Open AccessSpatial distribution of radiation damage to crystalline proteins at 25–300 K
Author(s) -
Warkentin Matthew,
Badeau Ryan,
Hopkins Jesse B.,
Thorne Robert E.
Publication year - 2012
Publication title -
acta crystallographica section d
Language(s) - English
Resource type - Journals
ISSN - 1399-0047
DOI - 10.1107/s0907444912021361
Subject(s) - mosaicity , radiation damage , solvent , crystallography , crystal (programming language) , chemistry , radiation , chemical physics , thaumatin , crystal structure , spatial distribution , lattice (music) , materials science , molecular physics , optics , physics , x ray crystallography , diffraction , biochemistry , mathematics , statistics , computer science , acoustics , gene , programming language
The spatial distribution of radiation damage (assayed by increases in atomic B factors) to thaumatin and urease crystals at temperatures ranging from 25 to 300 K is reported. The nature of the damage changes dramatically at approximately 180 K. Above this temperature the role of solvent diffusion is apparent in thaumatin crystals, as solvent‐exposed turns and loops are especially sensitive. In urease, a flap covering the active site is the most sensitive part of the molecule and nearby loops show enhanced sensitivity. Below 180 K sensitivity is correlated with poor local packing, especially in thaumatin. At all temperatures, the component of the damage that is spatially uniform within the unit cell accounts for more than half of the total increase in the atomic B factors and correlates with changes in mosaicity. This component may arise from lattice‐level, rather than local, disorder. The effects of primary structure on radiation sensitivity are small compared with those of tertiary structure, local packing, solvent accessibility and crystal contacts.