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Zhao C, Li X, Han X, Li Z, Bian S, Zeng W, Ding M, Liang J, Jiang Q, Zhou Z, Fan Y, Zhang X, Sun Y. Molecular co-assembled strategy tuning protein conformation for cartilage regeneration. Nat Commun 2024; 15:1488. [PMID: 38374253 PMCID: PMC10876949 DOI: 10.1038/s41467-024-45703-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 02/01/2024] [Indexed: 02/21/2024] Open
Abstract
The assembly of oligopeptide and polypeptide molecules can reconstruct various ordered advanced structures through intermolecular interactions to achieve protein-like biofunction. Here, we develop a "molecular velcro"-inspired peptide and gelatin co-assembly strategy, in which amphiphilic supramolecular tripeptides are attached to the molecular chain of gelatin methacryloyl via intra-/intermolecular interactions. We perform molecular docking and dynamics simulations to demonstrate the feasibility of this strategy and reveal the advanced structural transition of the co-assembled hydrogel, which brings more ordered β-sheet content and 10-fold or more compressive strength improvement. We conduct transcriptome analysis to reveal the role of co-assembled hydrogel in promoting cell proliferation and chondrogenic differentiation. Subcutaneous implantation evaluation confirms considerably reduced inflammatory responses and immunogenicity in comparison with type I collagen. We demonstrate that bone mesenchymal stem cells-laden co-assembled hydrogel can be stably fixed in rabbit knee joint defects by photocuring, which significantly facilitates hyaline cartilage regeneration after three months. This co-assembly strategy provides an approach for developing cartilage regenerative biomaterials.
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Affiliation(s)
- Chengkun Zhao
- National Engineering Research Center for Biomaterials, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China
- College of Biomedical Engineering, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China
| | - Xing Li
- National Engineering Research Center for Biomaterials, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China
- College of Biomedical Engineering, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China
| | - Xiaowen Han
- NHC Key Laboratory of Nuclear Technology Medical Transformation, Mianyang Central Hospital, Mianyang, Sichuan, 621099, P. R. China
| | - Zhulian Li
- National Engineering Research Center for Biomaterials, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China
- College of Biomedical Engineering, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China
| | - Shaoquan Bian
- Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, P. R. China
| | - Weinan Zeng
- Department of Orthopedic Surgery and Orthopedic Research Institution, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Mingming Ding
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu, 610065, P. R. China
| | - Jie Liang
- National Engineering Research Center for Biomaterials, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China
- College of Biomedical Engineering, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China
- Sichuan Testing Center for Biomaterials and Medical Devices, Sichuan University, 29# Wangjiang Road, Chengdu, 610064, P. R. China
| | - Qing Jiang
- National Engineering Research Center for Biomaterials, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China
- College of Biomedical Engineering, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China
| | - Zongke Zhou
- Department of Orthopedic Surgery and Orthopedic Research Institution, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Yujiang Fan
- National Engineering Research Center for Biomaterials, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China
- College of Biomedical Engineering, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China
| | - Xingdong Zhang
- National Engineering Research Center for Biomaterials, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China
- College of Biomedical Engineering, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China
| | - Yong Sun
- National Engineering Research Center for Biomaterials, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China.
- College of Biomedical Engineering, Sichuan University, 29# Wangjiang Road, Chengdu, Sichuan, 610064, P. R. China.
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2
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Liu M, Das AK, Lincoff J, Sasmal S, Cheng SY, Vernon RM, Forman-Kay JD, Head-Gordon T. Configurational Entropy of Folded Proteins and Its Importance for Intrinsically Disordered Proteins. Int J Mol Sci 2021; 22:ijms22073420. [PMID: 33810353 PMCID: PMC8037987 DOI: 10.3390/ijms22073420] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 03/24/2021] [Accepted: 03/25/2021] [Indexed: 01/02/2023] Open
Abstract
Many pairwise additive force fields are in active use for intrinsically disordered proteins (IDPs) and regions (IDRs), some of which modify energetic terms to improve the description of IDPs/IDRs but are largely in disagreement with solution experiments for the disordered states. This work considers a new direction-the connection to configurational entropy-and how it might change the nature of our understanding of protein force field development to equally well encompass globular proteins, IDRs/IDPs, and disorder-to-order transitions. We have evaluated representative pairwise and many-body protein and water force fields against experimental data on representative IDPs and IDRs, a peptide that undergoes a disorder-to-order transition, for seven globular proteins ranging in size from 130 to 266 amino acids. We find that force fields with the largest statistical fluctuations consistent with the radius of gyration and universal Lindemann values for folded states simultaneously better describe IDPs and IDRs and disorder-to-order transitions. Hence, the crux of what a force field should exhibit to well describe IDRs/IDPs is not just the balance between protein and water energetics but the balance between energetic effects and configurational entropy of folded states of globular proteins.
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Affiliation(s)
- Meili Liu
- Department of Chemistry, Beijing Normal University, Beijing 100875, China;
- Pitzer Center for Theoretical Chemistry, University of California, Berkeley, CA 94720, USA; (A.K.D.); (J.L.); (S.S.); (S.Y.C.)
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
| | - Akshaya K. Das
- Pitzer Center for Theoretical Chemistry, University of California, Berkeley, CA 94720, USA; (A.K.D.); (J.L.); (S.S.); (S.Y.C.)
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
| | - James Lincoff
- Pitzer Center for Theoretical Chemistry, University of California, Berkeley, CA 94720, USA; (A.K.D.); (J.L.); (S.S.); (S.Y.C.)
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720, USA
| | - Sukanya Sasmal
- Pitzer Center for Theoretical Chemistry, University of California, Berkeley, CA 94720, USA; (A.K.D.); (J.L.); (S.S.); (S.Y.C.)
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720, USA
| | - Sara Y. Cheng
- Pitzer Center for Theoretical Chemistry, University of California, Berkeley, CA 94720, USA; (A.K.D.); (J.L.); (S.S.); (S.Y.C.)
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
| | - Robert M. Vernon
- Molecular Medicine Program, Hospital for Sick Children, Toronto, ON M5G 0A4, Canada; (R.M.V.); (J.D.F.-K.)
| | - Julie D. Forman-Kay
- Molecular Medicine Program, Hospital for Sick Children, Toronto, ON M5G 0A4, Canada; (R.M.V.); (J.D.F.-K.)
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Teresa Head-Gordon
- Pitzer Center for Theoretical Chemistry, University of California, Berkeley, CA 94720, USA; (A.K.D.); (J.L.); (S.S.); (S.Y.C.)
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720, USA
- Department of Bioengineering, University of California, Berkeley, CA 94720, USA
- Correspondence:
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3
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Bianco V, Alonso-Navarro M, Di Silvio D, Moya S, Cortajarena AL, Coluzza I. Proteins are Solitary! Pathways of Protein Folding and Aggregation in Protein Mixtures. J Phys Chem Lett 2019; 10:4800-4804. [PMID: 31373499 DOI: 10.1021/acs.jpclett.9b01753] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We present a computational and experimental study on the folding and aggregation in solutions of multiple protein mixtures at different concentrations. We show how in protein mixtures each component is capable of maintaining its folded state at densities greater than the one at which they would precipitate in single-species solutions. We demonstrate the generality of our observation over many different proteins using computer simulations capable of fully characterizing the cross-aggregation phase diagram of all the mixtures. Dynamic light scattering experiments were performed to evaluate the aggregation of two proteins, bovine serum albumin (BSA) and consensus tetratricopeptide repeat (CTPR), in solutions of one or both proteins. The experiments confirm our hypothesis and the simulations. These findings elucidate critical aspects of the cross-regulation of expression and aggregation of proteins exerted by the cell and on the evolutionary selection of folding and non-aggregating protein sequences, paving the way for new experimental tests.
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Affiliation(s)
- Valentino Bianco
- Faculty of Chemistry, Chemical Physics Deprtment, Universidad Complutense de Madrid, Plaza de las Ciencias, Ciudad Universitaria, Madrid 28040, Spain
| | | | | | - Sergio Moya
- CIC biomaGUNE, Paseo Miramon 182, 20014 San Sebastian, Spain
| | - Aitziber L Cortajarena
- CIC biomaGUNE, Paseo Miramon 182, 20014 San Sebastian, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
| | - Ivan Coluzza
- CIC biomaGUNE, Paseo Miramon 182, 20014 San Sebastian, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
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4
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Coluzza I. Computational protein design: a review. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:143001. [PMID: 28140371 DOI: 10.1088/1361-648x/aa5c76] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Proteins are one of the most versatile modular assembling systems in nature. Experimentally, more than 110 000 protein structures have been identified and more are deposited every day in the Protein Data Bank. Such an enormous structural variety is to a first approximation controlled by the sequence of amino acids along the peptide chain of each protein. Understanding how the structural and functional properties of the target can be encoded in this sequence is the main objective of protein design. Unfortunately, rational protein design remains one of the major challenges across the disciplines of biology, physics and chemistry. The implications of solving this problem are enormous and branch into materials science, drug design, evolution and even cryptography. For instance, in the field of drug design an effective computational method to design protein-based ligands for biological targets such as viruses, bacteria or tumour cells, could give a significant boost to the development of new therapies with reduced side effects. In materials science, self-assembly is a highly desired property and soon artificial proteins could represent a new class of designable self-assembling materials. The scope of this review is to describe the state of the art in computational protein design methods and give the reader an outline of what developments could be expected in the near future.
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Affiliation(s)
- Ivan Coluzza
- Computational Physics, Faculty of Physics, University of Vienna, Vienna, Austria
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5
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Bianchi E, Capone B, Coluzza I, Rovigatti L, van Oostrum PDJ. Limiting the valence: advancements and new perspectives on patchy colloids, soft functionalized nanoparticles and biomolecules. Phys Chem Chem Phys 2017; 19:19847-19868. [DOI: 10.1039/c7cp03149a] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Artistic representation of limited valance units consisting of a soft core (in blue) and a small number of flexible bonding patches (in orange).
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Affiliation(s)
- Emanuela Bianchi
- Faculty of Physics
- University of Vienna
- A-1090 Vienna
- Austria
- Institute for Theoretical Physics
| | - Barbara Capone
- Faculty of Physics
- University of Vienna
- A-1090 Vienna
- Austria
- Dipartimento di Scienze
| | - Ivan Coluzza
- Faculty of Physics
- University of Vienna
- A-1090 Vienna
- Austria
| | - Lorenzo Rovigatti
- Faculty of Physics
- University of Vienna
- A-1090 Vienna
- Austria
- Rudolf Peierls Centre for Theoretical Physics
| | - Peter D. J. van Oostrum
- Department of Nanobiotechnology
- Institute for Biologically Inspired Materials
- University of Natural Resources and Life Sciences
- A-1190 Vienna
- Austria
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6
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Kaushik R, Jayaram B. Structural difficulty index: a reliable measure for modelability of protein tertiary structures. Protein Eng Des Sel 2016; 29:391-7. [PMID: 27334454 DOI: 10.1093/protein/gzw025] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Accepted: 05/27/2016] [Indexed: 11/13/2022] Open
Abstract
The success in protein tertiary-structure prediction is considered to be a function of coverage and similarity/identity of their sequences with suitable templates in the structural databases. However, this measure of modelability of a protein sequence into its structure may be misleading. Addressing this limitation, we propose here a 'structural difficulty (SD)' index, which is derived from secondary structures, homology and physicochemical features of protein sequences. The SD index reflects the capability of predicting accurate structures and helps to assess the potential for developing proteome level structural databases for various organisms with some of the best methodologies available currently. For instance, the plausibility of populating the structural database of human proteome with reliable quality structures under 3 Å root mean square deviation from the corresponding natives is found to be ∼37% of a total of 11 084 manually curated soluble proteins and ∼64% for all annotated and reviewed unique soluble protein (344 661 sequences) of UniProtKB. Also for 77 human pathogenic viruses comprising 2365 globular viral proteins out of which only 162 structures are solved experimentally, SD index scores 1336 proteins in the modelable zone. Availability of reliable protein structures may prove a crucial aid in developing species-wise structural proteomic databases for accelerating function annotation and for drug development endeavors.
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Affiliation(s)
- Rahul Kaushik
- Kusuma School of Biological Sciences, Indian Institute of Technology, Hauz Khas, New Delhi 110016, India Supercomputing Facility for Bioinformatics & Computational Biology, Indian Institute of Technology, Hauz Khas, New Delhi 110016, India
| | - B Jayaram
- Kusuma School of Biological Sciences, Indian Institute of Technology, Hauz Khas, New Delhi 110016, India Supercomputing Facility for Bioinformatics & Computational Biology, Indian Institute of Technology, Hauz Khas, New Delhi 110016, India Department of Chemistry, Indian Institute of Technology, Hauz Khas, New Delhi 110016, India
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7
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Maximova T, Moffatt R, Ma B, Nussinov R, Shehu A. Principles and Overview of Sampling Methods for Modeling Macromolecular Structure and Dynamics. PLoS Comput Biol 2016; 12:e1004619. [PMID: 27124275 PMCID: PMC4849799 DOI: 10.1371/journal.pcbi.1004619] [Citation(s) in RCA: 132] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Investigation of macromolecular structure and dynamics is fundamental to understanding how macromolecules carry out their functions in the cell. Significant advances have been made toward this end in silico, with a growing number of computational methods proposed yearly to study and simulate various aspects of macromolecular structure and dynamics. This review aims to provide an overview of recent advances, focusing primarily on methods proposed for exploring the structure space of macromolecules in isolation and in assemblies for the purpose of characterizing equilibrium structure and dynamics. In addition to surveying recent applications that showcase current capabilities of computational methods, this review highlights state-of-the-art algorithmic techniques proposed to overcome challenges posed in silico by the disparate spatial and time scales accessed by dynamic macromolecules. This review is not meant to be exhaustive, as such an endeavor is impossible, but rather aims to balance breadth and depth of strategies for modeling macromolecular structure and dynamics for a broad audience of novices and experts.
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Affiliation(s)
- Tatiana Maximova
- Department of Computer Science, George Mason University, Fairfax, Virginia, United States of America
| | - Ryan Moffatt
- Department of Computer Science, George Mason University, Fairfax, Virginia, United States of America
| | - Buyong Ma
- Basic Science Program, Leidos Biomedical Research, Inc. Cancer and Inflammation Program, National Cancer Institute, Frederick, Maryland, United States of America
| | - Ruth Nussinov
- Basic Science Program, Leidos Biomedical Research, Inc. Cancer and Inflammation Program, National Cancer Institute, Frederick, Maryland, United States of America
- Sackler Institute of Molecular Medicine, Department of Human Genetics and Molecular Medicine, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Amarda Shehu
- Department of Computer Science, George Mason University, Fairfax, Virginia, United States of America
- Department of Biongineering, George Mason University, Fairfax, Virginia, United States of America
- School of Systems Biology, George Mason University, Manassas, Virginia, United States of America
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8
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Hierarchical Conformational Analysis of Native Lysozyme Based on Sub-Millisecond Molecular Dynamics Simulations. PLoS One 2015; 10:e0129846. [PMID: 26057625 PMCID: PMC4461368 DOI: 10.1371/journal.pone.0129846] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 05/12/2015] [Indexed: 11/19/2022] Open
Abstract
Hierarchical organization of free energy landscape (FEL) for native globular proteins has been widely accepted by the biophysics community. However, FEL of native proteins is usually projected onto one or a few dimensions. Here we generated collectively 0.2 milli-second molecular dynamics simulation trajectories in explicit solvent for hen egg white lysozyme (HEWL), and carried out detailed conformational analysis based on backbone torsional degrees of freedom (DOF). Our results demonstrated that at micro-second and coarser temporal resolutions, FEL of HEWL exhibits hub-like topology with crystal structures occupying the dominant structural ensemble that serves as the hub of conformational transitions. However, at 100ns and finer temporal resolutions, conformational substates of HEWL exhibit network-like topology, crystal structures are associated with kinetic traps that are important but not dominant ensembles. Backbone torsional state transitions on time scales ranging from nanoseconds to beyond microseconds were found to be associated with various types of molecular interactions. Even at nanoseconds temporal resolution, the number of conformational substates that are of statistical significance is quite limited. These observations suggest that detailed analysis of conformational substates at multiple temporal resolutions is both important and feasible. Transition state ensembles among various conformational substates at microsecond temporal resolution were observed to be considerably disordered. Life times of these transition state ensembles are found to be nearly independent of the time scales of the participating torsional DOFs.
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Abstract
Kinetic folding of the large two-domain maltose binding protein (MBP; 370 residues) was studied at high structural resolution by an advanced hydrogen-exchange pulse-labeling mass-spectrometry method (HX MS). Dilution into folding conditions initiates a fast molecular collapse into a polyglobular conformation (<20 ms), determined by various methods including small angle X-ray scattering. The compaction produces a structurally heterogeneous state with widespread low-level HX protection and spectroscopic signals that match the equilibrium melting posttransition-state baseline. In a much slower step (7-s time constant), all of the MBP molecules, although initially heterogeneously structured, form the same distinct helix plus sheet folding intermediate with the same time constant. The intermediate is composed of segments that are distant in the MBP sequence but adjacent in the native protein where they close the longest residue-to-residue contact. Segments that are most HX protected in the early molecular collapse do not contribute to the initial intermediate, whereas the segments that do participate are among the less protected. The 7-s intermediate persists through the rest of the folding process. It contains the sites of three previously reported destabilizing mutations that greatly slow folding. These results indicate that the intermediate is an obligatory step on the MBP folding pathway. MBP then folds to the native state on a longer time scale (~100 s), suggestively in more than one step, the first of which forms structure adjacent to the 7-s intermediate. These results add a large protein to the list of proteins known to fold through distinct native-like intermediates in distinct pathways.
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10
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Meuzelaar H, Marino KA, Huerta-Viga A, Panman MR, Smeenk LEJ, Kettelarij AJ, van Maarseveen JH, Timmerman P, Bolhuis PG, Woutersen S. Folding dynamics of the Trp-cage miniprotein: evidence for a native-like intermediate from combined time-resolved vibrational spectroscopy and molecular dynamics simulations. J Phys Chem B 2013; 117:11490-501. [PMID: 24050152 DOI: 10.1021/jp404714c] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Trp-cage is a synthetic 20-residue miniprotein which folds rapidly and spontaneously to a well-defined globular structure more typical of larger proteins. Due to its small size and fast folding, it is an ideal model system for experimental and theoretical investigations of protein folding mechanisms. However, Trp-cage's exact folding mechanism is still a matter of debate. Here we investigate Trp-cage's relaxation dynamics in the amide I' spectral region (1530-1700 cm(-1)) using time-resolved infrared spectroscopy. Residue-specific information was obtained by incorporating an isotopic label ((13)C═(18)O) into the amide carbonyl group of residue Gly11, thereby spectrally isolating an individual 310-helical residue. The folding-unfolding equilibrium is perturbed using a nanosecond temperature-jump (T-jump), and the subsequent re-equilibration is probed by observing the time-dependent vibrational response in the amide I' region. We observe bimodal relaxation kinetics with time constants of 100 ± 10 and 770 ± 40 ns at 322 K, suggesting that the folding involves an intermediate state, the character of which can be determined from the time- and frequency-resolved data. We find that the relaxation dynamics close to the melting temperature involve fast fluctuations in the polyproline II region, whereas the slower process can be attributed to conformational rearrangements due to the global (un)folding transition of the protein. Combined analysis of our T-jump data and molecular dynamics simulations indicates that the formation of a well-defined α-helix precedes the rapid formation of the hydrophobic cage structure, implying a native-like folding intermediate, that mainly differs from the folded conformation in the orientation of the C-terminal polyproline II helix relative to the N-terminal part of the backbone. We find that the main free-energy barrier is positioned between the folding intermediate and the unfolded state ensemble, and that it involves the formation of the α-helix, the 310-helix, and the Asp9-Arg16 salt bridge. Our results suggest that at low temperature (T ≪ Tm) a folding path via formation of α-helical contacts followed by hydrophobic clustering becomes more important.
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Affiliation(s)
- Heleen Meuzelaar
- Van't Hoff Institute for Molecular Sciences, University of Amsterdam , Science Park 904, 1098 XH Amsterdam, The Netherlands
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11
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Adhikari AN, Freed KF, Sosnick TR. Simplified protein models: predicting folding pathways and structure using amino acid sequences. PHYSICAL REVIEW LETTERS 2013; 111:028103. [PMID: 23889448 PMCID: PMC4047675 DOI: 10.1103/physrevlett.111.028103] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2013] [Indexed: 06/02/2023]
Abstract
We demonstrate the ability of simultaneously determining a protein's folding pathway and structure using a properly formulated model without prior knowledge of the native structure. Our model employs a natural coordinate system for describing proteins and a search strategy inspired by the observation that real proteins fold in a sequential fashion by incrementally stabilizing nativelike substructures or "foldons." Comparable folding pathways and structures are obtained for the twelve proteins recently studied using atomistic molecular dynamics simulations [K. Lindorff-Larsen, S. Piana, R. O. Dror, D. E. Shaw, Science 334, 517 (2011)], with our calculations running several orders of magnitude faster. We find that nativelike propensities in the unfolded state do not necessarily determine the order of structure formation, a departure from a major conclusion of the molecular dynamics study. Instead, our results support a more expansive view wherein intrinsic local structural propensities may be enhanced or overridden in the folding process by environmental context. The success of our search strategy validates it as an expedient mechanism for folding both in silico and in vivo.
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Affiliation(s)
- Aashish N. Adhikari
- Department of Chemistry, University of Chicago, Chicago, IL 60637 USA
- James Franck Institute, University of Chicago, Chicago, IL 60637 USA
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637 USA
| | - Karl F. Freed
- Department of Chemistry, University of Chicago, Chicago, IL 60637 USA
- James Franck Institute, University of Chicago, Chicago, IL 60637 USA
- Computation Institute, University of Chicago, Chicago, IL 60637 USA
| | - Tobin R. Sosnick
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637 USA
- Computation Institute, University of Chicago, Chicago, IL 60637 USA
- Institute for Biophysical Dynamics, University of Chicago, Chicago, IL 60637 USA
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12
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Lane TJ, Shukla D, Beauchamp KA, Pande VS. To milliseconds and beyond: challenges in the simulation of protein folding. Curr Opin Struct Biol 2012; 23:58-65. [PMID: 23237705 DOI: 10.1016/j.sbi.2012.11.002] [Citation(s) in RCA: 264] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 11/15/2012] [Accepted: 11/19/2012] [Indexed: 01/02/2023]
Abstract
Quantitatively accurate all-atom molecular dynamics (MD) simulations of protein folding have long been considered a holy grail of computational biology. Due to the large system sizes and long timescales involved, such a pursuit was for many years computationally intractable. Further, sufficiently accurate forcefields needed to be developed in order to realistically model folding. This decade, however, saw the first reports of folding simulations describing kinetics on the order of milliseconds, placing many proteins firmly within reach of these methods. Progress in sampling and forcefield accuracy, however, presents a new challenge: how to turn huge MD datasets into scientific understanding. Here, we review recent progress in MD simulation techniques and show how the vast datasets generated by such techniques present new challenges for analysis. We critically discuss the state of the art, including reaction coordinate and Markov state model (MSM) methods, and provide a perspective for the future.
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Affiliation(s)
- Thomas J Lane
- Department of Chemistry, Stanford University, United States
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13
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Sugai N, Heguri H, Yamamoto T, Tezuka Y. A Programmed Polymer Folding: Click and Clip Construction of Doubly Fused Tricyclic and Triply Fused Tetracyclic Polymer Topologies. J Am Chem Soc 2011; 133:19694-7. [DOI: 10.1021/ja209394m] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Naoto Sugai
- Department of Organic and Polymeric Materials, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Hiroyuki Heguri
- Department of Organic and Polymeric Materials, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Takuya Yamamoto
- Department of Organic and Polymeric Materials, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Yasuyuki Tezuka
- Department of Organic and Polymeric Materials, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan
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