ISSN:
1399-0047
Source:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
Notes:
A detailed analysis of the occurrence of the C—H...O hydrogen bonds in sheet regions of proteins has been presented. 11 unique protein structures with resolution 1.3 Å containing β-sheets show a widespread presence of C—H...O hydrogen bonds. These have average Cα...O, CH...O distances and a Cα—H...O angle of 3.29, 2.38 Å and 143°, respectively. As in the case of N—H...O hydrogen bonds, parallel and antiparallel β-sheet regions show the same hydrogen-bond geometry. An inverse correlation is observed between the hydrogen-bond geometries involving the Cαi—H...O=C and the Ni+1—H...O=C suggesting that C—H...O hydrogen bonds may act as an additional stabilizing factor. The propensity of different amino-acid residues to form such hydrogen bonds varies and shows a clear preference for valine and threonine. C—H...O hydrogen bonds involving side chains also occur extensively in β-sheet regions.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1107/S0907444997000383
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