1
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Schneider HJ. Distinction and Quantification of Noncovalent Dispersive and Hydrophobic Effects. Molecules 2024; 29:1591. [PMID: 38611870 PMCID: PMC11013637 DOI: 10.3390/molecules29071591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 03/15/2024] [Accepted: 03/19/2024] [Indexed: 04/14/2024] Open
Abstract
The possibilities of comparing computational results of noncovalent interactions with experimental data are discussed, first with respect to intramolecular interactions. For these a variety of experimental data such as heats of formation, crystal sublimation heats, comparison with energy minimized structures, and spectroscopic data are available, but until now largely have not found widespread application. Early force field and QM/MP2 calculations have already shown that the sublimation heats of hydrocarbons can be predicted with an accuracy of ±1%. Intermolecular interactions in solution or the gas phase are always accompanied by difficult to compute entropic contributions, like all associations between molecules. Experimentally observed T∆S values contribute 10% to 80% of the total ∆G, depending on interaction mechanisms within the complexes, such as, e.g., hydrogen bonding and ion pairing. Free energies ∆G derived from equilibrium measurements in solution allow us to define binding increments ∆∆G, which are additive and transferable to a variety of supramolecular complexes. Data from more than 90 equilibrium measurements of porphyrin receptors in water indicate that small alkanes do not bind to the hydrophobic flat surfaces within a measuring limit of ∆G = ±0.5 kJ/mol, and that 20 functions bearing heteroatoms show associations by dispersive interactions with up to ∆G = 8 kJ/mol, roughly as a function of their polarizability. Aromatic systems display size-dependent affinities ∆G as a linear function of the number of π-electrons.
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Affiliation(s)
- Hans-Jörg Schneider
- FR Organische Chemie, Universität des Saarlandes, D 66123 Saarbrücken, Germany
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2
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Saurabh S, Nadendla K, Purohit SS, Sivakumar PM, Cetinel S. Fuzzy Drug Targets: Disordered Proteins in the Drug-Discovery Realm. ACS OMEGA 2023; 8:9729-9747. [PMID: 36969402 PMCID: PMC10034788 DOI: 10.1021/acsomega.2c07708] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 02/17/2023] [Indexed: 06/18/2023]
Abstract
Intrinsically disordered proteins (IDPs) and regions (IDRs) form a large part of the eukaryotic proteome. Contrary to the structure-function paradigm, the disordered proteins perform a myriad of functions in vivo. Consequently, they are involved in various disease pathways and are plausible drug targets. Unlike folded proteins, that have a defined structure and well carved out drug-binding pockets that can guide lead molecule selection, the disordered proteins require alternative drug-development methodologies that are based on an acceptable picture of their conformational ensemble. In this review, we discuss various experimental and computational techniques that contribute toward understanding IDP "structure" and describe representative pursuances toward IDP-targeting drug development. We also discuss ideas on developing rational drug design protocols targeting IDPs.
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Affiliation(s)
- Suman Saurabh
- Molecular
Sciences Research Hub, Department of Chemistry, Imperial College London, London W12 0BZ, U.K.
| | - Karthik Nadendla
- Center
for Misfolding Diseases, Yusuf Hamied Department of Chemistry, Lensfield
Road, University of Cambridge, Cambridge CB2 1EW, U.K.
| | - Shubh Sanket Purohit
- Department
of Clinical Haematology, Sahyadri Superspeciality
Hospital, Pune, Maharashtra 411038, India
| | - Ponnurengam Malliappan Sivakumar
- Institute
of Research and Development, Duy Tan University, Da Nang 550000, Vietnam
- School
of Medicine and Pharmacy, Duy Tan University, Da Nang 550000, Vietnam
- Nanotechnology
Research and Application Center (SUNUM), Sabanci University, Istanbul 34956, Turkey
| | - Sibel Cetinel
- Nanotechnology
Research and Application Center (SUNUM), Sabanci University, Istanbul 34956, Turkey
- Faculty of
Engineering and Natural Sciences, Molecular Biology, Genetics and
Bioengineering Program, Sabanci University, Istanbul 34956, Turkey
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3
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Fan L, Li C, Huang ZG, Zhao J, Wu X, Liu T, Li Y, Wang J. The longitudinal neural dynamics changes of whole brain connectome during natural recovery from poststroke aphasia. NEUROIMAGE: CLINICAL 2022; 36:103190. [PMID: 36174256 PMCID: PMC9668607 DOI: 10.1016/j.nicl.2022.103190] [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: 02/25/2022] [Revised: 07/24/2022] [Accepted: 09/08/2022] [Indexed: 12/14/2022] Open
Abstract
Poststroke aphasia is one of the most dramatic functional deficits that results from direct damage of focal brain regions and dysfunction of large-scale brain networks. The reconstruction of language function depends on the hierarchical whole-brain dynamic reorganization. However, investigations into the longitudinal neural changes of large-scale brain networks for poststroke aphasia remain scarce. Here we characterize large-scale brain dynamics in left-frontal-stroke aphasia through energy landscape analysis. Using fMRI during an auditory comprehension task, we find that aphasia patients suffer serious whole-brain dynamics perturbation in the acute and subacute stages after stroke, in which the brains were restricted into two major activity patterns. Following spontaneous recovery process, the brain flexibility improved in the chronic stage. Critically, we demonstrated that the abnormal neural dynamics are correlated with the aberrant brain network coordination. Taken together, the energy landscape analysis exhibited that the acute poststroke aphasia has a constrained, low dimensional brain dynamics, which were replaced by less constrained and high dimensional dynamics at chronic aphasia. Our study provides a new perspective to profoundly understand the pathological mechanisms of poststroke aphasia.
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Affiliation(s)
- Liming Fan
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Health and Rehabilitation Science, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, PR China,National Engineering Research Center of Health Care and Medical Devices. Guangzhou, Guangdong 510500, PR China
| | - Chenxi Li
- Department of the Psychology of Military Medicine, Air Force Medical University, Xi’an, Shaanxi 710032, PR China
| | - Zi-gang Huang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Health and Rehabilitation Science, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, PR China,National Engineering Research Center of Health Care and Medical Devices. Guangzhou, Guangdong 510500, PR China
| | - Jie Zhao
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Health and Rehabilitation Science, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, PR China,National Engineering Research Center of Health Care and Medical Devices. Guangzhou, Guangdong 510500, PR China
| | - Xiaofeng Wu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Health and Rehabilitation Science, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, PR China,National Engineering Research Center of Health Care and Medical Devices. Guangzhou, Guangdong 510500, PR China
| | - Tian Liu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Health and Rehabilitation Science, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, PR China,National Engineering Research Center of Health Care and Medical Devices. Guangzhou, Guangdong 510500, PR China
| | - Youjun Li
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Health and Rehabilitation Science, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, PR China,National Engineering Research Center of Health Care and Medical Devices. Guangzhou, Guangdong 510500, PR China,Corresponding authors at: The Key Laboratory of Biomedical Information Engineering of Ministry of Education, and Institute of Biomedical Engineering, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an 710049, PR China.
| | - Jue Wang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Health and Rehabilitation Science, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, PR China,National Engineering Research Center of Health Care and Medical Devices. Guangzhou, Guangdong 510500, PR China,The Key Laboratory of Neuro-informatics & Rehabilitation Engineering of Ministry of Civil Affairs, Xi’an, Shaanxi 710049, PR China,Corresponding authors at: The Key Laboratory of Biomedical Information Engineering of Ministry of Education, and Institute of Biomedical Engineering, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an 710049, PR China.
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4
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Lindemann WR, Mijalis AJ, Alonso JL, Borbat PP, Freed JH, Arnaout MA, Pentelute BL, Ortony JH. Conformational Dynamics in Extended RGD-Containing Peptides. Biomacromolecules 2020; 21:2786-2794. [PMID: 32469507 PMCID: PMC7388056 DOI: 10.1021/acs.biomac.0c00506] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
RGD is a prolific example of a tripeptide used in biomaterials for cell adhesion, but the potency of free or surface-bound RGD tripeptide is orders-of-magnitude less than the RGD domain within natural proteins. We designed a set of peptides with varying lengths, composed of fragments of fibronectin protein whose central three residues are RGD, in order to vary their conformational behavior without changing the binding site's chemical environment. With these peptides, we measure the conformational dynamics and transient structure of the active site. Our studies reveal how flanking residues affect conformational behavior and integrin binding. We find that disorder of the binding site is important to the potency of RGD peptides and that transient hydrogen bonding near the RGD site affects both the energy landscape roughness of the peptides and peptide binding. This phenomenon is independent of longer-range folding interactions and helps explain why short binding sequences, including RGD itself, do not fully replicate the integrin-targeting properties of extracellular matrix proteins. Our studies reinforce that peptide binding is a holistic event and fragments larger than those directly involved in binding should be considered in the design of peptide epitopes for functional biomaterials.
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Affiliation(s)
- William R Lindemann
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Alexander J Mijalis
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - José L Alonso
- Leukocyte Biology and Inflammation Program, Division of Nephrology and Department of Medicine, Massachusetts General Hospital, 149 13th Street, Charlestown, Massachusetts 02129, United States
- Harvard Medical School, 25 Shattuck Street, Boston, Massachusetts 02115, United States
| | - Peter P Borbat
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
| | - Jack H Freed
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
| | - M Amin Arnaout
- Leukocyte Biology and Inflammation Program, Division of Nephrology and Department of Medicine, Massachusetts General Hospital, 149 13th Street, Charlestown, Massachusetts 02129, United States
- Harvard Medical School, 25 Shattuck Street, Boston, Massachusetts 02115, United States
| | - Bradley L Pentelute
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Julia H Ortony
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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5
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Lindemann WR, Evans ED, Mijalis AJ, Saouaf OM, Pentelute BL, Ortony JH. Quantifying residue-specific conformational dynamics of a highly reactive 29-mer peptide. Sci Rep 2020; 10:2597. [PMID: 32054898 PMCID: PMC7018720 DOI: 10.1038/s41598-020-59047-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 01/22/2020] [Indexed: 11/19/2022] Open
Abstract
Understanding structural transitions within macromolecules remains an important challenge in biochemistry, with important implications for drug development and medicine. Insight into molecular behavior often requires residue-specific dynamics measurement at micromolar concentrations. We studied MP01-Gen4, a library peptide selected to rapidly undergo bioconjugation, by using electron paramagnetic resonance (EPR) to measure conformational dynamics. We mapped the dynamics of MP01-Gen4 with residue-specificity and identified the regions involved in a structural transformation related to the conjugation reaction. Upon reaction, the conformational dynamics of residues near the termini slow significantly more than central residues, indicating that the reaction induces a structural transition far from the reaction site. Arrhenius analysis demonstrates a nearly threefold decrease in the activation energy of conformational diffusion upon reaction (8.0 kBT to 3.4 kBT), which occurs across the entire peptide, independently of residue position. This novel approach to EPR spectral analysis provides insight into the positional extent of disorder and the nature of the energy landscape of a highly reactive, intrinsically disordered library peptide before and after conjugation.
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Affiliation(s)
- William R Lindemann
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts, 02139, United States
| | - Ethan D Evans
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts, 02139, United States
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139, United States
| | - Alexander J Mijalis
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts, 02139, United States
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, 02115, USA
| | - Olivia M Saouaf
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts, 02139, United States
- Department of Materials Science and Engineering, Stanford University, 496 Lomita Mall, Stanford, California, 94305, United States
| | - Bradley L Pentelute
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts, 02139, United States
| | - Julia H Ortony
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts, 02139, United States.
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6
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Garland J. Unravelling the complexity of signalling networks in cancer: A review of the increasing role for computational modelling. Crit Rev Oncol Hematol 2017; 117:73-113. [PMID: 28807238 DOI: 10.1016/j.critrevonc.2017.06.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 06/01/2017] [Accepted: 06/08/2017] [Indexed: 02/06/2023] Open
Abstract
Cancer induction is a highly complex process involving hundreds of different inducers but whose eventual outcome is the same. Clearly, it is essential to understand how signalling pathways and networks generated by these inducers interact to regulate cell behaviour and create the cancer phenotype. While enormous strides have been made in identifying key networking profiles, the amount of data generated far exceeds our ability to understand how it all "fits together". The number of potential interactions is astronomically large and requires novel approaches and extreme computation methods to dissect them out. However, such methodologies have high intrinsic mathematical and conceptual content which is difficult to follow. This review explains how computation modelling is progressively finding solutions and also revealing unexpected and unpredictable nano-scale molecular behaviours extremely relevant to how signalling and networking are coherently integrated. It is divided into linked sections illustrated by numerous figures from the literature describing different approaches and offering visual portrayals of networking and major conceptual advances in the field. First, the problem of signalling complexity and data collection is illustrated for only a small selection of known oncogenes. Next, new concepts from biophysics, molecular behaviours, kinetics, organisation at the nano level and predictive models are presented. These areas include: visual representations of networking, Energy Landscapes and energy transfer/dissemination (entropy); diffusion, percolation; molecular crowding; protein allostery; quinary structure and fractal distributions; energy management, metabolism and re-examination of the Warburg effect. The importance of unravelling complex network interactions is then illustrated for some widely-used drugs in cancer therapy whose interactions are very extensive. Finally, use of computational modelling to develop micro- and nano- functional models ("bottom-up" research) is highlighted. The review concludes that computational modelling is an essential part of cancer research and is vital to understanding network formation and molecular behaviours that are associated with it. Its role is increasingly essential because it is unravelling the huge complexity of cancer induction otherwise unattainable by any other approach.
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Affiliation(s)
- John Garland
- Manchester Interdisciplinary Biocentre, Manchester University, Manchester, UK.
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7
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Volk M, Milanesi L, Waltho JP, Hunter CA, Beddard GS. The roughness of the protein energy landscape results in anomalous diffusion of the polypeptide backbone. Phys Chem Chem Phys 2015; 17:762-82. [DOI: 10.1039/c4cp03058c] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Recombination of photolysed protein disulfide bonds confirms subdiffusional backbone motion and measures the roughness of the protein's energy landscape.
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Affiliation(s)
- Martin Volk
- Department of Chemistry
- University of Liverpool
- Liverpool
- UK
| | - Lilia Milanesi
- School of Chemical and Biological Sciences
- Queen Mary
- University of London
- London
- UK
| | - Jonathan P. Waltho
- Department of Molecular Biology and Biotechnology
- University of Sheffield
- Sheffield
- UK
- Manchester Institute of Biotechnology
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8
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Li H, Xie Y, Liu C, Liu S. Physicochemical bases for protein folding, dynamics, and protein-ligand binding. SCIENCE CHINA-LIFE SCIENCES 2014; 57:287-302. [PMID: 24554472 DOI: 10.1007/s11427-014-4617-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Accepted: 09/27/2013] [Indexed: 01/02/2023]
Abstract
Proteins are essential parts of living organisms and participate in virtually every process within cells. As the genomic sequences for increasing number of organisms are completed, research into how proteins can perform such a variety of functions has become much more intensive because the value of the genomic sequences relies on the accuracy of understanding the encoded gene products. Although the static three-dimensional structures of many proteins are known, the functions of proteins are ultimately governed by their dynamic characteristics, including the folding process, conformational fluctuations, molecular motions, and protein-ligand interactions. In this review, the physicochemical principles underlying these dynamic processes are discussed in depth based on the free energy landscape (FEL) theory. Questions of why and how proteins fold into their native conformational states, why proteins are inherently dynamic, and how their dynamic personalities govern protein functions are answered. This paper will contribute to the understanding of structure-function relationship of proteins in the post-genome era of life science research.
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Affiliation(s)
- HuiMin Li
- School of Mathematics and Computer Science, Yunnan University of Nationalities, Kunming, 650500, China
- Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of Ministry of Education, Yunnan University, Kunming, 650091, China
| | - YueHui Xie
- Teaching and Research Section of Computer, Department of Basic Medical, Kunming Medical University, Kunming, 650031, China
- Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of Ministry of Education, Yunnan University, Kunming, 650091, China
| | - CiQuan Liu
- Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of Ministry of Education, Yunnan University, Kunming, 650091, China
- Southwest Biological Diversity Laboratory, Kunming Branch of Chinese Academy of Sciences, Kunming, 650223, China
| | - ShuQun Liu
- Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of Ministry of Education, Yunnan University, Kunming, 650091, China.
- Southwest Biological Diversity Laboratory, Kunming Branch of Chinese Academy of Sciences, Kunming, 650223, China.
- Key Laboratory for Animal Genetic Diversity and Evolution of High Education in Yunnan Province, Kunming, 650091, China.
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9
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Dagan S, Hagai T, Gavrilov Y, Kapon R, Levy Y, Reich Z. Stabilization of a protein conferred by an increase in folded state entropy. Proc Natl Acad Sci U S A 2013; 110:10628-33. [PMID: 23754389 PMCID: PMC3696814 DOI: 10.1073/pnas.1302284110] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Entropic stabilization of native protein structures typically relies on strategies that serve to decrease the entropy of the unfolded state. Here we report, using a combination of experimental and computational approaches, on enhanced thermodynamic stability conferred by an increase in the configurational entropy of the folded state. The enhanced stability is observed upon modifications of a loop region in the enzyme acylphosphatase and is achieved despite significant enthalpy losses. The modifications that lead to increased stability, as well as those that result in destabilization, however, strongly compromise enzymatic activity, rationalizing the preservation of the native loop structure even though it does not provide the protein with maximal stability or kinetic foldability.
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Affiliation(s)
| | - Tzachi Hagai
- Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yulian Gavrilov
- Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | | | - Yaakov Levy
- Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ziv Reich
- Departments of Biological Chemistry and
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10
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Whitford PC, Blanchard SC, Cate JHD, Sanbonmatsu KY. Connecting the kinetics and energy landscape of tRNA translocation on the ribosome. PLoS Comput Biol 2013; 9:e1003003. [PMID: 23555233 PMCID: PMC3605090 DOI: 10.1371/journal.pcbi.1003003] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 02/04/2013] [Indexed: 12/27/2022] Open
Abstract
Functional rearrangements in biomolecular assemblies result from diffusion across an underlying energy landscape. While bulk kinetic measurements rely on discrete state-like approximations to the energy landscape, single-molecule methods can project the free energy onto specific coordinates. With measures of the diffusion, one may establish a quantitative bridge between state-like kinetic measurements and the continuous energy landscape. We used an all-atom molecular dynamics simulation of the 70S ribosome (2.1 million atoms; 1.3 microseconds) to provide this bridge for specific conformational events associated with the process of tRNA translocation. Starting from a pre-translocation configuration, we identified sets of residues that collectively undergo rotary rearrangements implicated in ribosome function. Estimates of the diffusion coefficients along these collective coordinates for translocation were then used to interconvert between experimental rates and measures of the energy landscape. This analysis, in conjunction with previously reported experimental rates of translocation, provides an upper-bound estimate of the free-energy barriers associated with translocation. While this analysis was performed for a particular kinetic scheme of translocation, the quantitative framework is general and may be applied to energetic and kinetic descriptions that include any number of intermediates and transition states.
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Affiliation(s)
- Paul C Whitford
- Department of Physics, Northeastern University, Boston, Massachusetts, United States of America.
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11
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Wakayama J, Sugiyama S. Evaluation of Temperature Effect on the Interaction between β-Lactoglobulin and Anti-β-lactoglobulin Antibody by Atomic Force Microscopy. Biochemistry 2011; 51:32-42. [DOI: 10.1021/bi201245k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jun’ichi Wakayama
- Nano-Biotechnology Laboratory, Food
Engineering Division, National Food Research Institute, National Agriculture and Food Research Organization, 2-1-12 Kannondai, Tsukuba, Ibaraki 305-8642, Japan
| | - Shigeru Sugiyama
- Nano-Biotechnology Laboratory, Food
Engineering Division, National Food Research Institute, National Agriculture and Food Research Organization, 2-1-12 Kannondai, Tsukuba, Ibaraki 305-8642, Japan
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12
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Click TH, Ganguly D, Chen J. Intrinsically disordered proteins in a physics-based world. Int J Mol Sci 2010; 11:5292-309. [PMID: 21614208 PMCID: PMC3100817 DOI: 10.3390/ijms11125292] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Revised: 12/17/2010] [Accepted: 12/17/2010] [Indexed: 11/23/2022] Open
Abstract
Intrinsically disordered proteins (IDPs) are a newly recognized class of functional proteins that rely on a lack of stable structure for function. They are highly prevalent in biology, play fundamental roles, and are extensively involved in human diseases. For signaling and regulation, IDPs often fold into stable structures upon binding to specific targets. The mechanisms of these coupled binding and folding processes are of significant importance because they underlie the organization of regulatory networks that dictate various aspects of cellular decision-making. This review first discusses the challenge in detailed experimental characterization of these heterogeneous and dynamics proteins and the unique and exciting opportunity for physics-based modeling to make crucial contributions, and then summarizes key lessons from recent de novo simulations of the structure and interactions of several regulatory IDPs.
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Affiliation(s)
| | | | - Jianhan Chen
- Department of Biochemistry, Kansas State University, Manhattan, KS 66506, USA
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13
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The implications of gene heterozygosity for protein folding and protein turnover. J Theor Biol 2010; 265:554-64. [PMID: 20493885 DOI: 10.1016/j.jtbi.2010.05.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2009] [Revised: 04/11/2010] [Accepted: 05/17/2010] [Indexed: 12/14/2022]
Abstract
The offspring of closely related parents often suffer from inbreeding depression, sometimes resulting in a slower growth rate for inbred offspring relative to non-inbred offspring. Previous research has shown that some of the slower growth rate of inbred organisms can be attributed to the inbred organisms' increased levels of protein turnover. This paper attempts to show that the higher levels of protein turnover among inbred organisms can be attributed to accumulations of misfolded and aggregated proteins that require degradation by the inbred organisms' protein quality control systems. The accumulation of misfolded and aggregated proteins within inbred organisms are the result of more negative free energies of folding for proteins encoded at homozygous gene loci and higher concentrations of potentially aggregating non-native protein species within the cell. The theory presented here makes several quantitative predictions that suggest a connection between protein misfolding/aggregation and polyploidy that can be tested by future research.
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14
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Liu F, Nakaema M, Gruebele M. The transition state transit time of WW domain folding is controlled by energy landscape roughness. J Chem Phys 2009; 131:195101. [DOI: 10.1063/1.3262489] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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