 Essen, Germany
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11
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Initiation of prolyl cis-trans isomerisation in the CDR-H3 loop of an antibody in response to antigen binding. Sci Rep 2017; 7:16964. [PMID: 29208911 PMCID: PMC5717248 DOI: 10.1038/s41598-017-16766-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 11/16/2017] [Indexed: 01/12/2023] Open
Abstract
Proline cis-trans isomerisation is a regulatory mechanism used in a range of biological processes, and is related to various diseases such as Alzheimers disease and cancer. However, the details of the exact molecular mechanism by which it occurs are not known. Using X-ray crystallography, proline isomerisation has been shown to occur following formation of an antigen-antibody complex between the target epiregulin (EPR) and the antibody 9E5, at proline (Pro103), located in the third complementarity-determining region (CDR) of the heavy chain of 9E5. To obtain an accurate description of the pathway involved in cis-trans isomerisation in this system, we performed ten independent long molecular dynamics (MD) simulations starting at a stable transient bound structure obtained from many short binding MD simulations. As a result, we were able to describe the process by which cis-trans isomerisation is initiated, and suggest a catalysis mechanism for cis-trans isomerization in this antigen-antibody system. We found that Asp102, which is immediately adjacent to Pro103, rotates while changing its interacting partner residues in the light chain of 9E5, and at the same time EPR polar residues help to stabilise the intermediate states in the isomerisation process by interacting strongly with Asp102.
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12
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Vivoli M, Renou J, Chevalier A, Norville IH, Diaz S, Juli C, Atkins H, Holzgrabe U, Renard PY, Sarkar-Tyson M, Harmer NJ. A miniaturized peptidyl-prolyl isomerase enzyme assay. Anal Biochem 2017; 536:59-68. [PMID: 28803887 DOI: 10.1016/j.ab.2017.08.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 08/04/2017] [Accepted: 08/09/2017] [Indexed: 01/15/2023]
Abstract
Prolyl-peptidyl isomerases (PPIases) are enzymes that are found in all living organisms. They form an essential part of the cellular protein folding homeostasis machinery. PPIases are associated with many important human diseases, e.g. cardiovascular disease, cancer and Alzheimer's. The development of novel PPIase inhibitors has been limited by the lack of a rapid, laboratory-based assay for these enzymes, as their substrates and products are challenging to distinguish. A well described continuous assay, coupled with the hydrolysis of a peptide by chymotrypsin is highly effective, but comparatively slow. To address this, we developed an improved version of the traditional assay using a temperature controlled plate reader. This assay allows semi-automated medium throughput assays in an academic laboratory for 84 samples per day. The assay shows lower errors, with an average Z' of 0.72. We further developed the assay using a fluorogenic peptide-based FRET probe. This provides an extremely sensitive PPIase assay using substrate at 200 nM, which approaches single turnover conditions. The fluorescent probe achieves an excellent quenching efficiency of 98.6%, and initial experiments showed acceptable Z' of 0.31 and 0.30 for cyclophilin A and hFKBP12 respectively. The assays provide an improved toolset for the quantitative, biochemical analysis of PPIases.
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Affiliation(s)
- Mirella Vivoli
- College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, United Kingdom
| | - Julien Renou
- Normandie Univ, UNIROUEN, CNRS, INSAREOUEN, COBRA, UMR 6014 & FR 3038, 1 rue Tesnière 76000 Rouen, France
| | - Arnaud Chevalier
- Normandie Univ, UNIROUEN, CNRS, INSAREOUEN, COBRA, UMR 6014 & FR 3038, 1 rue Tesnière 76000 Rouen, France
| | - Isobel H Norville
- Defence Science and Technology Laboratory, Porton Down SP4 0JQ, United Kingdom
| | - Suraya Diaz
- College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, United Kingdom
| | - Christina Juli
- Institute of Pharmacy, University of Würzburg, Am Hubland, 970074 Würzburg, Germany
| | - Helen Atkins
- Defence Science and Technology Laboratory, Porton Down SP4 0JQ, United Kingdom
| | - Ulrike Holzgrabe
- Institute of Pharmacy, University of Würzburg, Am Hubland, 970074 Würzburg, Germany
| | - Pierre-Yves Renard
- Normandie Univ, UNIROUEN, CNRS, INSAREOUEN, COBRA, UMR 6014 & FR 3038, 1 rue Tesnière 76000 Rouen, France
| | - Mitali Sarkar-Tyson
- Defence Science and Technology Laboratory, Porton Down SP4 0JQ, United Kingdom; Marshall Centre for Infectious Diseases, School of Pathology and Laboratory Medicine, University of Western Australia, Crawley, WA 6009, Australia
| | - Nicholas J Harmer
- College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, United Kingdom.
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13
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Wang G, Shen J, Sun J, Jiang Z, Fan J, Wang H, Yu S, Long Y, Liu Y, Bao H, Zhang KX, Han K, Zhu M, Zheng Y, Lin Z, Jiang C, Guo M. Cyclophilin A Maintains Glioma-Initiating Cell Stemness by Regulating Wnt/β-Catenin Signaling. Clin Cancer Res 2017; 23:6640-6649. [PMID: 28790108 DOI: 10.1158/1078-0432.ccr-17-0774] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Revised: 06/02/2017] [Accepted: 08/03/2017] [Indexed: 11/16/2022]
Abstract
Purpose: Glioma-initiating cells (GIC) are glioma stem-like cells that contribute to glioblastoma (GBM) development, recurrence, and resistance to chemotherapy and radiotherapy. They have recently become the focus of novel treatment strategies. Cyclophilin A (CypA) is a cytosolic protein that belongs to the peptidyl-prolyl isomerase (PPIase) family and the major intracellular target of the immunosuppressive drug cyclosporin A (CsA). In this study, we investigate the functions of CypA and its mechanism of action in GICs' development.Experimental Design: We analyzed differences in CypA expression between primary tumors and neurospheres from the GDS database, both before and after GIC differentiation. A series of experiments was conducted to investigate the role of CypA in GIC stemness, self-renewal, proliferation, radiotherapy resistance, and mechanism. We then designed glutathione S-transferase (GST) pulldown and coimmunoprecipitation assays to detect signaling activity.Results: In this study, we demonstrated that CypA promotes GIC stemness, self-renewal, proliferation, and radiotherapy resistance. Mechanistically, we found that CypA binds β-catenin and is recruited to Wnt target gene promoters. By increasing the interaction between β-catenin and TCF4, CypA enhances transcriptional activity.Conclusions: Our results demonstrate that CypA enhances GIC stemness, self-renewal, and radioresistance through Wnt/β-catenin signaling. Due to its promotive effects on GICs, CypA is a potential target for future glioma therapy. Clin Cancer Res; 23(21); 6640-9. ©2017 AACR.
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Affiliation(s)
- Guangzhi Wang
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China.,Department of Medical Service Management, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Jia Shen
- School of Dentistry, University of California, Los Angeles, Los Angeles, California
| | - Jiahang Sun
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Zhenfeng Jiang
- Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Jiabing Fan
- School of Dentistry, University of California, Los Angeles, Los Angeles, California
| | - Hongjun Wang
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Shan Yu
- Department of Pathology, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Yu Long
- Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Yi Liu
- Department of Medical Service Management, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Hongbo Bao
- Department of Neurosurgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, China
| | - Kelvin Xi Zhang
- Department of Biological Chemistry, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, California
| | - Ke Han
- School of Computer and Information Engineering, Harbin University of Commerce, Harbin, Heilongjiang China
| | - Minwei Zhu
- Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Yongri Zheng
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Zhiguo Lin
- Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Chuanlu Jiang
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China.
| | - Mian Guo
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China.
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14
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Shinya S, Ghinet MG, Brzezinski R, Furuita K, Kojima C, Shah S, Kovrigin EL, Fukamizo T. NMR line shape analysis of a multi-state ligand binding mechanism in chitosanase. JOURNAL OF BIOMOLECULAR NMR 2017; 67:309-319. [PMID: 28393280 DOI: 10.1007/s10858-017-0109-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 04/02/2017] [Indexed: 06/07/2023]
Abstract
Chitosan interaction with chitosanase was examined through analysis of spectral line shapes in the NMR HSQC titration experiments. We established that the substrate, chitosan hexamer, binds to the enzyme through the three-state induced-fit mechanism with fast formation of the encounter complex followed by slow isomerization of the bound-state into the final conformation. Mapping of the chemical shift perturbations in two sequential steps of the mechanism highlighted involvement of the substrate-binding subsites and the hinge region in the binding reaction. Equilibrium parameters of the three-state model agreed with the overall thermodynamic dissociation constant determined by ITC. This study presented the first kinetic evidence of the induced-fit mechanism in the glycoside hydrolases.
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Affiliation(s)
- Shoko Shinya
- Department of Advanced Bioscience, Kindai University, 3327-204 Nakamachi, Nara, 631-8505, Japan
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Mariana G Ghinet
- Département de Biologie, Faculté des Sciences, Université de Sherbrooke, 2500, boul. de l'Université, Sherbrooke, QC, J1K 2R1, Canada
- Département de Pharmacologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, J1H 5N4, Canada
| | - Ryszard Brzezinski
- Département de Biologie, Faculté des Sciences, Université de Sherbrooke, 2500, boul. de l'Université, Sherbrooke, QC, J1K 2R1, Canada
| | - Kyoko Furuita
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Chojiro Kojima
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Sneha Shah
- Department of Chemistry, Marquette University, Milwaukee, WI, 53201, USA
| | - Evgenii L Kovrigin
- Department of Chemistry, Marquette University, Milwaukee, WI, 53201, USA.
| | - Tamo Fukamizo
- Department of Advanced Bioscience, Kindai University, 3327-204 Nakamachi, Nara, 631-8505, Japan.
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15
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Holliday MJ, Camilloni C, Armstrong GS, Vendruscolo M, Eisenmesser EZ. Networks of Dynamic Allostery Regulate Enzyme Function. Structure 2017; 25:276-286. [PMID: 28089447 DOI: 10.1016/j.str.2016.12.003] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 10/28/2016] [Accepted: 12/12/2016] [Indexed: 11/16/2022]
Abstract
Many protein systems rely on coupled dynamic networks to allosterically regulate function. However, the broad conformational space sampled by non-coherently dynamic systems has precluded detailed analysis of their communication mechanisms. Here, we have developed a methodology that combines the high sensitivity afforded by nuclear magnetic resonance relaxation techniques and single-site multiple mutations, termed RASSMM, to identify two allosterically coupled dynamic networks within the non-coherently dynamic enzyme cyclophilin A. Using this methodology, we discovered two key hotspot residues, Val6 and Val29, that communicate through these networks, the mutation of which altered active-site dynamics, modulating enzymatic turnover of multiple substrates. Finally, we utilized molecular dynamics simulations to identify the mechanism by which one of these hotspots is coupled to the larger dynamic networks. These studies confirm a link between enzyme dynamics and the catalytic cycle of cyclophilin A and demonstrate how dynamic allostery may be engineered to tune enzyme function.
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Affiliation(s)
- Michael Joseph Holliday
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, 12801 East 17th Avenue, MS 8101, Aurora, CO 80045, USA
| | - Carlo Camilloni
- Department of Chemistry, Institute for Advanced Study, Technische Universität München, 85748 Garching, Germany
| | | | | | - Elan Zohar Eisenmesser
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, 12801 East 17th Avenue, MS 8101, Aurora, CO 80045, USA.
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16
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Weininger U, Modig K, Geitner AJ, Schmidpeter PAM, Koch JR, Akke M. Dynamics of Aromatic Side Chains in the Active Site of FKBP12. Biochemistry 2016; 56:334-343. [DOI: 10.1021/acs.biochem.6b01157] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Ulrich Weininger
- Department
of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, P.O.
Box 124, SE-22100 Lund, Sweden
- Institute
of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, D-06120 Halle (Saale), Germany
| | - Kristofer Modig
- Department
of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, P.O.
Box 124, SE-22100 Lund, Sweden
| | - Anne-Juliane Geitner
- Laboratorium
für Biochemie, Bayreuther Zentrum für Molekulare Biowissenschaften, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - Philipp A. M. Schmidpeter
- Laboratorium
für Biochemie, Bayreuther Zentrum für Molekulare Biowissenschaften, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - Johanna R. Koch
- Laboratorium
für Biochemie, Bayreuther Zentrum für Molekulare Biowissenschaften, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - Mikael Akke
- Department
of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, P.O.
Box 124, SE-22100 Lund, Sweden
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17
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Quistgaard EM, Weininger U, Ural-Blimke Y, Modig K, Nordlund P, Akke M, Löw C. Molecular insights into substrate recognition and catalytic mechanism of the chaperone and FKBP peptidyl-prolyl isomerase SlyD. BMC Biol 2016; 14:82. [PMID: 27664121 PMCID: PMC5034536 DOI: 10.1186/s12915-016-0300-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 08/18/2016] [Indexed: 11/25/2022] Open
Abstract
Background Peptidyl-prolyl isomerases (PPIases) catalyze cis/trans isomerization of peptidyl-prolyl bonds, which is often rate-limiting for protein folding. SlyD is a two-domain enzyme containing both a PPIase FK506-binding protein (FKBP) domain and an insert-in-flap (IF) chaperone domain. To date, the interactions of these domains with unfolded proteins have remained rather obscure, with structural information on binding to the FKBP domain being limited to complexes involving various inhibitor compounds or a chemically modified tetrapeptide. Results We have characterized the binding of 15-residue-long unmodified peptides to SlyD from Thermus thermophilus (TtSlyD) in terms of binding thermodynamics and enzyme kinetics through the use of isothermal titration calorimetry, nuclear magnetic resonance spectroscopy, and site-directed mutagenesis. We show that the affinities and enzymatic activity of TtSlyD towards these peptides are much higher than for the chemically modified tetrapeptides that are typically used for activity measurements on FKBPs. In addition, we present a series of crystal structures of TtSlyD with the inhibitor FK506 bound to the FKBP domain, and with 15-residue-long peptides bound to either one or both domains, which reveals that substrates bind in a highly adaptable fashion to the IF domain through β-strand augmentation, and can bind to the FKBP domain as both types VIa1 and VIb-like cis-proline β-turns. Our results furthermore provide important clues to the catalytic mechanism and support the notion of inter-domain cross talk. Conclusions We found that 15-residue-long unmodified peptides can serve as better substrate mimics for the IF and FKBP domains than chemically modified tetrapeptides. We furthermore show how such peptides are recognized by each of these domains in TtSlyD, and propose a novel general model for the catalytic mechanism of FKBPs that involves C-terminal rotation around the peptidyl-prolyl bond mediated by stabilization of the twisted transition state in the hydrophobic binding site. Electronic supplementary material The online version of this article (doi:10.1186/s12915-016-0300-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Esben M Quistgaard
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Scheeles väg 2, SE-17177, Stockholm, Sweden.,Centre for Structural Systems Biology (CSSB), DESY and European Molecular Biology Laboratory Hamburg, Notkestrasse 85, D-22603, Hamburg, Germany
| | - Ulrich Weininger
- Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, PO Box 124, SE-221 00, Lund, Sweden
| | - Yonca Ural-Blimke
- Centre for Structural Systems Biology (CSSB), DESY and European Molecular Biology Laboratory Hamburg, Notkestrasse 85, D-22603, Hamburg, Germany
| | - Kristofer Modig
- Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, PO Box 124, SE-221 00, Lund, Sweden
| | - Pär Nordlund
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Scheeles väg 2, SE-17177, Stockholm, Sweden.,School of Biological Sciences, Nanyang Technological University, 639798, Singapore, Singapore
| | - Mikael Akke
- Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, PO Box 124, SE-221 00, Lund, Sweden
| | - Christian Löw
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Scheeles väg 2, SE-17177, Stockholm, Sweden. .,Centre for Structural Systems Biology (CSSB), DESY and European Molecular Biology Laboratory Hamburg, Notkestrasse 85, D-22603, Hamburg, Germany.
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18
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Cheng S, Luo M, Ding C, Peng C, Lv Z, Tong R, Xiao H, Xie H, Zhou L, Wu J, Zheng S. Downregulation of Peptidylprolyl isomerase A promotes cell death and enhances doxorubicin-induced apoptosis in hepatocellular carcinoma. Gene 2016; 591:236-244. [PMID: 27397650 DOI: 10.1016/j.gene.2016.07.020] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Revised: 07/04/2016] [Accepted: 07/06/2016] [Indexed: 02/05/2023]
Abstract
Peptidylprolyl isomerase A (PPIA) is a peptidyl-prolyl cis-trans isomerase that is known to play a critical role in the development of many human cancers. However, the precise biological function of PPIA in hepatocellular carcinoma (HCC) remains largely unclear. In this study, lentiviral overexpression vectors and small interfering RNA knockdown methods were employed to investigate the biological effects of PPIA in HCC. PPIA levels in HCC tissues and peritumoral tissues were detected by real-time Polymerase Chain Reaction (RT-PCR), Western blotting, and immunohistochemistry. Our results indicate that PPIA levels were significantly higher in the HCC tissues compared to the matched peritumoral tissues. Moreover, PPIA expression was significantly associated with tumor size in these tissues. Interestingly, serum PPIA (sPPIA) levels were significantly higher in healthy controls compared to the HCC patients. Knockdown or overexpression of PPIA was shown to downregulate and upregulate cell growth, respectively. Moreover, PPIA siRNA knockdown appears to promote doxorubicin-induced apoptosis in HCC cells, altering the expression of downstream apoptotic factors. In summary, our results indicate that PPIA may play a pivotal role in HCC by regulating cell growth and could serve as a novel marker and therapeutic molecular target for HCC patients.
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Affiliation(s)
- Shaobing Cheng
- Department of Hepatobiliary Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China; Key Laboratory of Combined Multi-Organ Transplantation, Ministry of Public Health, Key Laboratory of Organ Transplantation, Zhejiang Province, Hangzhou 310003, China
| | - Mengchao Luo
- Department of Hepatobiliary Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Chaofeng Ding
- Department of Hepatobiliary Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Chuanhui Peng
- Department of Hepatobiliary Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Zhen Lv
- Department of Hepatobiliary Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Rongliang Tong
- Department of Hepatobiliary Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Heng Xiao
- Department of Hepatobiliary Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Haiyang Xie
- Department of Hepatobiliary Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Lin Zhou
- Department of Hepatobiliary Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Jian Wu
- Department of Hepatobiliary Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China.
| | - Shusen Zheng
- Department of Hepatobiliary Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China; Key Laboratory of Combined Multi-Organ Transplantation, Ministry of Public Health, Key Laboratory of Organ Transplantation, Zhejiang Province, Hangzhou 310003, China.
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19
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Molecular Mechanism of Pin1–Tau Recognition and Catalysis. J Mol Biol 2016; 428:1760-75. [DOI: 10.1016/j.jmb.2016.03.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 03/08/2016] [Accepted: 03/10/2016] [Indexed: 02/06/2023]
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20
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Waudby CA, Ramos A, Cabrita LD, Christodoulou J. Two-Dimensional NMR Lineshape Analysis. Sci Rep 2016; 6:24826. [PMID: 27109776 PMCID: PMC4843008 DOI: 10.1038/srep24826] [Citation(s) in RCA: 121] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 03/31/2016] [Indexed: 12/18/2022] Open
Abstract
NMR titration experiments are a rich source of structural, mechanistic, thermodynamic and kinetic information on biomolecular interactions, which can be extracted through the quantitative analysis of resonance lineshapes. However, applications of such analyses are frequently limited by peak overlap inherent to complex biomolecular systems. Moreover, systematic errors may arise due to the analysis of two-dimensional data using theoretical frameworks developed for one-dimensional experiments. Here we introduce a more accurate and convenient method for the analysis of such data, based on the direct quantum mechanical simulation and fitting of entire two-dimensional experiments, which we implement in a new software tool, TITAN (TITration ANalysis). We expect the approach, which we demonstrate for a variety of protein-protein and protein-ligand interactions, to be particularly useful in providing information on multi-step or multi-component interactions.
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Affiliation(s)
- Christopher A Waudby
- Institute of Structural and Molecular Biology, University College London and Birkbeck College, London WC1E 6BT, UK
| | - Andres Ramos
- Institute of Structural and Molecular Biology, University College London and Birkbeck College, London WC1E 6BT, UK
| | - Lisa D Cabrita
- Institute of Structural and Molecular Biology, University College London and Birkbeck College, London WC1E 6BT, UK
| | - John Christodoulou
- Institute of Structural and Molecular Biology, University College London and Birkbeck College, London WC1E 6BT, UK
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21
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Dynamical network of residue-residue contacts reveals coupled allosteric effects in recognition, catalysis, and mutation. Proc Natl Acad Sci U S A 2016; 113:4735-40. [PMID: 27071107 DOI: 10.1073/pnas.1523573113] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Detailed understanding of how conformational dynamics orchestrates function in allosteric regulation of recognition and catalysis remains ambiguous. Here, we simulate CypA using multiple-microsecond-long atomistic molecular dynamics in explicit solvent and carry out NMR experiments. We analyze a large amount of time-dependent multidimensional data with a coarse-grained approach and map key dynamical features within individual macrostates by defining dynamics in terms of residue-residue contacts. The effects of substrate binding are observed to be largely sensed at a location over 15 Å from the active site, implying its importance in allostery. Using NMR experiments, we confirm that a dynamic cluster of residues in this distal region is directly coupled to the active site. Furthermore, the dynamical network of interresidue contacts is found to be coupled and temporally dispersed, ranging over 4 to 5 orders of magnitude. Finally, using network centrality measures we demonstrate the changes in the communication network, connectivity, and influence of CypA residues upon substrate binding, mutation, and during catalysis. We identify key residues that potentially act as a bottleneck in the communication flow through the distinct regions in CypA and, therefore, as targets for future mutational studies. Mapping these dynamical features and the coupling of dynamics to function has crucial ramifications in understanding allosteric regulation in enzymes and proteins, in general.
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22
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Ahuja P, Cantrelle FX, Huvent I, Hanoulle X, Lopez J, Smet C, Wieruszeski JM, Landrieu I, Lippens G. Proline Conformation in a Functional Tau Fragment. J Mol Biol 2015; 428:79-91. [PMID: 26655856 DOI: 10.1016/j.jmb.2015.11.023] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 11/05/2015] [Accepted: 11/24/2015] [Indexed: 12/18/2022]
Abstract
The conformational state of distinct prolines can determine the folding of a protein but equally other biological processes when coupled to a conformation-sensitive secondary reaction. For the neuronal tau protein, the importance of proline conformation is underscored by its interaction with different prolyl cis/trans isomerases. The proline conformation would gain even further importance after phosphorylation of the preceding residue by various proline-directed kinases. A number of molecular diseases including Alzheimer's disease and traumatic brain injury were thereby recently qualified as "cistauosis", as they would imply a cis conformation for the pThr231-Pro232 prolyl bond. We here investigate by NMR spectroscopy the conformation of all prolines in a functional Tau fragment, Tau[208-324]. Although we can detect and identify some minor conformers in the cis form, we show that all prolines are for over 90% in the trans conformation. Phosphorylation by CDK2/CycA3, which notably leads to complete modification of the Thr231 residue, does not change this conclusion. Our data hence disagree with the notion that specific prolyl bonds in tau would adopt preferentially the cis conformation.
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Affiliation(s)
- Puneet Ahuja
- UMR8576 CNRS Lille University, 59658 Villeneuve d'Ascq, France
| | | | - Isabelle Huvent
- UMR8576 CNRS Lille University, 59658 Villeneuve d'Ascq, France
| | - Xavier Hanoulle
- UMR8576 CNRS Lille University, 59658 Villeneuve d'Ascq, France
| | - Juan Lopez
- UMR8576 CNRS Lille University, 59658 Villeneuve d'Ascq, France
| | - Caroline Smet
- UMR8576 CNRS Lille University, 59658 Villeneuve d'Ascq, France
| | | | | | - G Lippens
- UMR8576 CNRS Lille University, 59658 Villeneuve d'Ascq, France.
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23
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Holliday MJ, Armstrong GS, Eisenmesser EZ. Determination of the Full Catalytic Cycle among Multiple Cyclophilin Family Members and Limitations on the Application of CPMG-RD in Reversible Catalytic Systems. Biochemistry 2015; 54:5815-27. [PMID: 26335054 DOI: 10.1021/acs.biochem.5b00746] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Cyclophilins catalyze cis ↔ trans isomerization of peptidyl-prolyl bonds, influencing protein folding along with a breadth of other biological functions such as signal transduction. Here, we have determined the microscopic rate constants defining the full enzymatic cycle for three human cyclophilins and a more distantly related thermophilic bacterial cyclophilin when catalyzing interconversion of a biologically representative peptide substrate. The cyclophilins studied here exhibit variability in on-enzyme interconversion as well as an up to 2-fold range in rates of substrate binding and release. However, among the human cyclophilins, the microscopic rate constants appear to have been tuned to maintain remarkably similar isomerization rates without a concurrent conservation of apparent binding affinities. While the structures and active site compositions of the human cyclophilins studied here are highly conserved, we find that the enzymes exhibit significant variability in microsecond to millisecond time scale mobility, suggesting a role for the inherent conformational fluctuations that exist within the cyclophilin family as being functionally relevant in regulating substrate interactions. We have additionally modeled the relaxation dispersion profile given by the commonly employed Carr-Purcell-Meiboom-Gill relaxation dispersion (CPMG-RD) experiment when applied to a reversible enzymatic system such as cyclophilin isomerization and identified a significant limitation in the applicability of this approach for monitoring on-enzyme turnover. Specifically, we show both computationally and experimentally that the CPMG-RD experiment is sensitive to noncatalyzed substrate binding and release in reversible systems even at saturating substrate concentrations unless the on-enzyme interconversion rate is much faster than the substrate release rate.
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Affiliation(s)
- Michael J Holliday
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver , 12801 East 17th Avenue, Aurora, Colorado 80045, United States
| | - Geoffrey S Armstrong
- Department of Chemistry and Biochemistry, University of Colorado , Boulder, Colorado 80309, United States
| | - Elan Z Eisenmesser
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver , 12801 East 17th Avenue, Aurora, Colorado 80045, United States
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24
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Feng W, Xin Y, Xiao Y, Li W, Sun D. Cyclophilin A Enhances Cell Proliferation and Xenografted Tumor Growth of Early Gastric Cancer. Dig Dis Sci 2015; 60:2700-11. [PMID: 26008617 DOI: 10.1007/s10620-015-3694-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 04/29/2015] [Indexed: 12/09/2022]
Abstract
BACKGROUND Recently Cyclophilin A (CypA) was identified as a candidate target protein in gastric carcinoma. However, the role of CypA in gastric cancer (GC) has not been investigated extensively so far. AIM The purpose of this study was to determine the expression pattern of CypA in human GC, and to explore the effects of suppressed CypA expression on cell proliferation and xenografted tumor growth of gastric cancer. METHODS In the present study, we detected the expression pattern of CypA in human GC by immunohistochemistry analysis. Further, the RNAi method was used to silence CypA, and colony formation assay, growth curves, cell cycle and mouse xenograft were analysed. RESULTS An elevated expression of CypA in GC tissues compared with normal gastric mucosa was observed, especially in TNM stage-I and intestinal type of tumor. CypA was overexpressed in most GC cell lines and endogenous expression of CypA correlated with cell growth phenotypes. Transient suppression of CypA reduced the proliferation of BGC-823 and SGC-7901 GC cell lines. Exogenous CypA promoted the proliferation of NCI-N87 GC cells in a concentration dependent manner. Further study revealed that stable CypA silencing inhibited the proliferation, prevented cell cycle and reduced autophagy of BGC-823 GC cells in vitro through suppressing the ERK1/2 signal pathway. Stable CypA silencing also inhibited the growth of xenografted tumor of BGC-823 GC cell in nude mice. CONCLUSIONS These results indicate a special function mode for CypA of playing more important roles in the early stage of gastric tumorigenesis and suggest CypA as a new molecular target of diagnosis and treatment for GC patients.
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Affiliation(s)
- Wenhua Feng
- Department of Gastrointestinal Tumor Pathology of Cancer Institute and General Surgery Institute, The First Hospital of China Medical University, 155 Nanjing North Street, Heping District, Shenyang, 110001, China,
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25
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Holliday MJ, Camilloni C, Armstrong GS, Isern NG, Zhang F, Vendruscolo M, Eisenmesser EZ. Structure and Dynamics of GeoCyp: A Thermophilic Cyclophilin with a Novel Substrate Binding Mechanism That Functions Efficiently at Low Temperatures. Biochemistry 2015; 54:3207-17. [PMID: 25923019 DOI: 10.1021/acs.biochem.5b00263] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Thermophilic proteins have found extensive use in research and industrial applications because of their high stability and functionality at elevated temperatures while simultaneously providing valuable insight into our understanding of protein folding, stability, dynamics, and function. Cyclophilins, constituting a ubiquitously expressed family of peptidyl-prolyl isomerases with a range of biological functions and disease associations, have been utilized both for conferring stress tolerances and in exploring the link between conformational dynamics and enzymatic function. To date, however, no active thermophilic cyclophilin has been fully biophysically characterized. Here, we determine the structure of a thermophilic cyclophilin (GeoCyp) from Geobacillus kaustophilus, characterize its dynamic motions over several time scales using an array of methodologies that include chemical shift-based methods and relaxation experiments over a range of temperatures, and measure catalytic activity over a range of temperatures to compare its structure, dynamics, and function to those of a mesophilic counterpart, human cyclophilin A (CypA). Unlike those of most thermophile/mesophile pairs, GeoCyp catalysis is not substantially impaired at low temperatures as compared to that of CypA, retaining ~70% of the activity of its mesophilic counterpart. Examination of substrate-bound ensembles reveals a mechanism by which the two cyclophilins may have adapted to their environments through altering dynamic loop motions and a critical residue that acts as a clamp to regulate substrate binding differentially in CypA and GeoCyp. Fast time scale (pico- to nanosecond) dynamics are largely conserved between the two proteins, in accordance with the high degree of structural similarity, although differences do exist in their temperature dependencies. Slower (microsecond) time scale motions are likewise localized to similar regions in the two proteins with some variability in their magnitudes yet do not exhibit significant temperature dependencies in either enzyme.
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Affiliation(s)
- Michael J Holliday
- †Department of Biochemistry and Molecular Genetics, University of Colorado Denver, 12801 East 17th Avenue, Aurora, Colorado 80045, United States
| | - Carlo Camilloni
- ‡Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, U.K
| | - Geoffrey S Armstrong
- §Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, United States
| | - Nancy G Isern
- ∥W. R. Wiley Environmental Molecular Sciences Laboratory, High Field NMR Facility, Richland, Washington 99354, United States
| | - Fengli Zhang
- ⊥National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
| | | | - Elan Z Eisenmesser
- †Department of Biochemistry and Molecular Genetics, University of Colorado Denver, 12801 East 17th Avenue, Aurora, Colorado 80045, United States
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Schmidpeter PAM, Schmid FX. Prolyl isomerization and its catalysis in protein folding and protein function. J Mol Biol 2015; 427:1609-31. [PMID: 25676311 DOI: 10.1016/j.jmb.2015.01.023] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 01/30/2015] [Indexed: 12/20/2022]
Abstract
Prolyl isomerizations are intrinsically slow processes. They determine the rates of many protein folding reactions and control regulatory events in folded proteins. Prolyl isomerases are able to catalyze these isomerizations, and thus, they have the potential to assist protein folding and to modulate protein function. Here, we provide examples for how prolyl isomerizations limit protein folding and are accelerated by prolyl isomerases and how native-state prolyl isomerizations regulate protein functions. The roles of prolines in protein folding and protein function are closely interrelated because both of them depend on the coupling between cis/trans isomerization and conformational changes that can involve extended regions of a protein.
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Affiliation(s)
- Philipp A M Schmidpeter
- Laboratorium für Biochemie und Bayreuther Zentrum für Molekulare Biologie, Universität Bayreuth, 95440 Bayreuth, Germany
| | - Franz X Schmid
- Laboratorium für Biochemie und Bayreuther Zentrum für Molekulare Biologie, Universität Bayreuth, 95440 Bayreuth, Germany.
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Ladani ST, Souffrant MG, Barman A, Hamelberg D. Computational perspective and evaluation of plausible catalytic mechanisms of peptidyl-prolyl cis-trans isomerases. Biochim Biophys Acta Gen Subj 2015; 1850:1994-2004. [PMID: 25585011 DOI: 10.1016/j.bbagen.2014.12.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2014] [Revised: 12/23/2014] [Accepted: 12/29/2014] [Indexed: 01/16/2023]
Abstract
BACKGROUND Peptidyl prolyl cis-trans isomerization of the protein backbone is involved in the regulation of many biological processes. Cis-trans isomerization is notoriously slow and is catalyzed by a family of cis-trans peptidyl prolyl isomerases (PPIases) that have been implicated in many diseases. A general consensus on how these enzymes speed up prolyl isomerization has not been reached after decades of both experimental and computational studies. SCOPE OF REVIEW Computational studies carried out to understand the catalytic mechanism of the prototypical FK506 binding protein 12, Cyclophilin A and peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (Pin1) are reviewed. A summary and an evaluation of the implications of the proposed mechanisms from computational studies are presented. MAJOR CONCLUSIONS The analysis of computational studies and evaluation of the proposed mechanisms provide a general consensus and a better understanding of PPIase catalysis. The speedup of the rate of peptidyl-prolyl isomerization by PPIases can be best described by a catalytic mechanism in which the substrate in transition state configuration is stabilized. The enzymes preferentially bind the transition state configuration of the substrate relative to the cis conformation, which in most cases is bound better than the trans conformation of the substrate. Stabilization of the transition state configuration of the substrate leads to a lower free energy barrier and a faster rate of isomerization when compared to the uncatalyzed isomerization reaction. GENERAL SIGNIFICANCE Fully understanding the catalytic mechanism of PPIases has broad implications for drug design, elucidation of the molecular basis of many diseases, protein engineering, and enzyme catalysis in general. This article is part of a Special Issue entitled Proline-directed Foldases: Cell Signaling Catalysts and Drug Targets.
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Affiliation(s)
- Safieh Tork Ladani
- Department of Chemistry and the Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30302-3965, USA
| | - Michael G Souffrant
- Department of Chemistry and the Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30302-3965, USA
| | - Arghya Barman
- Department of Chemistry and the Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30302-3965, USA
| | - Donald Hamelberg
- Department of Chemistry and the Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30302-3965, USA.
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28
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Tork Ladani S, Hamelberg D. Intricacies of interactions, dynamics and solvent effects in enzyme catalysis: a computational perspective on cyclophilin A. MOLECULAR SIMULATION 2014. [DOI: 10.1080/08927022.2014.919498] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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29
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Vögeli B, Orts J, Strotz D, Chi C, Minges M, Wälti MA, Güntert P, Riek R. Towards a true protein movie: a perspective on the potential impact of the ensemble-based structure determination using exact NOEs. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2014; 241:53-59. [PMID: 24656080 DOI: 10.1016/j.jmr.2013.11.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Revised: 11/15/2013] [Accepted: 11/18/2013] [Indexed: 06/03/2023]
Abstract
Confined by the Boltzmann distribution of the energies of the states, a multitude of structural states are inherent to biomolecules. For a detailed understanding of a protein's function, its entire structural landscape at atomic resolution and insight into the interconversion between all the structural states (i.e. dynamics) are required. Whereas dedicated trickery with NMR relaxation provides aspects of local dynamics, and 3D structure determination by NMR is well established, only recently have several attempts been made to formulate a more comprehensive description of the dynamics and the structural landscape of a protein. Here, a perspective is given on the use of exact NOEs (eNOEs) for the elucidation of structural ensembles of a protein describing the covered conformational space.
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Affiliation(s)
- Beat Vögeli
- Laboratory of Physical Chemistry, ETH Zurich, ETH-Hönggerberg, CH-8093 Zürich, Switzerland.
| | - Julien Orts
- Laboratory of Physical Chemistry, ETH Zurich, ETH-Hönggerberg, CH-8093 Zürich, Switzerland
| | - Dean Strotz
- Laboratory of Physical Chemistry, ETH Zurich, ETH-Hönggerberg, CH-8093 Zürich, Switzerland
| | - Celestine Chi
- Laboratory of Physical Chemistry, ETH Zurich, ETH-Hönggerberg, CH-8093 Zürich, Switzerland
| | - Martina Minges
- Laboratory of Physical Chemistry, ETH Zurich, ETH-Hönggerberg, CH-8093 Zürich, Switzerland
| | - Marielle Aulikki Wälti
- Laboratory of Physical Chemistry, ETH Zurich, ETH-Hönggerberg, CH-8093 Zürich, Switzerland
| | - Peter Güntert
- Institute of Biophysical Chemistry, Center for Biomolecular Magnetic Resonance, and Frankfurt Institute for Advanced Studies, J.W. Goethe-Universität, Max-von-Laue-Str. 9, 60438 Frankfurt am Main, Germany; Graduate School of Science, Tokyo Metropolitan University, Hachioji, 192-0397 Tokyo, Japan
| | - Roland Riek
- Laboratory of Physical Chemistry, ETH Zurich, ETH-Hönggerberg, CH-8093 Zürich, Switzerland.
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30
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Doshi U, Hamelberg D. The dilemma of conformational dynamics in enzyme catalysis: perspectives from theory and experiment. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 805:221-43. [PMID: 24446364 DOI: 10.1007/978-3-319-02970-2_10] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The role of protein dynamics in catalysis is a contemporary issue that has stirred intense debate in the field. This chapter provides a brief overview of the approaches and findings of a wide range of experimental, computational and theoretical studies that have addressed this issue. We summarize the results of our recent atomistic molecular dynamic studies on cis-trans isomerase. Our results help to reconcile the disparate perspectives regarding the complex role of enzyme dynamics in the catalytic step and emphasize the major contribution of transition state stabilization in rate enhancement.
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Affiliation(s)
- Urmi Doshi
- Department of Chemistry and the Center for Biotechnology and Drug Design, Georgia State University, Atlanta, GA, 30302-3965, USA,
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31
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Trivedi DK, Ansari MW, Dutta T, Singh P, Tuteja N. Molecular characterization of cyclophilin A-like protein from Piriformospora indica for its potential role to abiotic stress tolerance in E. coli. BMC Res Notes 2013; 6:555. [PMID: 24365575 PMCID: PMC3878271 DOI: 10.1186/1756-0500-6-555] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 12/19/2013] [Indexed: 11/16/2022] Open
Abstract
Background Cyclophilins (CyP), conserved in all genera, are known to have regulatory responses of various cellular processes including stress tolerance. Interestingly, CyP has a crucial role as peptidyl-prolyl cis–trans isomerases (PPIases). Our earlier in silico based approach resulted into the identification of cyclophilin family from rice, Arabidopsis and yeast. In our recent report, we discovered a new OsCYP-25 from rice. Here, we identified a novel cyclophylin A-like protein (PiCyP) from Piriformospora indica which is responsible for abiotic stress tolerance in E. coli. Results Cyclophylin A-like protein (CyPA) (accession number GQ214003) was selected from cDNA library. The genomic organization CyPA revealed a 1304 bp of CyPA in P. indica genome, showing 10 exons and 9 introns. Further, CyPA was evident in PCR with gDNA and cDNA and Southern blot analysis. The phylogenetic examination of CyPA of P. indica showed that it is closed to human cyclophilin. The uniqueness of PiCyPA protein was apparent in western blot study. Kinetics of purified PiCyPA protein for its PPIas activity was determined via first order rate constant (0.104 s-1) in the presence of 1 μg of PiCyPA, with increasing PiCyPA concentration, in the presence of cyclosporin A (CsA) and the inhibition constant (4.435 nM) of CsA for inhibition of PiCyPA. The differential response of E. coli harbouring pET28a-PiCypA was observed for their different degree of tolerance to different abiotic stresses as compared to empty pET28a vector. Conclusions Overexpression of PiCyPA protein E. coli cells confer enhanced tolerance to wide range of abiotic stresses. Thus, this study provides the significance of PiCypA as a molecular chaperone which advanced cellular stress responses of E. coli cells under adverse conditions, and it, furthermore, confirms the mounting the sustainability of E. coli for exploitation in recombinant proteins production. Additionally, the PiCyPA gene cooperates substantial functions in cellular network of stress tolerance mechanism, essentially required for various developmental stages, and might be a potential paramount candidate for crop improvement and its sustainable production under adverse conditions.
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Affiliation(s)
| | | | | | | | - Narendra Tuteja
- Plant Molecular Biology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi 110 067, India.
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Zoldák G, Geitner AJ, Schmid FX. The Prolyl Isomerase SlyD Is a Highly Efficient Enzyme but Decelerates the Conformational Folding of a Client Protein. J Am Chem Soc 2013; 135:4372-9. [DOI: 10.1021/ja311775a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Gabriel Zoldák
- Laboratorium
für Biochemie und Bayreuther Zentrum
für Molekulare Biowissenschaften, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - Anne-Juliane Geitner
- Laboratorium
für Biochemie und Bayreuther Zentrum
für Molekulare Biowissenschaften, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - Franz X. Schmid
- Laboratorium
für Biochemie und Bayreuther Zentrum
für Molekulare Biowissenschaften, Universität Bayreuth, D-95440 Bayreuth, Germany
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33
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McGowan LC, Hamelberg D. Conformational plasticity of an enzyme during catalysis: intricate coupling between cyclophilin A dynamics and substrate turnover. Biophys J 2013; 104:216-26. [PMID: 23332074 DOI: 10.1016/j.bpj.2012.11.3815] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Revised: 11/25/2012] [Accepted: 11/27/2012] [Indexed: 01/15/2023] Open
Abstract
Enzyme catalysis is central to almost all biochemical processes, speeding up rates of reactions to biological relevant timescales. Enzymes make use of a large ensemble of conformations in recognizing their substrates and stabilizing the transition states, due to the inherent dynamical nature of biomolecules. The exact role of these diverse enzyme conformations and the interplay between enzyme conformational dynamics and catalysis is, according to the literature, not well understood. Here, we use molecular dynamics simulations to study human cyclophilin A (CypA), in order to understand the role of enzyme motions in the catalytic mechanism and recognition. Cyclophilin A is a tractable model system to study using classical simulation methods, because catalysis does not involve bond formation or breakage. We show that the conformational dynamics of active site residues of substrate-bound CypA is inherent in the substrate-free enzyme. CypA interacts with its substrate via conformational selection as the configurations of the substrate changes during catalysis. We also show that, in addition to tight intermolecular hydrophobic interactions between CypA and the substrate, an intricate enzyme-substrate intermolecular hydrogen-bonding network is extremely sensitive to the configuration of the substrate. These enzyme-substrate intermolecular interactions are loosely formed when the substrate is in the reactant and product states and become well formed and reluctant to break when the substrate is in the transition state. Our results clearly suggest coupling among enzyme-substrate intermolecular interactions, the dynamics of the enzyme, and the chemical step. This study provides further insights into the mechanism of peptidyl-prolyl cis/trans isomerases and the general interplay between enzyme conformational dynamics and catalysis.
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Affiliation(s)
- Lauren C McGowan
- Department of Chemistry and the Center for Biotechnology and Drug Design, Georgia State University, Atlanta, Georgia, USA
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34
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Markin CJ, Spyracopoulos L. Accuracy and precision of protein-ligand interaction kinetics determined from chemical shift titrations. JOURNAL OF BIOMOLECULAR NMR 2012; 54:355-376. [PMID: 23086713 DOI: 10.1007/s10858-012-9678-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 10/10/2012] [Indexed: 06/01/2023]
Abstract
NMR-monitored chemical shift titrations for the study of weak protein-ligand interactions represent a rich source of information regarding thermodynamic parameters such as dissociation constants (K ( D )) in the micro- to millimolar range, populations for the free and ligand-bound states, and the kinetics of interconversion between states, which are typically within the fast exchange regime on the NMR timescale. We recently developed two chemical shift titration methods wherein co-variation of the total protein and ligand concentrations gives increased precision for the K ( D ) value of a 1:1 protein-ligand interaction (Markin and Spyracopoulos in J Biomol NMR 53: 125-138, 2012). In this study, we demonstrate that classical line shape analysis applied to a single set of (1)H-(15)N 2D HSQC NMR spectra acquired using precise protein-ligand chemical shift titration methods we developed, produces accurate and precise kinetic parameters such as the off-rate (k ( off )). For experimentally determined kinetics in the fast exchange regime on the NMR timescale, k ( off ) ~ 3,000 s(-1) in this work, the accuracy of classical line shape analysis was determined to be better than 5 % by conducting quantum mechanical NMR simulations of the chemical shift titration methods with the magnetic resonance toolkit GAMMA. Using Monte Carlo simulations, the experimental precision for k ( off ) from line shape analysis of NMR spectra was determined to be 13 %, in agreement with the theoretical precision of 12 % from line shape analysis of the GAMMA simulations in the presence of noise and protein concentration errors. In addition, GAMMA simulations were employed to demonstrate that line shape analysis has the potential to provide reasonably accurate and precise k ( off ) values over a wide range, from 100 to 15,000 s(-1). The validity of line shape analysis for k ( off ) values approaching intermediate exchange (~100 s(-1)), may be facilitated by more accurate K ( D ) measurements from NMR-monitored chemical shift titrations, for which the dependence of K ( D ) on the chemical shift difference (Δω) between free and bound states is extrapolated to Δω = 0. The demonstrated accuracy and precision for k ( off ) will be valuable for the interpretation of biological kinetics in weakly interacting protein-protein networks, where a small change in the magnitude of the underlying kinetics of a given pathway may lead to large changes in the associated downstream signaling cascade.
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Affiliation(s)
- Craig J Markin
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
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35
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De S, Greenwood AI, Rogals MJ, Kovrigin EL, Lu KP, Nicholson LK. Complete thermodynamic and kinetic characterization of the isomer-specific interaction between Pin1-WW domain and the amyloid precursor protein cytoplasmic tail phosphorylated at Thr668. Biochemistry 2012; 51:8583-96. [PMID: 23025283 DOI: 10.1021/bi3008214] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Peptidyl prolyl cis-trans isomerization acts as an effective molecular timer that plays significant roles in biological and pathological processes. Enzymes such as Pin1 catalyze cis-trans isomerization, accelerating the otherwise slow isomerization rate into time scales relevant for cellular signaling. Here we have combined NMR line shape analysis, fluorescence spectroscopy, and isothermal titration calorimetry to determine the kinetic and thermodynamic parameters describing the trans-specific interaction between the binding domain of Pin1 (WW domain) and a key cis-trans molecular switch in the amyloid precursor protein cytoplasmic tail. A three-state model, in which the cis-trans isomerization equilibrium is coupled to the binding equilibrium through the trans isomer, was found to fit the data well. The trans isomer binds the WW domain with ∼22 μM affinity via very fast association (approaching the diffusion limit) and dissociation rates. The common structural and electrostatic characteristics of Pin1 substrates, which contain a phosphorylated serine/threonine-proline motif, suggest that very rapid binding kinetics are a general feature of Pin1 interactions with other substrates. The fast binding kinetics of the WW domain allows rapid response of Pin1 to the dynamic events of phosphorylation and dephosphorylation in the cell that alter the relative populations of diverse Pin1 substrates. Furthermore, our results also highlight the vastly different rates at which slow uncatalyzed cis-trans isomerization and fast isomer-specific binding events occur. These results, along with the experimental methods presented herein, should guide future experiments aimed at the thermodynamic and kinetic characterization of cis-trans molecular switches and isomer-specific interactions involved in various biological processes.
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Affiliation(s)
- Soumya De
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
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36
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Ladani ST, Hamelberg D. Entropic and Surprisingly Small Intramolecular Polarization Effects in the Mechanism of Cyclophilin A. J Phys Chem B 2012; 116:10771-8. [DOI: 10.1021/jp305917c] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Safieh Tork Ladani
- Department of Chemistry and Center
for Biotechnology
and Drug Design, Georgia State University, Atlanta, Georgia 30302-4098, United States
| | - Donald Hamelberg
- Department of Chemistry and Center
for Biotechnology
and Drug Design, Georgia State University, Atlanta, Georgia 30302-4098, United States
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Kovrigin EL. NMR line shapes and multi-state binding equilibria. JOURNAL OF BIOMOLECULAR NMR 2012; 53:257-70. [PMID: 22610542 DOI: 10.1007/s10858-012-9636-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 05/01/2012] [Indexed: 05/21/2023]
Abstract
Biological function of proteins relies on conformational transitions and binding of specific ligands. Protein-ligand interactions are thermodynamically and kinetically coupled to conformational changes in protein structures as conceptualized by the models of pre-existing equilibria and induced fit. NMR spectroscopy is particularly sensitive to complex ligand-binding modes-NMR line-shape analysis can provide for thermodynamic and kinetic constants of ligand-binding equilibria with the site-specific resolution. However, broad use of line shape analysis is hampered by complexity of NMR line shapes in multi-state systems. To facilitate interpretation of such spectral patterns, I computationally explored systems where isomerization or dimerization of a protein (receptor) molecule is coupled to binding of a ligand. Through an extensive analysis of multiple exchange regimes for a family of three-state models, I identified signature features to guide an NMR experimentalist in recognizing specific interaction mechanisms. Results show that distinct multi-state models may produce very similar spectral patterns. I also discussed aggregation of a receptor as a possible source of spurious three-state line shapes and provided specific suggestions for complementary experiments that can ensure reliable mechanistic insight.
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Affiliation(s)
- Evgenii L Kovrigin
- Department of Chemistry, Marquette University, PO Box 1881, Milwaukee, WI 53201, USA.
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38
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39
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Kunz C, Jahreis G, Günther R, Berger S, Fischer G, Hofmann HJ. Influence of lithium cations on prolyl peptide bonds. J Pept Sci 2012; 18:400-4. [DOI: 10.1002/psc.2410] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Revised: 03/05/2012] [Accepted: 03/05/2012] [Indexed: 11/09/2022]
Affiliation(s)
- Claudia Kunz
- Institut für Biochemie, Fakultät für Biowissenschaften, Pharmazie und Psychologie; Universität Leipzig; Brüderstraße 34 D-04103 Leipzig Germany
| | - Günther Jahreis
- Max-Planck-Forschungsstelle für Enzymologie der Proteinfaltung; Weinbergweg 22 D-06120 Halle/Saale Germany
| | - Robert Günther
- Institut für Biochemie, Fakultät für Biowissenschaften, Pharmazie und Psychologie; Universität Leipzig; Brüderstraße 34 D-04103 Leipzig Germany
| | - Stefan Berger
- Institut für Analytische Chemie, Fakultät für Chemie und Mineralogie; Universität Leipzig; Johannisallee 29 D-04103 Leipzig Germany
| | - Gunter Fischer
- Max-Planck-Forschungsstelle für Enzymologie der Proteinfaltung; Weinbergweg 22 D-06120 Halle/Saale Germany
| | - Hans-Jörg Hofmann
- Institut für Biochemie, Fakultät für Biowissenschaften, Pharmazie und Psychologie; Universität Leipzig; Brüderstraße 34 D-04103 Leipzig Germany
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40
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Nellas RB, Glover MM, Hamelberg D, Shen T. High-pressure effect on the dynamics of solvated peptides. J Chem Phys 2012; 136:145103. [DOI: 10.1063/1.3700183] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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41
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Resolving the complex role of enzyme conformational dynamics in catalytic function. Proc Natl Acad Sci U S A 2012; 109:5699-704. [PMID: 22451902 DOI: 10.1073/pnas.1117060109] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Despite growing evidence suggesting the importance of enzyme conformational dynamics (ECD) in catalysis, a consensus on how precisely ECD influences the chemical step and reaction rates is yet to be reached. Here, we characterize ECD in Cyclophilin A, a well-studied peptidyl-prolyl cis-trans isomerase, using normal and accelerated, atomistic molecular dynamics simulations. Kinetics and free energy landscape of the isomerization reaction in solution and enzyme are explored in unconstrained simulations by allowing significantly lower torsional barriers, but in no way compromising the atomistic description of the system or the explicit solvent. We reveal that the reaction dynamics is intricately coupled to enzymatic motions that span multiple timescales and the enzyme modes are selected based on the energy barrier of the chemical step. We show that Kramers' rate theory can be used to present a clear rationale of how ECD affects the reaction dynamics and catalytic rates. The effects of ECD can be incorporated into the effective diffusion coefficient, which we estimate to be about ten times slower in enzyme than in solution. ECD thereby alters the preexponential factor, effectively impeding the rate enhancement. From our analyses, the trend observed for lower torsional barriers can be extrapolated to actual isomerization barriers, allowing successful prediction of the speedup in rates in the presence of CypA, which is in notable agreement with experimental estimates. Our results further reaffirm transition state stabilization as the main effect in enhancing chemical rates and provide a unified view of ECD's role in catalysis from an atomistic perspective.
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Arai M, Ferreon JC, Wright PE. Quantitative analysis of multisite protein-ligand interactions by NMR: binding of intrinsically disordered p53 transactivation subdomains with the TAZ2 domain of CBP. J Am Chem Soc 2012; 134:3792-803. [PMID: 22280219 DOI: 10.1021/ja209936u] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Determination of affinities and binding sites involved in protein-ligand interactions is essential for understanding molecular mechanisms in biological systems. Here we combine singular value decomposition and global analysis of NMR chemical shift perturbations caused by protein-protein interactions to determine the number and location of binding sites on the protein surface and to measure the binding affinities. Using this method we show that the isolated AD1 and AD2 binding motifs, derived from the intrinsically disordered N-terminal transactivation domain of the tumor suppressor p53, both interact with the TAZ2 domain of the transcriptional coactivator CBP at two binding sites. Simulations of titration curves and line shapes show that a primary dissociation constant as small as 1-10 nM can be accurately estimated by NMR titration methods, provided that the primary and secondary binding processes are coupled. Unexpectedly, the site of binding of AD2 on the hydrophobic surface of TAZ2 overlaps with the binding site for AD1, but AD2 binds TAZ2 more tightly. The results highlight the complexity of interactions between intrinsically disordered proteins and their targets. Furthermore, the association rate of AD2 to TAZ2 is estimated to be 1.7 × 10(10) M(-1) s(-1), approaching the diffusion-controlled limit and indicating that intrinsic disorder plus complementary electrostatics can significantly accelerate protein binding interactions.
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Affiliation(s)
- Munehito Arai
- Department of Molecular Biology and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
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Solbak SMØ, Reksten TR, Röder R, Wray V, Horvli O, Raae AJ, Henklein P, Henklein P, Fossen T. HIV-1 p6-Another viral interaction partner to the host cellular protein cyclophilin A. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2012; 1824:667-78. [PMID: 22342556 DOI: 10.1016/j.bbapap.2012.02.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 01/12/2012] [Accepted: 02/01/2012] [Indexed: 11/30/2022]
Abstract
The 52-amino acid human immunodeficiency virus type 1 (HIV-1) p6 protein has previously been recognized as a docking site for several cellular and viral binding factors and is important for the formation of infectious viruses. A particular structural feature of p6 is the notably high relative content of proline residues, located at positions 5, 7, 10, 11, 24, 30, 37 and 49 in the sequence. Proline cis/trans isomerism was detected for all these proline residues to such an extent that more than 40% of all p6 molecules contain at least one proline in a cis conformation. 2D (1)H nuclear magnetic resonance analysis of full-length HIV-1 p6 and p6 peptides established that cyclophilin A (CypA) interacts as a peptidyl-prolyl cis/trans isomerase with all proline residues of p6. Only catalytic amounts of CypA were necessary for the interaction with p6 to occur, strongly suggesting that the observed interaction is highly relevant in vivo. In addition, surface plasmon resonance studies revealed binding of full-length p6 to CypA, and that this binding was significantly stronger than any of its N- or C-terminal peptides. This study demonstrates the first identification of an interaction between HIV-1 p6 and the host cellular protein CypA. The mode of interaction involves both transient enzyme-substrate interactions and a more stable binding. The binding motifs of p6 to Tsg-101, ALIX and Vpr coincide with binding regions and catalytic sites of p6 to CypA, suggesting a potential role of CypA in modulating functional interactions of HIV-1.
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Affiliation(s)
- Sara M Ø Solbak
- Department of Chemistry and Centre of Pharmacy, University of Bergen, Bergen, Norway
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Oligopeptide cyclophilin inhibitors: A reassessment. Eur J Med Chem 2011; 46:5556-61. [DOI: 10.1016/j.ejmech.2011.09.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Revised: 09/12/2011] [Accepted: 09/14/2011] [Indexed: 11/24/2022]
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Greenwood AI, Rogals MJ, De S, Lu KP, Kovrigin EL, Nicholson LK. Complete determination of the Pin1 catalytic domain thermodynamic cycle by NMR lineshape analysis. JOURNAL OF BIOMOLECULAR NMR 2011; 51:21-34. [PMID: 21947912 PMCID: PMC3491808 DOI: 10.1007/s10858-011-9538-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2011] [Accepted: 07/11/2011] [Indexed: 05/06/2023]
Abstract
The phosphorylation-specific peptidyl-prolyl isomerase Pin1 catalyzes the isomerization of the peptide bond preceding a proline residue between cis and trans isomers. To best understand the mechanisms of Pin1 regulation, rigorous enzymatic assays of isomerization are required. However, most measures of isomerase activity require significant constraints on substrate sequence and only yield rate constants for the cis isomer, [Formula: see text] and apparent Michaelis constants, [Formula: see text]. By contrast, NMR lineshape analysis is a powerful tool for determining microscopic rates and populations of each state in a complex binding scheme. The isolated catalytic domain of Pin1 was employed as a first step towards elucidating the reaction scheme of the full-length enzyme. A 24-residue phosphopeptide derived from the amyloid precurser protein intracellular domain (AICD) phosphorylated at Thr668 served as a biologically-relevant Pin1 substrate. Specific (13)C labeling at the Pin1-targeted proline residue provided multiple reporters sensitive to individual isomer binding and on-enzyme catalysis. We have performed titration experiments and employed lineshape analysis of phosphopeptide (13)C-(1)H constant time HSQC spectra to determine [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] for the catalytic domain of Pin1 acting on this AICD substrate. The on-enzyme equilibrium value of [E·trans]/[E·cis] = 3.9 suggests that the catalytic domain of Pin1 is optimized to operate on this substrate near equilibrium in the cellular context. This highlights the power of lineshape analysis for determining the microscopic parameters of enzyme catalysis, and demonstrates the feasibility of future studies of Pin1-PPIase mutants to gain insights on the catalytic mechanism of this important enzyme.
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Affiliation(s)
- Alexander I. Greenwood
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853, USA
| | - Monique J. Rogals
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853, USA
| | - Soumya De
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853, USA
| | - Kun Ping Lu
- Beth Israel Deaconess Medical Center, Harvard Medical School, Milwaukee, WI 53226, USA
| | - Evgenii L. Kovrigin
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Linda K. Nicholson
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853, USA
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Obchoei S, Weakley SM, Wongkham S, Wongkham C, Sawanyawisuth K, Yao Q, Chen C. Cyclophilin A enhances cell proliferation and tumor growth of liver fluke-associated cholangiocarcinoma. Mol Cancer 2011; 10:102. [PMID: 21871105 PMCID: PMC3173387 DOI: 10.1186/1476-4598-10-102] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Accepted: 08/26/2011] [Indexed: 12/01/2022] Open
Abstract
Background Cyclophilin A (CypA) expression is associated with malignant phenotypes in many cancers. However, the role and mechanisms of CypA in liver fluke-associated cholangiocarcinoma (CCA) are not presently known. In this study, we investigated the expression of CypA in CCA tumor tissues and CCA cell lines as well as regulation mechanisms of CypA in tumor growth using CCA cell lines. Methods CypA expression was determined by real time RT-PCR, Western blot or immunohistochemistry. CypA silence or overexpression in CCA cells was achieved using gene delivery techniques. Cell proliferation was assessed using MTS assay or Ki-67 staining. The effect of silencing CypA on CCA tumor growth was determined in nude mice. The effect of CypA knockdown on ERK1/2 activation was assessed by Western blot. Results CypA was upregulated in 68% of CCA tumor tissues. Silencing CypA significantly suppressed cell proliferation in several CCA cell lines. Likewise, inhibition of CypA peptidyl-prolyl cis-trans isomerase (PPIase) activity using cyclosporin A (CsA) decreased cell proliferation. In contrast, overexpression of CypA resulted in 30% to 35% increases in proliferation of CCA cell lines. Interestingly, neither silence nor overexpression of CypA affected cell proliferation of a non-tumor human cholangiocyte cell line, MMNK1. Suppression of CypA expression attenuated ERK1/2 activity in CCA M139 cells by using both transient and stable knockdown methods. In the in vivo study, there was a 43% reduction in weight of tumors derived from CypA-silenced CCA cell lines compared with control vector CCA tumors in mice; these tumors with stable CypA silencing showed a reduced cell proliferation. Conclusions CypA is upregulated in majority of CCA patients' tissues and confers a significant growth advantage in CCA cells. Suppression of CypA expression decreases proliferation of CCA cell lines in vitro and reduces tumor growth in the nude mouse model. Inhibition of CypA activity also reduces CCA cell proliferation. The ERK1/2 pathway may be involved in the CypA-mediated CCA cell proliferation. Thus, CypA may represent an important new therapeutic target for liver fluke-associated CCA.
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Affiliation(s)
- Sumalee Obchoei
- Molecular Surgeon Research Center, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas, USA
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Kale A, Phansopa C, Suwannachart C, Craven CJ, Rafferty JB, Kelly DJ. The virulence factor PEB4 (Cj0596) and the periplasmic protein Cj1289 are two structurally related SurA-like chaperones in the human pathogen Campylobacter jejuni. J Biol Chem 2011; 286:21254-65. [PMID: 21524997 PMCID: PMC3122185 DOI: 10.1074/jbc.m111.220442] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 04/08/2011] [Indexed: 11/06/2022] Open
Abstract
The PEB4 protein is an antigenic virulence factor implicated in host cell adhesion, invasion, and colonization in the food-borne pathogen Campylobacter jejuni. peb4 mutants have defects in outer membrane protein assembly and PEB4 is thought to act as a periplasmic chaperone. The crystallographic structure of PEB4 at 2.2-Å resolution reveals a dimer with distinct SurA-like chaperone and peptidyl-prolyl cis/trans isomerase (PPIase) domains encasing a large central cavity. Unlike SurA, the chaperone domain is formed by interlocking helices from each monomer, creating a domain-swapped architecture. PEB4 stimulated the rate of proline isomerization limited refolding of denatured RNase T(1) in a juglone-sensitive manner, consistent with parvulin-like PPIase domains. Refolding and aggregation of denatured rhodanese was significantly retarded in the presence of PEB4 or of an engineered variant specifically lacking the PPIase domain, suggesting the chaperone domain possesses a holdase activity. Using bioinformatics approaches, we identified two other SurA-like proteins (Cj1289 and Cj0694) in C. jejuni. The 2.3-Å structure of Cj1289 does not have the domain-swapped architecture of PEB4 and thus more resembles SurA. Purified Cj1289 also enhanced RNase T(1) refolding, although poorly compared with PEB4, but did not retard the refolding of denatured rhodanese. Structurally, Cj1289 is the most similar protein to SurA in C. jejuni, whereas PEB4 has most structural similarity to the Par27 protein of Bordetella pertussis. Our analysis predicts that Cj0694 is equivalent to the membrane-anchored chaperone PpiD. These results provide the first structural insights into the periplasmic assembly of outer membrane proteins in C. jejuni.
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Affiliation(s)
- Avinash Kale
- From the Department of Molecular Biology and Biotechnology, The University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, United Kingdom
| | - Chatchawal Phansopa
- From the Department of Molecular Biology and Biotechnology, The University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, United Kingdom
| | - Chatrudee Suwannachart
- From the Department of Molecular Biology and Biotechnology, The University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, United Kingdom
| | - C. Jeremy Craven
- From the Department of Molecular Biology and Biotechnology, The University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, United Kingdom
| | - John B. Rafferty
- From the Department of Molecular Biology and Biotechnology, The University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, United Kingdom
| | - David J. Kelly
- From the Department of Molecular Biology and Biotechnology, The University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, United Kingdom
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Schmidpeter PAM, Jahreis G, Geitner AJ, Schmid FX. Prolyl Isomerases Show Low Sequence Specificity toward the Residue Following the Proline. Biochemistry 2011; 50:4796-803. [DOI: 10.1021/bi200442q] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Philipp A. M. Schmidpeter
- Laboratorium für Biochemie und Bayreuther Zentrum für Molekulare Biowissenschaften, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - Günther Jahreis
- Max Planck Research Unit for Enzymology of Protein Folding, Weinbergweg 22, D-06120 Halle/Saale, Germany
| | - Anne-Juliane Geitner
- Laboratorium für Biochemie und Bayreuther Zentrum für Molekulare Biowissenschaften, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - Franz X. Schmid
- Laboratorium für Biochemie und Bayreuther Zentrum für Molekulare Biowissenschaften, Universität Bayreuth, D-95440 Bayreuth, Germany
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Peptide Bond cis/trans Isomerases: A Biocatalysis Perspective of Conformational Dynamics in Proteins. Top Curr Chem (Cham) 2011; 328:35-67. [DOI: 10.1007/128_2011_151] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Solbak SM, Reksten TR, Wray V, Bruns K, Horvli O, Raae AJ, Henklein P, Henklein P, Röder R, Mitzner D, Schubert U, Fossen T. The intriguing cyclophilin A-HIV-1 Vpr interaction: prolyl cis/trans isomerisation catalysis and specific binding. BMC STRUCTURAL BIOLOGY 2010; 10:31. [PMID: 20920334 PMCID: PMC2959089 DOI: 10.1186/1472-6807-10-31] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Accepted: 10/04/2010] [Indexed: 11/23/2022]
Abstract
Background Cyclophilin A (CypA) represents a potential target for antiretroviral therapy since inhibition of CypA suppresses human immunodeficiency virus type 1 (HIV-1) replication, although the mechanism through which CypA modulates HIV-1 infectivity still remains unclear. The interaction of HIV-1 viral protein R (Vpr) with the human peptidyl prolyl isomerase CypA is known to occur in vitro and in vivo. However, the nature of the interaction of CypA with Pro-35 of N-terminal Vpr has remained undefined. Results Characterization of the interactions of human CypA with N-terminal peptides of HIV-1 Vpr has been achieved using a combination of nuclear magnetic resonace (NMR) exchange spectroscopy and surface plasmon resonance spectroscopy (SPR). NMR data at atomic resolution indicate prolyl cis/trans isomerisation of the highly conserved proline residues Pro-5, -10, -14 and -35 of Vpr are catalyzed by human CypA and require only very low concentrations of the isomerase relative to that of the peptide substrates. Of the N-terminal peptides of Vpr only those containing Pro-35 bind to CypA in a biosensor assay. SPR studies of specific N-terminal peptides with decreasing numbers of residues revealed that a seven-residue motif centred at Pro-35 consisting of RHFPRIW, which under membrane-like solution conditions comprises the loop region connecting helix 1 and 2 of Vpr and the two terminal residues of helix 1, is sufficient to maintain strong specific binding. Conclusions Only N-terminal peptides of Vpr containing Pro-35, which appears to be vital for manifold functions of Vpr, bind to CypA in a biosensor assay. This indicates that Pro-35 is essential for a specific CypA-Vpr binding interaction, in contrast to the general prolyl cis/trans isomerisation observed for all proline residues of Vpr, which only involve transient enzyme-substrate interactions. Previously suggested models depicting CypA as a chaperone that plays a role in HIV-1 virulence are now supported by our data. In detail the SPR data of this interaction were compatible with a two-state binding interaction model that involves a conformational change during binding. This is in accord with the structural changes observed by NMR suggesting CypA catalyzes the prolyl cis/trans interconversion during binding to the RHFP35RIW motif of N-terminal Vpr.
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Affiliation(s)
- Sara M Solbak
- Department of Chemistry, University of Bergen, N-5007 Bergen, Norway
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