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Updated: Jan 30, 2026
Crystallizing Membrane Proteins for Structure Determination using Lipidic Mesophases
Published on: November 21, 2010
Crystal Structure of Photosystem I Monomer From Synechocystis PCC 6803
Sigal Yoli Netzer-El1, Ido Caspy1, Nathan Nelson1
1Department of Biochemistry and Molecular Biology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.
Abstract:
A single histidine addition to the C-terminus of PsaL of Synechocystis sp. PCC 6803 was previously reported by our lab to shift the trimer-to-monomer ratio of PSI in favor of the monomeric form. P700 re-reduction and NADP+ photo-reduction measurements of the PsaLHIS strain show no effect on PSI activity in comparison to the WT trimeric PSI. Crystal structure of the PsaLHIS monomeric PSI reveals several alterations that occurred in the trimerisation site of PSI, primarily a deformation of the C-terminus of PsaL and loss of chlorophyll a and β-carotene molecules.
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