Waterless structures in the Protein Data Bank
[ 1 ] Instytut Informatyki, Wydział Informatyki i Telekomunikacji, Politechnika Poznańska | [ P ] employee
2024
scientific article
english
- protein hydration
- structure-factor statistics
- structure-quality statistics
- modeling errors
- electron density
- Protein Data Bank
- PDB-REDO
- protein structure
- X-ray crystallography
EN The absence of solvent molecules in high-resolution protein crystal structure models deposited in the Protein Data Bank (PDB) contradicts the fact that, for proteins crystallized from aqueous media, water molecules are always expected to bind to the protein surface, as well as to some sites in the protein interior. An analysis of the contents of the PDB indicated that the expected ratio of the number of water molecules to the number of amino-acid residues exceeds 1.5 in atomic resolution structures, decreasing to 0.25 at around 2.5 A˚ resolution. Nevertheless, almost 800 protein crystal structures determined at a resolution of 2.5 A˚ or higher are found in the current release of the PDB without any water molecules, whereas some other depositions have unusually low or high occupancies of modeled solvent. Detailed analysis of these depositions revealed that the lack of solvent molecules might be an indication of problems with either the diffraction data, the refinement protocol, the deposition process or a combination of these factors. It is postulated that problems with solvent structure should be flagged by the PDB and addressed by the depositors.
966 - 976
CC BY (attribution alone)
open journal
final published version
at the time of publication
140
2,9 [List 2023]