Poster: Photosynthesis (light)

Abs # 220: Targeted Inactivation of FtsH Genes in Synechocystis sp. PCC 6803

Presenter:	Bailey, Dondra S, dondra@iastate.edu
Authors	Bailey, Dondra S (A)   Yu, Fei  (A)   Rodermel, Steven  (A)
Affiliations:	(A): Iowa State University

FtsH (filamentous temperature sensitive) genes are members of the AAA (ATPases associated with diverse cellular activities) class of proteases and contain an essential AAA domain, which contains the ATP binding site, as well as a conserved zinc binding domain. FtsH was first identified in E. coli where the enzyme functions both as an ATP-dependent protease and as a chaperone. Many phenotypes are conferred by ftsh mutations, and FtsH is thought to have both soluble and membrane-bound substrates. FtsH genes comprise a small gene family in cyanobacteria and higher plants. Its role in photosynthetic organisms is less clear than in E.coli, but it has been implicated in the assembly of components of the thylakoid membrane and in the D1 repair cycle. The present research focuses on the function of the four members of the FtsH gene family in the unicellular cyanobacterium, Synechocystis sp. PCC 6803: slr0228, sll1463, slr1390, and slr1604. Previous studies have shown that slr0228 mutations cause a reduction in Photosystem I, and that the protein product of this gene is important for repair of PSII under photoinhibitory conditions. In our poster we will describe progress in inactivating the cyanobacterial genes and in characterizing the mutant phenotypes.