Construction and Expression of CpxP Protein from Plant Pathogenic Bacteria

The CpxA/R signal transduction system is one prevalent two-component systems (TCSs) in gram-negative bacteria involved in the process of bacterial adherence, invasion, motility and cell division. CpxP is the auxiliary inhibitor of Cpx-two-component system in Escherichia Coli. However, the functions of Cpx pathway in gram-negative plant pathogenic bacteria are still unknown. Previous results showed that cpxP deleted S. typhimurium is more invasive, therefore CpxP was spectulated as an inhibitor of Cpx-signalling-cascade in plant pathogenic bacteria and inhibiting its invasion to the host. To obtain the structural information of CpxP in plant pathogenic bacteria for its pathogenic research, here, for the first time, the cpxP gene from Pectobacterium carotovorum subsp. carotovorum (PC1), a plant pathogenic bacterium, was cloned into pET15b plasmid for further expression in BL21 (DE3) strain. In this study, the vector with cpxP gene was constructed which provides a way to express and purify the CpxP protein for further structural and functional studies from plant pathogenic bacteria.