DOCSLIB.ORG

Ognm: Online Computation of Structural Dynamics Using the Gaussian Network Model Lee-Wei Yang1, A

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Ognm: Online Computation of Structural Dynamics Using the Gaussian Network Model Lee-Wei Yang1, A W24–W31 Nucleic Acids Research, 2006, Vol. 34, Web Server issue doi:10.1093/nar/gkl084 oGNM: online computation of structural dynamics using the Gaussian Network Model Lee-Wei Yang1, A. J. Rader1, Xiong Liu1,2, Cristopher Jon Jursa2, Shann Ching Chen1, Hassan A. Karimi2 and Ivet Bahar1,* 1Department of Computational Biology, School of Medicine and 2Department of Information Science and Telecommunications, School of Information Science, University of Pittsburgh, Pittsburgh, PA 15213, USA Received December 14, 2005; Revised January 25, 2006; Accepted March 6, 2006 ABSTRACT INTRODUCTION An assessment of the equilibrium dynamics of An emerging view in structural and molecular biology is biomolecular systems, and in particular their most that the conformational mechanisms involved in biomolecular functions are determined by the intrinsic dynamics of cooperativefluctuationsaccessibleundernativestate biomolecules, and the intrinsic dynamics are, in turn, defined conditions, is a first step towards understanding by the overall structural architecture (1). A better understand- molecular mechanisms relevant to biological func- ing of structural dynamics that underlie important biological tion. We present a web-based system, oGNM that functions has been gained in recent years by modeling enables users to calculate online the shape and biomolecular systems as biomachines. Elastic network (EN) dispersion of normal modes of motion for proteins, models and simplified normal mode analyses (NMA), have oligonucleotides and their complexes, or associated proven particularly useful to this aim, as recently reviewed biological units, using the Gaussian Network Model (2,3). Recently, we have constructed a database (DB) of (GNM). Computations with the new engine are 5–6 protein motions, iGNM (4), by using such an EN model, orders of magnitude faster than those using conven- the Gaussian Network Model (GNM) (5,6). The dynamics tional normal mode analyses. Two cases studies of 20 058 structures that were accessible in the Protein Data Bank (PDB) (7) in the fall of 2003 have been collected in the illustrate the utility of oGNM. The first shows that the iGNM DB. The present study builds on this work to introduce thermal fluctuations predicted for 1250 non-homologous an on-line calculation server, oGNM, for examining the proteins correlate well with X-ray crystallographic essential dynamics of the complete set of over 34 000 PDB data over a broad range [7.3–15 A˚ ] of inter-residue structures, as well as that of user-modified and unreleased interaction cutoff distances and the correlations structures or models. improve with increasing observation temperatures. Results from the NMAs of proteins can currently be The second study, focused on 64 oligonucleotides obtained from a number of online sources. The most detailed and oligonucleotide–protein complexes, shows that NMA is performed at the atomic level by the Molecular Vibra- good agreement with experiments is achieved by tions Evaluation Server (MoViES; http://ang.cz3.nus.edu.sg/ representing each nucleotide by three GNM nodes cgi-bin/prog/norm.pl (8). MoViES calculates the normal (as opposed to one-node-per-residue in proteins) modes and thermal vibrations for relatively small structures (<4000 heavy atoms), sending the results via email after seven along with uniform interaction ranges for all compo- days. The database of macromolecular movements (MolMovDB; nents of the complexes. These results open the way to http://molmovdb.org/) features a web submission interface for a rapid assessment of the dynamics of DNA/ calculating the five lowest frequency modes (9). WEBnm@ RNA-containing complexes. The server can be (http://www.bioinfo.no/tools/normalmodes) (10) calculates the accessed at http://ignm.ccbb.pitt.edu/GNM_Online_ slowest fourteen modes and associated deformation Calculation.htm. energies. Both systems employ the same Molecular Modeling *To whom correspondence should be addressed. Tel: +1 412 648 3333; Fax: +1 412 648 3163; Email: [email protected] Present addresses: A.J. Rader, Department of Physics, Indiana University-Purdue University Indianapolis, USA Shann Ching Chen, Department of Biomedical Engineering, Carnegie Mellon University, USA The authors wish it to be known that, in their opinion, the first two authors should be regarded as joint First Authors Ó The Author 2006. Published by Oxford University Press. All rights reserved. The online version of this article has been published under an open access model. Users are entitled to use, reproduce, disseminate, or display the open access version of this article for non-commercial purposes provided that: the original authorship is properly and fully attributed; the Journal and Oxford University Press are attributed as the original place of publication with the correct citation details given; if an article is subsequently reproduced or disseminated not in its entirety but only in part or as a derivative work this must be clearly indicated. For commercial re-use, please contact [email protected] Nucleic Acids Research, 2006, Vol. 34, Web Server issue W25 Toolkit (MMTK) package (11) that adopts a residue-level EN (24) and functional motions (2,3,25). Clearly there is a great representation. Although both provide the option of generating deal of dynamical information/patterns encoded in biomolecu- and downloading movies of these modes, they are restricted lar structures that can be efficiently extracted using the oGNM. to the analysis of single domain or single chain proteins, respectively. Online calculations for larger structures can be accomplished by elNe´mo (http://igs-server.cnrs-mrs.fr/ MATERIALS AND METHODS elnemo/index.html) (12). elNe´mo uses an alternative engine based upon the Rotation Translation Block (RTB) method (13) The Gaussian Network Model (GNM) which collapses consecutive residues into rigid blocks, each The biomolecular structure is modeled as a network of N nodes representing the nodes in a low resolution EN model. This identified by the a-carbon atoms of proteins and other selected server requires minutes, hours or longer to calculate the 100 atoms of nucleotides (see below). Drawing on the statistical slowest modes for large structures. Our oGNM server provides mechanical theory of polymer networks (26), the fluctuations online calculation of normal modes at the residue-level within of each node are assumed to be isotropic and Gaussian. The a few minutes regardless of biomolecular size. topology of the network is recorded in a N · N Kirchhoff While a large number of studies have tested and verified the matrix, G, where the off-diagonal elements are À1 if the nodes applicability of EN models to proteins, the optimal model are within a cutoff distance, rc, and zero otherwise (5,6). The and parameters for representing nucleotides remains to be diagonal elements represent the coordination number of each established (14). Two major issues in the application of EN residue. Assigning a uniform spring constant, g, to all contacts, models to biomolecules are the choice of the particular atoms the cross-correlations between the fluctuations DRi and DRj of for defining the nodes, and the cutoff distance (rc) of inter- residues i and j are evaluated as actions that define the connectors/springs between the nodes, which are carefully considered in building GNM. In an initial À1 o hDRi · DRji¼ð3kBT/gÞ½G ij 1 application of the GNM that accurately described the change in the fluctuation behavior of tRNAs nucleotides between where kB is the Boltzmann constant, T is the absolute À1 th the free- and synthetase-bound-forms (15), a single-node- temperature and [G ]ij is the ij element of the inverse of per-nucleotide, at the phosphorous atom, was used to model G (5,6). Setting j ¼ i in Equation 1, we obtain the mean-square 2 free tRNA, while two-nodes per nucleotide, identified by the (ms) fluctuations of residue i, h(DRi) i, which may be directly atoms P and O40, were used for tRNA complexed with compared to the corresponding X-ray crystallographic B-factor 2 2 synthetase. Because the distance between the P-atoms of base Bi ¼ (8p /3) h(DRi) i reported in the PDB, thus providing a pair forming nucleotides on adjacent strands varies from 13 to quantitative measure of correlation between computations and 16 s, a larger cutoff value, rp, was adopted compared to that experimental data. GNM yields the distribution of residue a (rc ¼ 7 s) commonly used for amino acid nodes (C -atoms). fluctuations; the absolute sizes are found by normalizing the exp Coarse-graining of nucleotides were found to adequately uncover results with respect to experimental B-factors (Bi ), which the global motions for translation (16,17) and replication permits us to determine g for a given choice of rc. machineries (18). The latter study adopted a three-node- The equilibrium dynamics of the structure results from the per-nucleotide model, using the P-, C2- (base) and C40- superposition of N À 1 nonzero modes found by the eigenvalue (sugar) atoms with the cutoff distances, rp and rc, set to the decomposition of G. The elements of the kth eigenvector, uk, same value. Given that the average mass of a nucleotide is describe the displacements of the residues along the kth mode approximately three times that of an amino acid, such a model coordinate, and the kth eigenvalue, lk, scales with the fre- may reflect a more consistent EN representation for the entire quency of the kth mode, where 1 < k < N À 1. The contribution network. of the kth mode to the ms fluctuations of residue i is The oGNM server offers three major advantages: (i) it is not limited to relatively small structures, or single domains; (ii) it 2 3kBT 1 T ½ðDRiÞ k ¼ ukuk 2 returns the results within seconds, i.e. its computational speed g lk ii is significantly faster compared to existing servers that may where (u u T) designates the ith diagonal element of the require minutes, hours or days to obtain the normal modes; k k ii matrix enclosed in parenthesis.
Load more

Recommended publications
  • Modal Analysis of the Lysozyme Protein Considering All-Atom and Coarse-Grained Finite Element Models
    applied sciences Article Modal Analysis of the Lysozyme Protein Considering All-Atom and Coarse-Grained Finite Element Models Gustavo Giordani 1, Domenico Scaramozzino 2,* , Ignacio Iturrioz 1, Giuseppe Lacidogna 2 and Alberto Carpinteri 2 1 Applied Mechanical Group GMAP, Engineering School, Universidade Federal do Rio Grande do Sul, Sarmento Leite 425, 90040-001 Porto Alegre, Brazil; [email protected] (G.G.); [email protected] (I.I.) 2 Department of Structural, Geotechnical and Building Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy; [email protected] (G.L.); [email protected] (A.C.) * Correspondence: [email protected]; Tel.: +39-011-090-4854 Abstract: Proteins are the fundamental entities of several organic activities. They are essential for a broad range of tasks in a way that their shapes and folding processes are crucial to achieving proper biological functions. Low-frequency modes, generally associated with collective movements at terahertz (THz) and sub-terahertz frequencies, have been appointed as critical for the conformational processes of many proteins. Dynamic simulations, such as molecular dynamics, are vastly applied by biochemical researchers in this field. However, in the last years, proposals that define the protein as a simplified elastic macrostructure have shown appealing results when dealing with this type of problem. In this context, modal analysis based on different modelization techniques, i.e., considering both an all-atom (AA) and coarse-grained (CG) representation, is proposed to analyze the hen egg-white lysozyme. This work presents new considerations and conclusions compared to previous analyses. Experimental values for the B-factor, considering all the heavy atoms or only one representative point per amino acid, are used to evaluate the validity of the numerical solutions.
    [Show full text]
  • Comparative Normal Mode Analysis of the Dynamics of DENV and ZIKV Capsids Yin-Chen Hsieh, Frédéric Poitevin, Marc Delarue, Patrice Koehl
    Comparative Normal Mode Analysis of the Dynamics of DENV and ZIKV Capsids Yin-Chen Hsieh, Frédéric Poitevin, Marc Delarue, Patrice Koehl To cite this version: Yin-Chen Hsieh, Frédéric Poitevin, Marc Delarue, Patrice Koehl. Comparative Normal Mode Analysis of the Dynamics of DENV and ZIKV Capsids. Frontiers in Molecular Biosciences, Frontiers Media, 2016, 3, pp.85. 10.3389/fmolb.2016.00085. pasteur-02174598 HAL Id: pasteur-02174598 https://hal-pasteur.archives-ouvertes.fr/pasteur-02174598 Submitted on 5 Jul 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Distributed under a Creative Commons Attribution| 4.0 International License ORIGINAL RESEARCH published: 27 December 2016 doi: 10.3389/fmolb.2016.00085 Comparative Normal Mode Analysis of the Dynamics of DENV and ZIKV Capsids Yin-Chen Hsieh 1, Frédéric Poitevin 2, 3, Marc Delarue 4 and Patrice Koehl 1* 1 Department of Computer Science and Genome Center, University of California, Davis, Davis, CA, USA, 2 Department of Structural Biology, Stanford University, Stanford, CA, USA, 3 SLAC National Accelerator Laboratory, Stanford PULSE Institute, Menlo Park, CA, USA, 4 Unit of Structural Dynamics of Macromolecules, UMR 3528 du Centre National de la Recherche Scientifique, Institut Pasteur, Paris, France Key steps in the life cycle of a virus, such as the fusion event as the virus infects a host cell and its maturation process, relate to an intricate interplay between the structure and the dynamics of its constituent proteins, especially those that define its capsid, much akin to an envelope that protects its genomic material.
    [Show full text]
  • Elastic Network Models for Biomolecular Dynamics: Theory and Application to Membrane Proteins and Viruses
    Chapter 7 Elastic Network Models For Biomolecular Dynamics: Theory and Application to Membrane Proteins and Viruses Timothy R. Lezon, Indira H. Shrivastava, Zheng Yang and Ivet Bahar ∗ Department of Computational Biology, School of Medicine, University of Pittsburgh, Suite 3064, Biomedical Science Tower 3, 3051 Fifth Ave., Pittsburgh, PA 15213 7.1. Introduction Elastic network models (ENMs) have over the last decade enjoyed considerable success in the study of macromolecular dynamics. These models have been used to predict the global dynamics of a variety of proteins and protein complexes, ranging in size from single enzymes to macromolecular machines (Keskin et al. 2002), ribosomes (Tama et al. 2003, Wang et al. 2004) and viral capsids (Tama & Brooks, 2002, Tama & Brooks, 2005, Rader et al . 2005). They have provided insights into a wide range of protein behaviors, such as mechanisms of allosteric regulation (Ming & Wall, 2005, Bahar et al . 2007, Chennubhotla et al . 2008), protein-protein binding (Tobi and Bahar 2005), anisotropic response to uniaxial tension and unfolding (Eyal and Bahar, 2008, Sulkowska et al . 2008), co- localization of catalytic sites and key mechanical sites (e.g., hinges) (Yang & Bahar 2005), interactions at the binding sites (Ming & Wall, 2006), and energetics (Miller et al. 2008), to name a few. ENMs allow the global motions of a molecule to be quickly calculated, making them an ideal complement to conventional molecular dynamics (MD) simulations. Increasingly, variants of ENMs are being applied to non-equilibrium situations, such as the prediction of transition pathways between functional states separated by low energy barriers (Zheng et al. 2007) or driving MD simulations (Isin et al.
    [Show full text]
  • Study of the Variability of the Native Protein Structure
    Study of the Variability of the Native Protein Structure Xusi Han, Woong-Hee Shin, Charles W Christoffer, Genki Terashi, Lyman Monroe, and Daisuke Kihara, Purdue University, West Lafayette, IN, United States r 2018 Elsevier Inc. All rights reserved. Introduction Proteins are flexible molecules. After being translated from a messenger RNA by a ribosome, a protein folds into its native structure (the structure of lowest free energy), which is suitable for carrying out its biological function. Although the native structure of a protein is stabilized by physical interactions of atoms including hydrogen bonds, disulfide bonds between cysteine residues, van der Waals interactions, electrostatic interactions, and solvation (interactions with solvent), the structure still admits flexible motions. Motions include those of side-chains, and some parts of main-chains, especially regions that do not form the secondary structures, which are often called loop regions. In many cases, the flexibility of proteins plays an important or essential role in the biological functions of the proteins. For example, for some enzymes, such as triosephosphate isomerase (Derreumaux and Schlick, 1998), loop regions that exist in vicinity of active (i.e., enzymatic reaction) sites, takes part in binding and holding a ligand molecule. Transporters, such as maltose transporter (Chen, 2013), are known to make large open-close motions to transfer ligand molecules across the cellular membrane. For many motor proteins, such as myosin V that “walk” along actin filament as observed in muscle contraction (Kodera and Ando, 2014), flexibility is the central for their functions. Reflecting such intrinsic flexibility of protein structures, differences are observed in protein tertiary structures determined by experimental methods such as X-ray crystallography, nuclear magnetic resonance (NMR) when they are solved under different conditions.
    [Show full text]
  • New Generation of Elastic Network Models
    Available online at www.sciencedirect.com ScienceDirect New generation of elastic network models Jose´ Ramo´ n Lo´ pez-Blanco and Pablo Chaco´ n The intrinsic flexibility of proteins and nucleic acids can be the years to be an effective approach to understanding grasped from remarkably simple mechanical models of the intrinsic dynamics of biomolecules [5,6 ,7]. particles connected by springs. In recent decades, Elastic Network Models (ENMs) combined with Normal Model Analysis Although there are many variations to reduce the complex widely confirmed their ability to predict biologically relevant biomolecular structures into a network of nodes and motions of biomolecules and soon became a popular springs, the basic assumption (and limitation) of ENMs methodology to reveal large-scale dynamics in multiple is that the potential energy is described by a quadratic structural biology scenarios. The simplicity, robustness, low function around a minimum energy conformation: computational cost, and relatively high accuracy are the X 0 2 reasons behind the success of ENMs. This review focuses on V ¼ KijðrijÀrijÞ (1) recent advances in the development and application of ENMs, i < j paying particular attention to combinations with experimental where the superindex 0 indicates the initial conformation, data. Successful application scenarios include large r is the distance between atoms i and j, and K is a spring macromolecular machines, structural refinement, docking, and ij ij stiffness function. The intrinsic dynamics of an ENM is evolutionary conservation. mostly assessed by NMA. In this classical mechanics Address technique, all the complex motions around an initial Department of Biological Chemical Physics, Rocasolano Physical Chemistry Institute C.S.I.C., Serrano 119, 28006 Madrid, Spain conformation are decoupled into a linear combination of orthogonal basis vectors, the so-called normal modes.
    [Show full text]
  • Protein Elastic Network Models and the Ranges of Cooperativity
    Protein elastic network models and the ranges of cooperativity Lei Yanga,b,c, Guang Songa,c,d, and Robert L. Jernigana,b,c,1 aBioinformatics and Computational Biology Program, bDepartment of Biochemistry, Biophysics and Molecular Biology, cL. H. Baker Center for Bioinformatics and Biological Statistics, and dDepartment of Computer Science, Iowa State University, Ames, IA 50011 Edited by Ken A. Dill, University of California, San Francisco, CA, and approved June 3, 2009 (received for review February 26, 2009) Elastic network models (ENMs) are entropic models that have Previous studies have shown that in many cases, GNM- demonstrated in many previous studies their abilities to capture predicted B-factors are in quite good agreement with the overall the important internal motions, with comparisons having experimental B-factors determined by crystallographers (8–11). been made against crystallographic B-factors and NMR conforma- Kundu et al. (10) studied 113 X-ray protein structures and found tional variabilities. ENMs have become an increasingly important that GNM is able to predict the experimental B-factors well, tool and have been widely used to comprehend protein dynamics, yielding an average correlation between prediction and experi- function, and even conformational changes. However, reliance ment of Ϸ0.59. The results of Sen et al. showed that the upon an arbitrary cutoff distance to delimit the range of interac- correlations between experimental B-factors and the GNM- tions has presented a drawback for these models, because the predicted values are quite similar at either coarse-grained or optimal cutoff values can differ somewhat from protein to protein atomic levels (12), which is consistent with its being overall an and can lead to quirks such as some shuffling in the order of the entropy model.
    [Show full text]
  • Components Analysis: a Review of Its Application on Molecular Dynamics Data Sarah A
    CHAPTER 13 Principal Components Analysis: A Review of its Application on Molecular Dynamics Data Sarah A. Mueller Stein,1 Anne E. Loccisano,1 Steven M. Firestine2 and Jeffrey D. Evanseck1 1Contribution from the Center for Computational Sciences and the Department of Chemistry and Biochemistry Duquesne University, 600 Forbes Avenue, Pittsburgh, PA 15282, USA 2Eugene Applebaum College of Pharmacy and Health Science, 3134 Eugene Applebaum Building, Wayne State University, 259 Mack Avenue, Detroit, MI 48201, USA Contents 1. Introduction 233 2. Multivariate methods 235 3. Principal components analysis 236 3.1. Background 236 3.2. Principal components 237 3.3. Covariance matrix 238 3.4. Index of selectivity 239 3.5. Eigenanalysis 239 3.6. Scree test dimensionality determination 240 3.7. Visualization 241 4. Essential dynamics 242 4.1. Background 242 4.2. Applications to protein systems 244 4.3. Applications to nucleic acids 244 5. Related methods 245 5.1. Independent component analysis 245 5.2. Singular value decomposition 245 6. Limitations and common errors 246 7. Conclusion 247 Acknowledgments 247 References 248 1. INTRODUCTION Molecular dynamics is a proven and powerful tool in the exploration and study of the structure and dynamics that define biomolecular energy ANNUAL REPORTS IN COMPUTATIONAL CHEMISTRY, VOLUME 2 r 2006 Elsevier B.V. ISSN: 1574 1400 DOI 10.1016/S1574 1400(06)02013 5 All rights reserved 234 S. A. M. Stein et al. landscapes [1–7]. Technological advances in simulation methodology [8–14] and computer architecture [15,16] have significantly extended both the time scale and length (size) scale of molecular dynamics trajectories [17–22].
    [Show full text]
  • PCA) of the Covariance Matrix Computed from MD Trajectories
    Supporting Information Supporting Methods Principal component analysis (PCA) of the covariance matrix computed from MD trajectories Proteins in the snapshots were iteratively superimposed onto their mean structure, <R>, and the covariance matrix, <∆R∆RT>, is constructed using a deviation matrix Q and decomposed into its corresponding eigenvalues and eigenvectors such that: < ∆퐑∆퐑T > = (푀 − 1)−1퐐퐐푇 = 퐕횲퐕푻 (S1) ∆R is the 3N-dimensional deviation vector, and Q is the 3N M matrix, where N and M are, respectively, the number of protein atoms in the analysis and the number of snapshots. Each column in Q represents the deviation of a given snapshot from the mean structure, while each element in that column is the deviation of a given atom in the x-, y- or z-dimension. V3N3N is the eigenvector matrix containing 3N eigenvectors (or principal components, PCs), each of which is 3N-dimensional. 횲 is the 3N 3N diagonal matrix of rank-ordered eigenvalues (from large to small). The snapshots of a trajectory are then projected onto the principal components to form a projection matrix U3NM as 1 퐔 = 퐕푻퐐 (S2) where the row k in U, uk = [uk,0, uk,1, …, uk,M-1], contains the projections of M snapshots onto a given PC eigenvector Vk for the k’th PC mode. Each snapshot of the protein structure is a scalar value (PC mode coordinate) on the mode k. Wiener–Khintchine theorem (WKT) In this section, we show the detailed derivations and implementations of the autocorrelation functions from the PC modes, obtained from MD simulations, using the Wiener–Khintchine theorem.
    [Show full text]
  • Elastic Network Models: Theoretical and Empirical Foundations
    Elastic Network Models: Theoretical and Empirical Foundations Yves-Henri Sanejouand Abstract Fifteen years ago Monique Tirion showed that the low-frequency normal modes of a protein are not significantly altered when non-bonded interactions are replaced by Hookean springs, for all atom pairs whose distance is smaller than a given cutoff value. Since then, it has been shown that coarse-grained versions of Tirion’s model are able to provide fair insights on many dynamical properties of biological macromolecules. In this chapter, theoretical tools required for studying these so-called Elastic Network Models are described, focusing on practical issues and, in particular, on possible artifacts. Then, an overview of some typical results that have been obtained by studying such models is given. Key words: Protein, Normal Mode Analysis, Anisotropic Network Model, Gaus- sian Network Model, Low-frequency Modes, B-factors, Thermal Motion, Confor- mational Change, Functional Motion. arXiv:1102.2402v1 [q-bio.BM] 11 Feb 2011 Yves-Henri Sanejouand CNRS-UMR 6204, Facult´e des Sciences, Nantes. e-mail: [email protected] 1 2 Y.-H. Sanejouand 1 Introduction In 1996, Monique Tirion showed that the low-frequency normal modes of a pro- tein (see section 3.1) are not significantly altered when Lennard-Jones and electro- static interactions are replaced by Hookean (harmonic) springs, for all atom pairs whose distance is smaller than a given cutoff value [1]. In the case of biological macromolecules, this seminal work happened to be the first study of an Elastic Net- work Model (ENM). The ENM considered was an all-atom one, chemical bonds and angles being kept fixed through the use of internal coordinates, as often done in previous standard normal mode studies of proteins [2, 3, 4].
    [Show full text]
  • Buried and Accessible Surface Area Control Intrinsic Protein Flexibility
    NOTICE: this is the author’s version of a work that was accepted for publication in the Journal of Molecular Biology. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in J Mol Biol 425, 3250-3263, 9 September 2013 http://dx.doi.org/10.1016/j.jmb.2013.06.019 Buried and accessible surface area control intrinsic protein flexibility Joseph A. Marsh European Bioinformatics Institute (EMBL-EBI) Wellcome Trust Genome Campus Hinxton, Cambridge CB10 1SD, United Kingdom [email protected] Keywords: protein dynamics; protein structure; protein folding; monomer; solvent accessible surface area Abbreviations used: Arel, relative solvent accessible surface area; NMR, nuclear magnetic resonance; GNM, Gaussian network model; Random Coil Index, RCI; quaternary structure, QS; RMSF, root-mean-squared fluctuations Abstract Proteins experience a wide variety of conformational dynamics that can be crucial for facilitating their diverse functions. How is the intrinsic flexibility required for these motions encoded in their three-dimensional structures? Here, the overall flexibility of a protein is demonstrated to be tightly coupled to the total amount of surface area buried within its fold. A simple proxy for this, the relative solvent accessible surface area (Arel), therefore shows excellent agreement with independent measures of global protein flexibility derived from various experimental and computational methods. Application of Arel on a large scale demonstrates its utility by revealing unique sequence and structural properties associated with intrinsic flexibility.
    [Show full text]
  • Arxiv:1806.10656V2 [Q-Bio.BM] 4 Sep 2018 Shapes of the Slowest Eigenvectors Are Nearly Identical, Not Merely Similar
    Slow Normal Modes of Proteins are Accurately Reproduced across Different Platforms Hyuntae Na,1, ∗ Daniel ben-Avraham,2 and Monique M. Tirion2, y 1Computer Science, Penn State Harrisburg, Middletown, Pennsylvania, USA 2Physics Department, Clarkson University, Potsdam, New York 13699-5820, USA Abstract The Protein Data Bank (PDB) [1] contains the atomic structures of over 105 biomolecules with better than 2.8A˚ resolution. The listing of the identities and coordinates of the atoms comprising each macromolecule permits an analysis of the slow-time vibrational response of these large systems to minor perturbations. 3D video animations of individual modes of oscillation demonstrate how regions interdigitate to create cohesive collective motions, providing a comprehensive framework for and familiarity with the overall 3D architecture. Furthermore, the isolation and representation of the softest, slowest deformation coordinates provide opportunities for the development of me- chanical models of enzyme function. The eigenvector decomposition, therefore, must be accurate, reliable as well as rapid to be generally reported upon. We obtain the eigenmodes of a 1.2A˚ 34kDa PDB entry using either exclusively heavy atoms or partly or fully reduced atomic sets; Cartesian or internal coordinates; interatomic force fields derived either from a full Cartesian potential, a reduced atomic potential or a Gaussian distance-dependent potential; and independently devel- oped software. These varied technologies are similar in that each maintains proper stereochemistry either by use of dihedral degrees of freedom which freezes bond lengths and bond angles, or by use of a full atomic potential that includes realistic bond length and angle restraints. We find that the arXiv:1806.10656v2 [q-bio.BM] 4 Sep 2018 shapes of the slowest eigenvectors are nearly identical, not merely similar.
    [Show full text]
  • Coarse-Grained Simulations and Elastic Network Models
    Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 15 October 2018 doi:10.20944/preprints201810.0329.v1 Peer-reviewed version available at Int. J. Mol. Sci. 2018, 19, 3496; doi:10.3390/ijms19113496 Review Modeling of Protein Structural Flexibility and Large- Scale Dynamics: Coarse-grained Simulations and Elastic Network Models Sebastian Kmiecik1, Maksim Kouza1,2, Aleksandra E. Badaczewska-Dawid1, Andrzej Kloczkowski2*, Andrzej Kolinski1* 1 Faculty of Chemistry, Biological and Chemical Research Center, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland; [email protected] 2 Nationwide Children's Hospital, Columbus, Ohio; [email protected] * Correspondence: [email protected]; Tel.: +48-22-55-26-365; [email protected] Abstract: Fluctuations of protein three-dimensional structures and large-scale conformational transitions are crucial for the biological function of proteins and their complexes. Experimental studies of such phenomena remain very challenging and therefore molecular modeling can be a good alternative or a valuable supporting tool for the investigation of large molecular systems and long-time events. In this mini-review, we present two alternative approaches to the coarse-grained (CG) modeling of dynamic properties of protein systems. We discuss two CG representations of polypeptide chains used for Monte Carlo dynamics simulations of protein local dynamics and conformational transitions and, on other hand, highly simplified structure-based Elastic Network Models of protein flexibility. In contrast to classical Molecular Dynamics the modeling strategies discussed here allow quite accurate modeling of much larger systems and longer time dynamic phenomena. We briefly describe the main features of these models and outline some of their applications, including modeling of near-native structure fluctuations, sampling of large regions of the protein conformational space, or possible support for the structure prediction of large proteins and their complexes.
    [Show full text]