A study of recombinant Vibrio cholera toxin-coregulated pili A (TCPA) from E.coli

Vibrio cholerae is a gram-negative bacterial pathogen that causes diarrheal disease cholera. One of the most pathogenic factors of Vibrio cholera is pili. Pili plays an important role in colonization and persistence of bacteria in small intestine.

In this study, pili A (tcpA) gene was amplified by Polymerase chain reaction (PCR) method and sub-cloned into expression vectors such as pGEX4T-1. Escherichia coli competent cells were transformed by recombinant plasmids and the expression of protein with IPTG. The recombinant proteins were purified by affinity chromatography (GST) and immunoblot analysis was used for evaluation of new recombinant proteins antigenicity. The concentration of recombinant proteins was measured according to Bradford assay.

The results of this study indicated that recombinant proteins were expressed successfully in competent cell of E. coli, such as E. coli BL21 (DH3). The recombinant protein was purified by affinity chromatography (GST). The immunoreactivity pattern of anti-Tcp antibody with recombinant proteins of TcPA showed that the recombinant proteins had antigenic properties.

Because these recombinant proteins are antigenic, these proteins may be considered as tentative candidates for designing cholera vaccine.