Abstract
FtsH protease is an ATP dependent protease. This protease localized on thylakoid membrane. Main function of FtsH protease is considered to be quality control of membrane proteins in the thylakoid membrane. D1 protein which is important component of photosystem II is one of the substrate proteins of FtsH protease. FtsH deficit mutant shows variegated phenotype, thus this protease plays an important role in the biogenesis of chloroplast. Structure of this enzyme is consisted from three domains, transmembrane domain, ATPase domain, and protease domain. Substrate protein forced to be denatured in the ATPase domain, successively transferred to the protease domain. The denatured substrate was digested in the protease domain. Arabidopsis contained 12 isoforms of FtsH proteases in the nuclear genome. Mutation in FtsH5 showed strong variegated phenotype. In this study, we constructed an expression system of ATPase domain in FtsH5. Biochemical and kinetic properties of expressed protein were analyzed.
