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Fujisawa T, Shingae T, Ren J, Haraguchi S, Hanamoto T, Hoff WD, Unno M. Spectroscopic Validation of Crystallographic Structures of a Protein Active Site by Chiroptical Spectroscopy. J Phys Chem Lett 2023; 14:9304-9309. [PMID: 37816034 DOI: 10.1021/acs.jpclett.3c01954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/12/2023]
Abstract
Out-of-plane distortions of a cofactor molecule in a protein active site are functionally important, and in photoreceptors, it has been proposed that they are crucial for spectral tuning and energy storage in photocycle intermediates. However, these subtle structural features are often beyond the grasp of structural biology. This issue is strikingly exemplified by photoactive yellow protein: its 14 independently determined crystal structures exhibit considerable differences in the dihedral angles defining the chromophore geometry, even though most of these are at excellent resolution. Here we developed a strategy to verify cofactor distortions in crystal structures by using quantum chemical calculations and chiroptical spectroscopy, particularly Raman optical activity and electronic circular dichroism spectroscopies. Based on this approach, we identify seven crystal structures with the chromophore geometries inconsistent with the experimentally observed data. The strategy implemented here promises to be widely applicable to uncovering cofactor distortions at active sites and to studies of reaction intermediates.
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Affiliation(s)
- Tomotsumi Fujisawa
- Department of Chemistry and Applied Chemistry, Faculty of Science and Engineering, Saga University, Saga 840-8502, Japan
| | - Takahito Shingae
- Department of Chemistry and Applied Chemistry, Faculty of Science and Engineering, Saga University, Saga 840-8502, Japan
| | - Jie Ren
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Shojiro Haraguchi
- Department of Chemistry and Applied Chemistry, Faculty of Science and Engineering, Saga University, Saga 840-8502, Japan
| | - Takeshi Hanamoto
- Department of Chemistry and Applied Chemistry, Faculty of Science and Engineering, Saga University, Saga 840-8502, Japan
| | - Wouter D Hoff
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Masashi Unno
- Department of Chemistry and Applied Chemistry, Faculty of Science and Engineering, Saga University, Saga 840-8502, Japan
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2
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Yin F, Butts CT. Highly scalable maximum likelihood and conjugate Bayesian inference for ERGMs on graph sets with equivalent vertices. PLoS One 2022; 17:e0273039. [PMID: 36018834 PMCID: PMC9417041 DOI: 10.1371/journal.pone.0273039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 08/02/2022] [Indexed: 11/18/2022] Open
Abstract
The exponential family random graph modeling (ERGM) framework provides a highly flexible approach for the statistical analysis of networks (i.e., graphs). As ERGMs with dyadic dependence involve normalizing factors that are extremely costly to compute, practical strategies for ERGMs inference generally employ a variety of approximations or other workarounds. Markov Chain Monte Carlo maximum likelihood (MCMC MLE) provides a powerful tool to approximate the maximum likelihood estimator (MLE) of ERGM parameters, and is generally feasible for typical models on single networks with as many as a few thousand nodes. MCMC-based algorithms for Bayesian analysis are more expensive, and high-quality answers are challenging to obtain on large graphs. For both strategies, extension to the pooled case—in which we observe multiple networks from a common generative process—adds further computational cost, with both time and memory scaling linearly in the number of graphs. This becomes prohibitive for large networks, or cases in which large numbers of graph observations are available. Here, we exploit some basic properties of the discrete exponential families to develop an approach for ERGM inference in the pooled case that (where applicable) allows an arbitrarily large number of graph observations to be fit at no additional computational cost beyond preprocessing the data itself. Moreover, a variant of our approach can also be used to perform Bayesian inference under conjugate priors, again with no additional computational cost in the estimation phase. The latter can be employed either for single graph observations, or for observations from graph sets. As we show, the conjugate prior is easily specified, and is well-suited to applications such as regularization. Simulation studies show that the pooled method leads to estimates with good frequentist properties, and posterior estimates under the conjugate prior are well-behaved. We demonstrate the usefulness of our approach with applications to pooled analysis of brain functional connectivity networks and to replicated x-ray crystal structures of hen egg-white lysozyme.
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Affiliation(s)
- Fan Yin
- Department of Statistics, University of California at Irvine, Irvine, CA, United States of America
| | - Carter T. Butts
- Department of Sociology, Statistics, Computer Science, and EECS and Institute for Mathematical Behavioral Sciences, University of California at Irvine, Irvine, CA, United States of America
- * E-mail:
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3
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Banerjee S, Mitra D. Structural Basis of Design and Engineering for Advanced Plant Optogenetics. TRENDS IN PLANT SCIENCE 2020; 25:35-65. [PMID: 31699521 DOI: 10.1016/j.tplants.2019.10.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 09/12/2019] [Accepted: 10/03/2019] [Indexed: 06/10/2023]
Abstract
In optogenetics, light-sensitive proteins are specifically expressed in target cells and light is used to precisely control the activity of these proteins at high spatiotemporal resolution. Optogenetics initially used naturally occurring photoreceptors to control neural circuits, but has expanded to include carefully designed and engineered photoreceptors. Several optogenetic constructs are based on plant photoreceptors, but their application to plant systems has been limited. Here, we present perspectives on the development of plant optogenetics, considering different levels of design complexity. We discuss how general principles of light-driven signal transduction can be coupled with approaches for engineering protein folding to develop novel optogenetic tools. Finally, we explore how the use of computation, networks, circular permutation, and directed evolution could enrich optogenetics.
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Affiliation(s)
- Sudakshina Banerjee
- Department of Life Sciences, Presidency University, 86/1 College Street, Kolkata 700073, India
| | - Devrani Mitra
- Department of Life Sciences, Presidency University, 86/1 College Street, Kolkata 700073, India.
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4
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Affiliation(s)
- Alice Henley
- Department of Chemistry, University College London, London, UK
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5
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Spectroscopic ruler for measuring active-site distortions based on Raman optical activity of a hydrogen out-of-plane vibration. Proc Natl Acad Sci U S A 2018; 115:8671-8675. [PMID: 30104345 DOI: 10.1073/pnas.1806491115] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Photoactive yellow protein (PYP), from the phototrophic bacterium Halorhodospira halophila, is a small water-soluble photoreceptor protein and contains p-coumaric acid (pCA) as a chromophore. PYP has been an attractive model for studying the physical chemistry of protein active sites. Here, we explore how Raman optical activity (ROA) can be used to extract quantitative information on distortions of the pCA chromophore at the active site in PYP. We use 13C8-pCA to assign an intense signal at 826 cm-1 in the ROA spectrum of PYP to a hydrogen out-of-plane vibration of the ethylenic moiety of the chromophore. Quantum-chemical calculations based on density functional theory demonstrate that the sign of this ROA band reports the direction of the distortion in the dihedral angle about the ethylenic C=C bond, while its amplitude is proportional to the dihedral angle. These results document the ability of ROA to quantify structural deformations of a cofactor molecule embedded in a protein moiety.
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6
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Correlating structural and photochemical heterogeneity in cyanobacteriochrome NpR6012g4. Proc Natl Acad Sci U S A 2018; 115:4387-4392. [PMID: 29632180 DOI: 10.1073/pnas.1720682115] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Phytochrome photoreceptors control plant growth, development, and the shade avoidance response that limits crop yield in high-density agricultural plantings. Cyanobacteriochromes (CBCRs) are distantly related photosensory proteins that control cyanobacterial metabolism and behavior in response to light. Photoreceptors in both families reversibly photoconvert between two photostates via photoisomerization of linear tetrapyrrole (bilin) chromophores. Spectroscopic and biochemical studies have demonstrated heterogeneity in both photostates, but the structural basis for such heterogeneity remains unclear. We report solution NMR structures for both photostates of the red/green CBCR NpR6012g4 from Nostoc punctiforme In addition to identifying structural changes accompanying photoconversion, these structures reveal structural heterogeneity for residues Trp655 and Asp657 in the red-absorbing NpR6012g4 dark state, yielding two distinct environments for the phycocyanobilin chromophore. We use site-directed mutagenesis and fluorescence and absorbance spectroscopy to assign an orange-absorbing population in the NpR6012g4 dark state to the minority configuration for Asp657. This population does not undergo full, productive photoconversion, as shown by time-resolved spectroscopy and absorption spectroscopy at cryogenic temperature. Our studies thus elucidate the spectral and photochemical consequences of structural heterogeneity in a member of the phytochrome superfamily, insights that should inform efforts to improve photochemical or fluorescence quantum yields in the phytochrome superfamily.
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Mix LT, Carroll EC, Morozov D, Pan J, Gordon WR, Philip A, Fuzell J, Kumauchi M, van Stokkum I, Groenhof G, Hoff WD, Larsen DS. Excitation-Wavelength-Dependent Photocycle Initiation Dynamics Resolve Heterogeneity in the Photoactive Yellow Protein from Halorhodospira halophila. Biochemistry 2018; 57:1733-1747. [PMID: 29465990 DOI: 10.1021/acs.biochem.7b01114] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Photoactive yellow proteins (PYPs) make up a diverse class of blue-light-absorbing bacterial photoreceptors. Electronic excitation of the p-coumaric acid chromophore covalently bound within PYP results in triphasic quenching kinetics; however, the molecular basis of this behavior remains unresolved. Here we explore this question by examining the excitation-wavelength dependence of the photodynamics of the PYP from Halorhodospira halophila via a combined experimental and computational approach. The fluorescence quantum yield, steady-state fluorescence emission maximum, and cryotrapping spectra are demonstrated to depend on excitation wavelength. We also compare the femtosecond photodynamics in PYP at two excitation wavelengths (435 and 475 nm) with a dual-excitation-wavelength-interleaved pump-probe technique. Multicompartment global analysis of these data demonstrates that the excited-state photochemistry of PYP depends subtly, but convincingly, on excitation wavelength with similar kinetics with distinctly different spectral features, including a shifted ground-state beach and altered stimulated emission oscillator strengths and peak positions. Three models involving multiple excited states, vibrationally enhanced barrier crossing, and inhomogeneity are proposed to interpret the observed excitation-wavelength dependence of the data. Conformational heterogeneity was identified as the most probable model, which was supported with molecular mechanics simulations that identified two levels of inhomogeneity involving the orientation of the R52 residue and different hydrogen bonding networks with the p-coumaric acid chromophore. Quantum calculations were used to confirm that these inhomogeneities track to altered spectral properties consistent with the experimental results.
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Affiliation(s)
- L Tyler Mix
- Department of Chemistry , University of California, Davis , One Shields Avenue , Davis , California 95616 , United States
| | - Elizabeth C Carroll
- Department of Chemistry , University of California, Davis , One Shields Avenue , Davis , California 95616 , United States
| | - Dmitry Morozov
- Department of Chemistry and NanoScience Center , University of Jyväskylä , P.O. Box 35, 40014 Jyväskylä , Finland
| | - Jie Pan
- Department of Chemistry , University of California, Davis , One Shields Avenue , Davis , California 95616 , United States
| | | | | | - Jack Fuzell
- Department of Chemistry , University of California, Davis , One Shields Avenue , Davis , California 95616 , United States
| | - Masato Kumauchi
- Department of Microbiology and Molecular Genetics , Oklahoma State University , Stillwater , Oklahoma 74078 , United States
| | - Ivo van Stokkum
- Faculty of Sciences , Vrije Universiteit Amsterdam , De Boelelaan 1081 , 1081 HV Amsterdam , The Netherlands
| | - Gerrit Groenhof
- Department of Chemistry and NanoScience Center , University of Jyväskylä , P.O. Box 35, 40014 Jyväskylä , Finland
| | - Wouter D Hoff
- Department of Microbiology and Molecular Genetics , Oklahoma State University , Stillwater , Oklahoma 74078 , United States
| | - Delmar S Larsen
- Department of Chemistry , University of California, Davis , One Shields Avenue , Davis , California 95616 , United States
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Graen T, Inhester L, Clemens M, Grubmüller H, Groenhof G. The Low Barrier Hydrogen Bond in the Photoactive Yellow Protein: A Vacuum Artifact Absent in the Crystal and Solution. J Am Chem Soc 2016; 138:16620-16631. [PMID: 27966904 DOI: 10.1021/jacs.6b05609] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
There has been considerable debate on the existence of a low-barrier hydrogen bond (LBHB) in the photoactive yellow protein (PYP). The debate was initially triggered by the neutron diffraction study of Yamaguchi et al. ( Proc. Natl. Acad. Sci., U. S. A. , 2009 , 106 , 440 - 444 ) who suggested a model in which a neutral Arg52 residue triggers the formation of the LBHB in PYP. Here, we present an alternative model that is consistent within the error margins of the Yamaguchi structure factors. The model explains an increased hydrogen bond length without nuclear quantum effects and for a protonated Arg52. We tested both models by calculations under crystal, solution, and vacuum conditions. Contrary to the common assumption in the field, we found that a single PYP in vacuum does not provide an accurate description of the crystal conditions but instead introduces strong artifacts, which favor a LBHB and a large 1H NMR chemical shift. Our model of the crystal environment was found to stabilize the two Arg52 hydrogen bonds and crystal water positions for the protonated Arg52 residue in free MD simulations and predicted an Arg52 pKa upshift with respect to PYP in solution. The crystal and solution environments resulted in almost identical 1H chemical shifts that agree with NMR solution data. We also calculated the effect of the Arg52 protonation state on the LBHB in 3D nuclear equilibrium density calculations. Only the charged crystal structure in vacuum supports a LBHB if Arg52 is neutral in PYP at the previously reported level of theory ( J. Am. Chem. Soc. , 2014 , 136 , 3542 - 3552 ). We attribute the anomalies in the interpretation of the neutron data to a shift of the potential minimum, which does not involve nuclear quantum effects and is transferable beyond the Yamaguchi structure.
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Affiliation(s)
- Timo Graen
- Max Planck Institute for Biophysical Chemistry , Am Faßberg 11, 37077 Göttingen, Germany
| | - Ludger Inhester
- Center for Free-Electron Laser Science, DESY , Notkestrasse 85, 22607 Hamburg, Germany
| | - Maike Clemens
- Max Planck Institute for Biophysical Chemistry , Am Faßberg 11, 37077 Göttingen, Germany
| | - Helmut Grubmüller
- Max Planck Institute for Biophysical Chemistry , Am Faßberg 11, 37077 Göttingen, Germany
| | - Gerrit Groenhof
- Department of Chemistry and Nanoscience Center, University of Jyväskylä , P. O. Box 35, 40014 Jyväskylän Yliopisto, Finland
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9
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Structural investigation of ribonuclease A conformational preferences using high pressure protein crystallography. Chem Phys 2016. [DOI: 10.1016/j.chemphys.2016.01.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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10
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Tamura K, Hayashi S. Role of Bulk Water Environment in Regulation of Functional Hydrogen-Bond Network in Photoactive Yellow Protein. J Phys Chem B 2015; 119:15537-49. [DOI: 10.1021/acs.jpcb.5b07555] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Koichi Tamura
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Shigehiko Hayashi
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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11
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Gromov EV. Unveiling the mechanism of photoinduced isomerization of the photoactive yellow protein (PYP) chromophore. J Chem Phys 2014; 141:224308. [DOI: 10.1063/1.4903174] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Affiliation(s)
- Evgeniy V. Gromov
- Theoretische Chemie, Physikalisch-Chemisches Institut, Universität Heidelberg, Heidelberg, Germany
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12
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Zhu J, Vreede J, Hospes M, Arents J, Kennis JTM, van Stokkum IHM, Hellingwerf KJ, Groot ML. Short Hydrogen Bonds and Negative Charge in Photoactive Yellow Protein Promote Fast Isomerization but not High Quantum Yield. J Phys Chem B 2014; 119:2372-83. [DOI: 10.1021/jp506785q] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Jingyi Zhu
- Department
of Physics and Astronomy, Faculty of Sciences, LaserLab, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | | | | | | | - John T. M. Kennis
- Department
of Physics and Astronomy, Faculty of Sciences, LaserLab, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Ivo H. M. van Stokkum
- Department
of Physics and Astronomy, Faculty of Sciences, LaserLab, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | | | - Marie Louise Groot
- Department
of Physics and Astronomy, Faculty of Sciences, LaserLab, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
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13
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Gromov EV, Burghardt I, Köppel H, Cederbaum LS. Native hydrogen bonding network of the photoactive yellow protein (PYP) chromophore: Impact on the electronic structure and photoinduced isomerization. J Photochem Photobiol A Chem 2012. [DOI: 10.1016/j.jphotochem.2012.01.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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14
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Accessing protein conformational ensembles using room-temperature X-ray crystallography. Proc Natl Acad Sci U S A 2011; 108:16247-52. [PMID: 21918110 DOI: 10.1073/pnas.1111325108] [Citation(s) in RCA: 440] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Modern protein crystal structures are based nearly exclusively on X-ray data collected at cryogenic temperatures (generally 100 K). The cooling process is thought to introduce little bias in the functional interpretation of structural results, because cryogenic temperatures minimally perturb the overall protein backbone fold. In contrast, here we show that flash cooling biases previously hidden structural ensembles in protein crystals. By analyzing available data for 30 different proteins using new computational tools for electron-density sampling, model refinement, and molecular packing analysis, we found that crystal cryocooling remodels the conformational distributions of more than 35% of side chains and eliminates packing defects necessary for functional motions. In the signaling switch protein, H-Ras, an allosteric network consistent with fluctuations detected in solution by NMR was uncovered in the room-temperature, but not the cryogenic, electron-density maps. These results expose a bias in structural databases toward smaller, overpacked, and unrealistically unique models. Monitoring room-temperature conformational ensembles by X-ray crystallography can reveal motions crucial for catalysis, ligand binding, and allosteric regulation.
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Rupenyan AB, Vreede J, van Stokkum IHM, Hospes M, Kennis JTM, Hellingwerf KJ, Groot ML. Proline 68 enhances photoisomerization yield in photoactive yellow protein. J Phys Chem B 2011; 115:6668-77. [PMID: 21542640 DOI: 10.1021/jp112113s] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
In proteins and enzymes, the local environment of an active cofactor plays an important role in controlling the outcome of a functional reaction. In photoactive yellow protein (PYP), it ensures photoisomerization of the chromophore, a prerequisite for formation of a signaling state. PYP is the prototype of a PAS domain, and the preferred model system for the studies of molecular mechanisms of biological light sensing. We investigated the effect of replacing proline-68, positioned near but not in direct contact with the chromophore, with other neutral amino acids (alanine, glycine, and valine), using ultrafast spectroscopy probing the visible and the mid-IR spectral regions, and molecular simulation to understand the interactions tuning the efficiency of light signaling. Transient absorption measurements indicate that the quantum yield of isomerization in the mutants is lower than the yield observed for the wild type. Subpicosecond mid-IR spectra and molecular dynamics simulations of the four proteins reveal that the hydrogen bond interactions around the chromophore and the access of water molecules in the active site of the protein determine the efficiency of photoisomerization. The mutants provide additional hydrogen bonds to the chromophore, directly and by allowing more water molecules access to its binding pocket. We conclude that proline-68 in the wild type protein optimizes the yield of photochemistry by maintaining a weak hydrogen bond with the chromophore, at the same time restraining the entrance of water molecules close to the alkylic part of pCa. This study provides a molecular basis for the structural optimization of biological light sensing.
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Affiliation(s)
- Alisa B Rupenyan
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, Amsterdam, The Netherlands.
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Krishnan R, Walton EB, Van Vliet KJ. Characterizing rare-event property distributions via replicate molecular dynamics simulations of proteins. J Mol Model 2009; 15:1383-9. [PMID: 19418077 DOI: 10.1007/s00894-009-0504-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2009] [Accepted: 03/09/2009] [Indexed: 11/26/2022]
Abstract
As computational resources increase, molecular dynamics simulations of biomolecules are becoming an increasingly informative complement to experimental studies. In particular, it has now become feasible to use multiple initial molecular configurations to generate an ensemble of replicate production-run simulations that allows for more complete characterization of rare events such as ligand-receptor unbinding. However, there are currently no explicit guidelines for selecting an ensemble of initial configurations for replicate simulations. Here, we use clustering analysis and steered molecular dynamics simulations to demonstrate that the configurational changes accessible in molecular dynamics simulations of biomolecules do not necessarily correlate with observed rare-event properties. This informs selection of a representative set of initial configurations. We also employ statistical analysis to identify the minimum number of replicate simulations required to sufficiently sample a given biomolecular property distribution. Together, these results suggest a general procedure for generating an ensemble of replicate simulations that will maximize accurate characterization of rare-event property distributions in biomolecules.
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Affiliation(s)
- Ranjani Krishnan
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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17
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Bourgeois D, Weik M. Kinetic protein crystallography: a tool to watch proteins in action. CRYSTALLOGR REV 2009. [DOI: 10.1080/08893110802604868] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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