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Neutron Crystallography Data Collection and Processing for Modelling Hydrogen Atoms in Protein Structures
Published on: December 1, 2020
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Conformation-dependent backbone geometry restraints set a new standard for protein crystallographic refinement
Nigel W Moriarty1, Dale E Tronrud, Paul D Adams
1Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
The FEBS Journal
|June 4, 2014
Summary
A new conformation-dependent library (CDL) for protein backbone restraints improves structural model accuracy. This CDL, implemented in the phenix package, enhances agreement with ideal bond angles and lengths without drawbacks.
Area of Science:
- Structural biology
- Biophysics
- Computational biology
Background:
- Protein crystal structure refinement relies on ideal bond angles and lengths as restraints.
- Current restraints assume context-independent ideal values, which is an oversimplification.
- Local conformation influences ideal geometric parameters in proteins.
Purpose of the Study:
- To introduce a conformation-dependent library (CDL) for protein backbone restraints into the phenix software package.
- To evaluate the impact of the CDL on the refinement of protein crystal structures.
- To improve the accuracy of protein structural models by incorporating context-dependent geometry.
Main Methods:
- Derivation of a CDL using ultra-high-resolution protein crystal structures.
- Implementation of the CDL within the phenix refinement package.
- Testing the CDL through refinement of thousands of protein structures across various resolutions.
Main Results:
- Use of the CDL significantly improves agreement with ideal main-chain bond angles and lengths.
- Models refined with the CDL show a slight enhancement in fitting X-ray diffraction data.
- No disadvantages were observed when applying the backbone CDL.
Conclusions:
- The conformation-dependent library (CDL) is effectively integrated into phenix, enabling context-aware restraints.
- The CDL enhances the accuracy of protein structural models, particularly regarding main-chain geometry.
- This work provides a foundation for further characterization and application of context-dependent geometry in structural biology.
Keywords:
crystallographic refinementgeometry restraintsideal geometryprotein structurestructural genomicsMore Related Videos
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