Objective This study aimed to clone the type Ⅱ fimA gene of Porphyromonas gingivalis(P. gingivalis) and detect its expression in Escherichia coli(E. coli). Methods The type Ⅱ fimA gene was obtained by polymerase chain reaction(PCR) from the genome of P. gingivalis to construct a prokaryotic expression plasmid pET-FimA. pET-FimA was transformed into E. coli BL21(DE3) competent cells, and the recombination protein was characterized via sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE) and Western blot analysis. Results DNA sequencing showed that the fragment was 95% consistent with that of published literature. We successfully constructed prokaryotic expression plasmid pET-FimA. Conclusion The plasmid efficiently expressed the recombinant fimbriae protein of the type ⅡfimA gene of P. gingivalis. A high purity of protein FimA was obtained. FimA has immunogenicity and immune reactivity.
