Production of a Spbhp-37 recombinant protein and antibodies against it. The Spbhp-37 encoding gene was cloned in the pGEX-6P-1 vector, the recombinant protein was expressed in E. coli bacteria (BL21 strain) and purified. Then, this protein was used as antigen to obtain specific antibodies against it. Finally, antibodies were utilized in western blotting assays on the recombinant protein and total extracts of S. pneumoniae. (A) Production and purification of the Spbhp-37 recombinant protein. Proteins were analyzed by 12% SDS-PAGE stained with coomassie blue. Lane 1, total proteins of non-induced bacteria; lane 2, total proteins of IPTG-induced bacteria; lane 3, soluble fraction of IPTG-induced bacteria; lane 4, insoluble fraction of IPTG-induced bacteria; lane 5, solubilization of inclusion bodies; lane 6, purified protein. (B) Western blotting on purified recombinant protein. Lane 1, western blotting using an antibody directed against the GST tag; lane 2, western blotting using an antibody directed against the recombinant protein (anti-Spbhp-37). (C) Proteins were analyzed by 12% SDS-PAGE stained with coomassie blue and western blotting on total proteins of S. pneumoniae. Lane 1, total extracts of S. pneumoniae were analyzed by 12% SDS-PAGE stained with coomassie blue; lane 2, western blotting using the pre-immune serum; lane 3, western blotting using anti-Spbhp-37 antibodies; lane 4, western blotting using anti-GST. Molecular weight markers are indicated on the left. Arrows indicate the antibodies recognition of recombinant protein Spbhp-37.