Abstract
FtsH protease from higher plants is a member of ATP dependent intracellular protease. It is localized in thylakoid membrane, and known to degrade a photodamaged D1 protein in photosystem II.
We constructed overexpression system of FtsH homologous gene in Nicotiana tabacum. The full-length cDNA of FtsH protease was connected to pET vector to generate a T7-tag fusion protein. The membrane protein from plant species sometimes forms inclusion body in E.coli. However, in our system, recombinant protein was recovered in soluble fraction. The recombinant FtsH protease was purified near homogenously with T7-tag affinity column. The isolated FtsH protease exhibited Zn2+ and ATP dependent α-casein degradation activity as shown previously. In this study, we propose the kinetic properties of ATPase and protease activity of recombinant FtsH protease. In addition, the hydrolytic mechanism will also be discussed from inhibitor analysis.
