Evidence map›Paper›PMID 31909743›Full record

ArticleActa crystallographica. Section D, Structural biology2020

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

Nigel W Moriarty, Pawel A Janowski, Jason M Swails, Hai Nguyen, Jane S Richardson, David A Case, Paul D Adams

Open access · hybridAbstract read
In one paragraph

Article in Acta crystallographica. Section D, Structural biology, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 31 papers.

0numbers the graph read from it
0cells of the map it votes in
31citing papers in PubMed
1.9field-weighted citation impact, top 14% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

31 citing papers in PubMed, 43 citations in OpenAlex.

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  10. If you cannot see it, is it still there?Journal of applied crystallography · 2025
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  11. SFCalculator: connecting deep generative models and crystallography.bioRxiv : the preprint server for biology · 2025
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  15. In situ ligand restraints from quantum-mechanical methods.Acta crystallographica. Section D, Structural biology · 2023
    Article
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors at 3 institutions in 1 country.

Nigel W MoriartyMolecular Biosciences and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720-8235, USA.ORCID 0000-0001-8857-9464
Pawel A JanowskiDepartment of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA.
Jason M SwailsDepartment of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA.
Hai NguyenDepartment of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA.
Jane S RichardsonDepartment of Biochemistry, Duke University, Durham, NC 27710, USA.ORCID 0000-0002-3311-2944
David A CaseDepartment of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA.ORCID 0000-0003-2314-2346
Paul D AdamsMolecular Biosciences and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720-8235, USA.ORCID 0000-0001-9333-8219
Rutgers, The State University of New Jersey · USLawrence Berkeley National Laboratory · USDuke University · US

Funding

PROJECT 5 - DUKE - STRUCTURE VALIDATION AND IMPROVEMENT FOR PROTEINS AND N. ACIDSP01GM063210 · NIGMS · UNIVERSITY OF CALIF-LAWRENC BERKELEY LAB · PI ADAMS, PAUL DAVID · 2001 to 2021
$33.5M
Combining molecular dynamics simulations with crystallographic refinementR01GM122086 · NIGMS · RUTGERS, THE STATE UNIV OF N.J. · PI CASE, DAVID A · 2017 to 2020
$1.1M
Department of Energy DE-AC02-05CH11231NIGMS NIH HHS P01 GM063210NIGMS NIH HHS R01 GM122086NIH HHS GM122086NIH HHS P01GM063210
6 · The paper itself

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 more advanced applications such as Amber-based ensemble refinement, quantum-mechanical representation of active sites and improved geometric restraints for simulated annealing.

Indexed as

SoftwareCryoelectron MicroscopyCrystallography, X-RayDatabases, ProteinHydrogen BondingMolecular Dynamics SimulationProtein ConformationProteinsProteinsAmber in PhenixAmber refinement targetCβ deviationshydrogen-bond qualitypeptide orientations

Identifiers

PMID31909743
PMCPMC6939439
OpenAlexW2996209820

What OpenQuestion holds

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Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.