Abstract
Gloeobacter violaceus PCC 7421 is a thylakoid-lacking unicellular cyanobacterium. In its complete genome sequence, however, we found a gene (glr0898) homologous to vipp1 (vesicle-inducing protein in plastids 1) that is known to be essential for thylakoid membrane formation in other cyanobacteria and chloroplasts [1]. Amino acid sequence of Glr0898 was also similar to that of phage shock protein A (PspA) that is not involved in thylakoid membrane formation. To investigate the function of glr0898 gene in vivo, we introduced a glr0898 gene into Synechocystis sp. PCC 6803 cells, and subsequently knocked-out the endogenous vipp1 genes of the glr0898-expressing transformants. These transformant cells showed that growth rates, absorption spectra and chlorophyll contents were nearly identical to those of wild type cells. These results suggested that the glr0898 complemented the loss of Synechocystis vipp1 in the transformant cells.
[1] Westphal et al. (2001) Proc. Natl. Acad. Sci. USA, 98, 4243.