Abstract
The gene ycf33 exists in all the cyanobacterial and chloroplast genomes so far sequenced except green lineages, and is also found in the nuclear genome of A. thaliana. We have constructed a deletion mutant of ycf33 in Synechocystis sp. PCC6803 and have characterised the mutant.
It was indicated that the sensitivity of inhibitors to cyclic electron transport was different from wild type and the mutant. When the cells were grown under low light (30 μE/m2•s), the activity was less inhibited by HgCl2 in the wild type and far less inhibited in the mutant. On the other hand, the mutant was more sensitive to DPI, an inhibitor of flavoprotein. It was assumed that the pathway of cyclic electron transport is controled by FNR bound to thylakoid membranes. The amount of FNR was estimated by activity staining after native PAGE.
