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Updated: Aug 22, 2026
ABCG5/G8 Crystallization in a Lipidic Bicelle Environment for X-Ray Crystallography
Published on: August 25, 2023
Physical detwinning of hemihedrally twinned hexagonal crystals of bacteriorhodopsin
Rouslan Efremov1, Rouslan Moukhametzianov, Georg Büldt
1Institute for Structural Biology (IBI-2), Forschungszentrum Jülich, D-52425 Jülich, Germany.
Abstract:
Hexagonal crystals of the membrane protein bacteriorhodopsin of space group P6 3 grown in lipidic cubic phase are twinned hemihedrally. It was shown that slow changes of salt concentration in the mother liquor lead to a split of crystals so that the split parts preserved high diffraction quality. Analysis of diffraction data from split crystals by Yeates statistic and Britton plot showed that the split parts are free of twinning. It is concluded that crystals of bacteriorhodopsin are composed of several macroscopic twinning domains with sizes comparable to the original crystal. The appearance of twinning domains during crystal growth and the mechanism of splitting are discussed.
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