has role protective antigen role protective antigen Streptococcus agalactiae protein Rib protein Protegen ID: 860; NCBI Protein GI: 1620648; NCBITaxon: 1311 Oliver He Allen Xiang Vaccination of mice with the Rib protein protected against two strains of capsular type III and two strains of type II, and vaccination with the alpha protein protected against one strain of type II and one strain of type Ib [PubMed: 8751893].