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Title: Improved chemistry restraints for crystallographic refinement by integrating the Amber force field into Phenix

Abstract

The refinement of biomolecular crystallographic models relies on geometric restraints to help to address the paucity of experimental data typical in these experiments. Limitations in these restraints can degrade the quality of the resulting atomic models. Here, an integration of the full all-atom Amber molecular-dynamics force field into Phenix crystallographic refinement is presented, which enables more complete modeling of biomolecular chemistry. The advantages of the force field include a carefully derived set of torsion-angle potentials, an extensive and flexible set of atom types, Lennard–Jones treatment of nonbonded interactions and a full treatment of crystalline electrostatics. The new combined method was tested against conventional geometry restraints for over 22 000 protein structures. Structures refined with the new method show substantially improved model quality. On average, Ramachandran and rotamer scores are somewhat better, clashscores and MolProbity scores are significantly improved, and the modeling of electrostatics leads to structures that exhibit more, and more correct, hydrogen bonds than those refined using traditional geometry restraints. In general it is found that model improvements are greatest at lower resolutions, prompting plans to add the Amber target function to real-space refinement for use in electron cryo-microscopy. This work opens the door to the future development of moremore » advanced applications such as Amber -based ensemble refinement, quantum-mechanical representation of active sites and improved geometric restraints for simulated annealing.« less

Authors:
ORCiD logo; ; ; ; ORCiD logo; ORCiD logo; ORCiD logo
Publication Date:
Research Org.:
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC); National Institutes of Health (NIH); Phenix Industrial Consortium
OSTI Identifier:
1617952
Alternate Identifier(s):
OSTI ID: 1599830
Grant/Contract Number:  
AC02-05CH11231; GM122086; P01GM063210
Resource Type:
Published Article
Journal Name:
Acta Crystallographica. Section D. Structural Biology
Additional Journal Information:
Journal Name: Acta Crystallographica. Section D. Structural Biology Journal Volume: 76 Journal Issue: 1; Journal ID: ISSN 2059-7983
Publisher:
International Union of Crystallography (IUCr)
Country of Publication:
United Kingdom
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; Amber refinement target; hydrogen-bond quality; Amber in Phenix; Cβ deviations; peptide orientations

Citation Formats

Moriarty, Nigel W., Janowski, Pawel A., Swails, Jason M., Nguyen, Hai, Richardson, Jane S., Case, David A., and Adams, Paul D. Improved chemistry restraints for crystallographic refinement by integrating the Amber force field into Phenix. United Kingdom: N. p., 2020. Web. doi:10.1107/S2059798319015134.
Moriarty, Nigel W., Janowski, Pawel A., Swails, Jason M., Nguyen, Hai, Richardson, Jane S., Case, David A., & Adams, Paul D. Improved chemistry restraints for crystallographic refinement by integrating the Amber force field into Phenix. United Kingdom. https://doi.org/10.1107/S2059798319015134
Moriarty, Nigel W., Janowski, Pawel A., Swails, Jason M., Nguyen, Hai, Richardson, Jane S., Case, David A., and Adams, Paul D. Wed . "Improved chemistry restraints for crystallographic refinement by integrating the Amber force field into Phenix". United Kingdom. https://doi.org/10.1107/S2059798319015134.
@article{osti_1617952,
title = {Improved chemistry restraints for crystallographic refinement by integrating the Amber force field into Phenix},
author = {Moriarty, Nigel W. and Janowski, Pawel A. and Swails, Jason M. and Nguyen, Hai and Richardson, Jane S. and Case, David A. and Adams, Paul D.},
abstractNote = {The refinement of biomolecular crystallographic models relies on geometric restraints to help to address the paucity of experimental data typical in these experiments. Limitations in these restraints can degrade the quality of the resulting atomic models. Here, an integration of the full all-atom Amber molecular-dynamics force field into Phenix crystallographic refinement is presented, which enables more complete modeling of biomolecular chemistry. The advantages of the force field include a carefully derived set of torsion-angle potentials, an extensive and flexible set of atom types, Lennard–Jones treatment of nonbonded interactions and a full treatment of crystalline electrostatics. The new combined method was tested against conventional geometry restraints for over 22 000 protein structures. Structures refined with the new method show substantially improved model quality. On average, Ramachandran and rotamer scores are somewhat better, clashscores and MolProbity scores are significantly improved, and the modeling of electrostatics leads to structures that exhibit more, and more correct, hydrogen bonds than those refined using traditional geometry restraints. In general it is found that model improvements are greatest at lower resolutions, prompting plans to add the Amber target function to real-space refinement for use in electron cryo-microscopy. This work opens the door to the future development of more advanced applications such as Amber -based ensemble refinement, quantum-mechanical representation of active sites and improved geometric restraints for simulated annealing.},
doi = {10.1107/S2059798319015134},
journal = {Acta Crystallographica. Section D. Structural Biology},
number = 1,
volume = 76,
place = {United Kingdom},
year = {Wed Jan 01 00:00:00 EST 2020},
month = {Wed Jan 01 00:00:00 EST 2020}
}

Journal Article:
Free Publicly Available Full Text
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https://doi.org/10.1107/S2059798319015134

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Works referenced in this record:

Validation of Molecular Dynamics Simulations of Biomolecules Using NMR Spin Relaxation as Benchmarks:  Application to the AMBER99SB Force Field
journal, March 2007

  • Showalter, Scott A.; Brüschweiler, Rafael
  • Journal of Chemical Theory and Computation, Vol. 3, Issue 3
  • DOI: 10.1021/ct7000045

New parameters for the refinement of nucleic acid-containing structures
journal, January 1996

  • Parkinson, G.; Vojtechovsky, J.; Clowney, L.
  • Acta Crystallographica Section D Biological Crystallography, Vol. 52, Issue 1
  • DOI: 10.1107/S0907444995011115

Refinement of Macromolecular Structures by the Maximum-Likelihood Method
journal, May 1997

  • Murshudov, G. N.; Vagin, A. A.; Dodson, E. J.
  • Acta Crystallographica Section D Biological Crystallography, Vol. 53, Issue 3
  • DOI: 10.1107/S0907444996012255

Molprobity's ultimate rotamer-library distributions for model validation: MolProbity's Ultimate Rotamer-Library
journal, June 2016

  • Hintze, Bradley J.; Lewis, Steven M.; Richardson, Jane S.
  • Proteins: Structure, Function, and Bioinformatics, Vol. 84, Issue 9
  • DOI: 10.1002/prot.25039

Least-squares refinement with subsidiary conditions
journal, November 1963


Dynamics of the Streptavidin−Biotin Complex in Solution and in Its Crystal Lattice: Distinct Behavior Revealed by Molecular Simulations
journal, May 2009

  • Cerutti, David S.; Trong, Isolde Le; Stenkamp, Ronald E.
  • The Journal of Physical Chemistry B, Vol. 113, Issue 19
  • DOI: 10.1021/jp9010372

The Cambridge Structural Database
journal, April 2016

  • Groom, Colin R.; Bruno, Ian J.; Lightfoot, Matthew P.
  • Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials, Vol. 72, Issue 2, p. 171-179
  • DOI: 10.1107/S2052520616003954

Is one solution good enough?
journal, March 2006

  • Furnham, Nicholas; Blundell, Tom L.; DePristo, Mark A.
  • Nature Structural & Molecular Biology, Vol. 13, Issue 3
  • DOI: 10.1038/nsmb0306-184

Integrative, dynamic structural biology at atomic resolution—it's about time
journal, March 2015

  • van den Bedem, Henry; Fraser, James S.
  • Nature Methods, Vol. 12, Issue 4
  • DOI: 10.1038/nmeth.3324

Atomistic Folding Simulations of the Five-Helix Bundle Protein λ 6−85
journal, February 2011

  • Bowman, Gregory R.; Voelz, Vincent A.; Pande, Vijay S.
  • Journal of the American Chemical Society, Vol. 133, Issue 4
  • DOI: 10.1021/ja106936n

Automatic atom type and bond type perception in molecular mechanical calculations
journal, October 2006

  • Wang, Junmei; Wang, Wei; Kollman, Peter A.
  • Journal of Molecular Graphics and Modelling, Vol. 25, Issue 2
  • DOI: 10.1016/j.jmgm.2005.12.005

MolProbity: More and better reference data for improved all-atom structure validation: PROTEIN SCIENCE.ORG
journal, November 2017

  • Williams, Christopher J.; Headd, Jeffrey J.; Moriarty, Nigel W.
  • Protein Science, Vol. 27, Issue 1
  • DOI: 10.1002/pro.3330

A new default restraint library for the protein backbone in Phenix : a conformation-dependent geometry goes mainstream
journal, January 2016

  • Moriarty, Nigel W.; Tronrud, Dale E.; Adams, Paul D.
  • Acta Crystallographica Section D Structural Biology, Vol. 72, Issue 1
  • DOI: 10.1107/S2059798315022408

Using a conformation-dependent stereochemical library improves crystallographic refinement of proteins
journal, June 2010

  • Tronrud, Dale E.; Berkholz, Donald S.; Karplus, P. Andrew
  • Acta Crystallographica Section D Biological Crystallography, Vol. 66, Issue 7
  • DOI: 10.1107/S0907444910019207

Towards automated crystallographic structure refinement with phenix.refine
journal, March 2012

  • Afonine, Pavel V.; Grosse-Kunstleve, Ralf W.; Echols, Nathaniel
  • Acta Crystallographica Section D Biological Crystallography, Vol. 68, Issue 4
  • DOI: 10.1107/S0907444912001308

An efficient general-purpose least-squares refinement program for macromolecular structures
journal, July 1987

  • Tronrud, D. E.; Ten Eyck, L. F.; Matthews, B. W.
  • Acta Crystallographica Section A Foundations of Crystallography, Vol. 43, Issue 4
  • DOI: 10.1107/S0108767387099124

Molecular simulation as an aid to experimentalists
journal, April 2008

  • van Gunsteren, Wilfred F.; Dolenc, Jožica; Mark, Alan E.
  • Current Opinion in Structural Biology, Vol. 18, Issue 2
  • DOI: 10.1016/j.sbi.2007.12.007

Macromolecular structure determination using X-rays, neutrons and electrons: recent developments in Phenix
journal, October 2019

  • Liebschner, Dorothee; Afonine, Pavel V.; Baker, Matthew L.
  • Acta Crystallographica Section D Structural Biology, Vol. 75, Issue 10
  • DOI: 10.1107/S2059798319011471

Comparison of simple potential functions for simulating liquid water
journal, July 1983

  • Jorgensen, William L.; Chandrasekhar, Jayaraman; Madura, Jeffry D.
  • The Journal of Chemical Physics, Vol. 79, Issue 2
  • DOI: 10.1063/1.445869

Refinement of large structures by simultaneous minimization of energy and R factor
journal, November 1978


Molecular Dynamics Simulations of the Dynamic and Energetic Properties of Alkali and Halide Ions Using Water-Model-Specific Ion Parameters
journal, October 2009

  • Joung, In Suk; Cheatham, Thomas E.
  • The Journal of Physical Chemistry B, Vol. 113, Issue 40
  • DOI: 10.1021/jp902584c

Reintroducing electrostatics into protein X-ray structure refinement: bulk solvent treated as a dielectric continuum
journal, November 2003

  • Moulinier, Luc; Case, David A.; Simonson, Thomas
  • Acta Crystallographica Section D Biological Crystallography, Vol. 59, Issue 12
  • DOI: 10.1107/S090744490301833X

electronic Ligand Builder and Optimization Workbench ( eLBOW ): a tool for ligand coordinate and restraint generation
journal, September 2009

  • Moriarty, Nigel W.; Grosse-Kunstleve, Ralf W.; Adams, Paul D.
  • Acta Crystallographica Section D Biological Crystallography, Vol. 65, Issue 10
  • DOI: 10.1107/S0907444909029436

The Backrub Motion: How Protein Backbone Shrugs When a Sidechain Dances
journal, February 2006


Development and testing of a general amber force field
journal, January 2004

  • Wang, Junmei; Wolf, Romain M.; Caldwell, James W.
  • Journal of Computational Chemistry, Vol. 25, Issue 9
  • DOI: 10.1002/jcc.20035

Asparagine and glutamine: using hydrogen atom contacts in the choice of side-chain amide orientation 1 1Edited by J. Thornton
journal, January 1999

  • Word, J. Michael; Lovell, Simon C.; Richardson, Jane S.
  • Journal of Molecular Biology, Vol. 285, Issue 4
  • DOI: 10.1006/jmbi.1998.2401

Modelling dynamics in protein crystal structures by ensemble refinement
journal, December 2012


Large-scale molecular dynamics simulation of DNA: implementation and validation of the AMBER98 force field in LAMMPS
journal, July 2004

  • Grindon, Christina; Harris, Sarah; Evans, Tom
  • Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, Vol. 362, Issue 1820
  • DOI: 10.1098/rsta.2004.1381

Visualizing and quantifying molecular goodness-of-fit: small-probe contact dots with explicit hydrogen atoms 1 1Edited by J. Thornton
journal, January 1999

  • Word, J. Michael; Lovell, Simon C.; LaBean, Thomas H.
  • Journal of Molecular Biology, Vol. 285, Issue 4
  • DOI: 10.1006/jmbi.1998.2400

Structure and dynamics of two β-peptides in solution from molecular dynamics simulations validated against experiment
journal, March 2008

  • Zagrovic, Bojan; Gattin, Zrinka; Lau, Justin Kai-Chi
  • European Biophysics Journal, Vol. 37, Issue 6
  • DOI: 10.1007/s00249-008-0307-y

Accurate bond and angle parameters for X-ray protein structure refinement
journal, July 1991

  • Engh, R. A.; Huber, R.
  • Acta Crystallographica Section A Foundations of Crystallography, Vol. 47, Issue 4
  • DOI: 10.1107/S0108767391001071

Polarizable atomic multipole X-ray refinement: application to peptide crystals
journal, August 2009

  • Schnieders, Michael J.; Fenn, Timothy D.; Pande, Vijay S.
  • Acta Crystallographica Section D Biological Crystallography, Vol. 65, Issue 9
  • DOI: 10.1107/S0907444909022707

Crystallographic refinement by simulated annealing: application to crambin
journal, January 1989

  • Brünger, A. T.; Karplus, M.; Petsko, G. A.
  • Acta Crystallographica Section A Foundations of Crystallography, Vol. 45, Issue 1
  • DOI: 10.1107/S0108767388009195

Particle mesh Ewald: An N ⋅log( N ) method for Ewald sums in large systems
journal, June 1993

  • Darden, Tom; York, Darrin; Pedersen, Lee
  • The Journal of Chemical Physics, Vol. 98, Issue 12
  • DOI: 10.1063/1.464397

All-atom crystal simulations of DNA and RNA duplexes
journal, May 2015

  • Liu, Chunmei; Janowski, Pawel A.; Case, David A.
  • Biochimica et Biophysica Acta (BBA) - General Subjects, Vol. 1850, Issue 5
  • DOI: 10.1016/j.bbagen.2014.09.018

Conformation-dependent backbone geometry restraints set a new standard for protein crystallographic refinement
journal, June 2014

  • Moriarty, Nigel W.; Tronrud, Dale E.; Adams, Paul D.
  • FEBS Journal, Vol. 281, Issue 18
  • DOI: 10.1111/febs.12860

RCSB Protein Data Bank: biological macromolecular structures enabling research and education in fundamental biology, biomedicine, biotechnology and energy
journal, October 2018

  • Burley, Stephen K.; Berman, Helen M.; Bhikadiya, Charmi
  • Nucleic Acids Research, Vol. 47, Issue D1
  • DOI: 10.1093/nar/gky1004

ff14SB: Improving the Accuracy of Protein Side Chain and Backbone Parameters from ff99SB
journal, July 2015

  • Maier, James A.; Martinez, Carmenza; Kasavajhala, Koushik
  • Journal of Chemical Theory and Computation, Vol. 11, Issue 8
  • DOI: 10.1021/acs.jctc.5b00255

Crystallographic R Factor Refinement by Molecular Dynamics
journal, January 1987


Application and Limitations of X-ray Crystallographic Data in Structure-Based Ligand and Drug Design
journal, June 2003

  • Davis, Andrew M.; Teague, Simon J.; Kleywegt, Gerard J.
  • Angewandte Chemie International Edition, Vol. 42, Issue 24
  • DOI: 10.1002/anie.200200539

Simulations of a Protein Crystal: Explicit Treatment of Crystallization Conditions Links Theory and Experiment in the Streptavidin−Biotin Complex
journal, November 2008

  • Cerutti, David S.; Le Trong, Isolde; Stenkamp, Ronald E.
  • Biochemistry, Vol. 47, Issue 46
  • DOI: 10.1021/bi800894u

REFMAC 5 for the refinement of macromolecular crystal structures
journal, March 2011

  • Murshudov, Garib N.; Skubák, Pavol; Lebedev, Andrey A.
  • Acta Crystallographica Section D Biological Crystallography, Vol. 67, Issue 4
  • DOI: 10.1107/S0907444911001314

Use of Locally Enhanced Sampling in Free Energy Calculations:  Testing and Application to the α → β Anomerization of Glucose
journal, June 1998

  • Simmerling, Carlos; Fox, Thomas; Kollman, Peter A.
  • Journal of the American Chemical Society, Vol. 120, Issue 23
  • DOI: 10.1021/ja972457n

Peptide Crystal Simulations Reveal Hidden Dynamics
journal, May 2013

  • Janowski, Pawel A.; Cerutti, David S.; Holton, James
  • Journal of the American Chemical Society, Vol. 135, Issue 21
  • DOI: 10.1021/ja401382y

Structure validation by Cα geometry: ϕ,ψ and Cβ deviation
journal, January 2003

  • Lovell, Simon C.; Davis, Ian W.; Arendall, W. Bryan
  • Proteins: Structure, Function, and Bioinformatics, Vol. 50, Issue 3
  • DOI: 10.1002/prot.10286

Assessment of detailed conformations suggests strategies for improving cryoEM models: Helix at lower resolution, ensembles, pre-refinement fixups, and validation at multi-residue length scale
journal, November 2018

  • Richardson, Jane S.; Williams, Christopher J.; Videau, Lizbeth L.
  • Journal of Structural Biology, Vol. 204, Issue 2
  • DOI: 10.1016/j.jsb.2018.08.007

Crystal structure refinement with SHELXL
journal, January 2015

  • Sheldrick, George M.
  • Acta Crystallographica Section C Structural Chemistry, Vol. 71, Issue 1, p. 3-8
  • DOI: 10.1107/S2053229614024218

R free and the R free ratio. II. Calculation of the expected values and variances of cross-validation statistics in macromolecular least-squares refinement
journal, April 2000

  • Tickle, Ian J.; Laskowski, Roman A.; Moss, David S.
  • Acta Crystallographica Section D Biological Crystallography, Vol. 56, Issue 4
  • DOI: 10.1107/S0907444999016868

PHENIX: a comprehensive Python-based system for macromolecular structure solution
journal, January 2010

  • Adams, Paul D.; Afonine, Pavel V.; Bunkóczi, Gábor
  • Acta Crystallographica Section D Biological Crystallography, Vol. 66, Issue 2, p. 213-221
  • DOI: 10.1107/S0907444909052925

Diffuse X-Ray Scattering to Model Protein Motions
journal, February 2014


KING (Kinemage, Next Generation): A versatile interactive molecular and scientific visualization program
journal, November 2009

  • Chen, Vincent B.; Davis, Ian W.; Richardson, David C.
  • Protein Science, Vol. 18, Issue 11
  • DOI: 10.1002/pro.250

The Protein Data Bank
journal, January 2000


Molecular dynamics simulations with experimental restraints
journal, February 1991

  • Bruenger, Axel T.; Karplus, Martin
  • Accounts of Chemical Research, Vol. 24, Issue 2
  • DOI: 10.1021/ar00002a005

Molecular dynamics simulation of triclinic lysozyme in a crystal lattice: Molecular Dynamics of Crystal Lysozyme
journal, June 2015

  • Janowski, Pawel A.; Liu, Chunmei; Deckman, Jason
  • Protein Science, Vol. 25, Issue 1
  • DOI: 10.1002/pro.2713

On the complexity of Engh and Huber refinement restraints: the angle τ as example
journal, November 2010

  • Touw, Wouter G.; Vriend, Gert
  • Acta Crystallographica Section D Biological Crystallography, Vol. 66, Issue 12
  • DOI: 10.1107/S0907444910040928

Crystal structure of methionine aminopeptidase from hyperthermophile, Pyrococcus furiosus a 1Edited by R. Huber
journal, November 1998

  • Tahirov, Tahir H.; Oki, Hideyuki; Tsukihara, Tomitake
  • Journal of Molecular Biology, Vol. 284, Issue 1
  • DOI: 10.1006/jmbi.1998.2146

Improved dihedral-angle restraints for protein structure refinement
journal, January 2003


PTRAJ and CPPTRAJ: Software for Processing and Analysis of Molecular Dynamics Trajectory Data
journal, June 2013

  • Roe, Daniel R.; Cheatham, Thomas E.
  • Journal of Chemical Theory and Computation, Vol. 9, Issue 7
  • DOI: 10.1021/ct400341p

Cross-validated maximum likelihood enhances crystallographic simulated annealing refinement
journal, May 1997

  • Adams, P. D.; Pannu, N. S.; Read, R. J.
  • Proceedings of the National Academy of Sciences, Vol. 94, Issue 10
  • DOI: 10.1073/pnas.94.10.5018

The effect of long‐range electrostatic interactions in simulations of macromolecular crystals: A comparison of the Ewald and truncated list methods
journal, November 1993

  • York, Darrin M.; Darden, Tom A.; Pedersen, Lee G.
  • The Journal of Chemical Physics, Vol. 99, Issue 10
  • DOI: 10.1063/1.465608