[Recombinant expression, purification and adhesion function identify of Bacillus anthracis BslA(260 -652) protein]

To obtain the recombinant BslA(260-652) protein of Bacillus anthracis and prepare its antibody for the adhesion activity studies.

The fragment coding BslA(260-652) was cloned into pET28a(+) plasmid and induced to express recombinant protein in E. coli Rosetta (DE3) by Isopropyl beta-D-1-thiogalactopyranoside (IPTG). The expressed recombinant soluble protein was purified by a column packed with Ni Resin. Purified protein was used as the antigen to immunize BABL/c mice for three times to raise polyclonal antibody. The adhesion activity of BlsA(260-652) was detected by immunofluorescence experiments and bacterial adherence assays.

The purity of the purified soluble BslA(260-652) was about 87.4%. ELISA assay titer of antiserum from vaccinated mice reached 1:20000. Western blot showed the antiserum could specifically recognize endogenous BslA protein. The purified BslA(260-652) displayed a typical adhesion-like function. Either the anti-BslA serum or the BslA(260-652) protein could inhibit A16R's Hela adherence.

The recombinant BslA(260-652) protein was successfully obtained, which would lay the foundation for further research of the anthrax vaccine and the role of this S-layer protein in the pathogenesis of anthrax.