In silico Design of a Candidate Vaccine to Hasten Immune Responses against Group B Streptococcus Bacteria

Background: Streptococcus agalactiae (Group B Streptococcus) is a pathogen, that asymptomaticallycolonizes the genitourinary tract of healthy adults. Nevertheless, Group B Streptococcus carriage in pregnantwomen can lead to several health issues in newborns causing life-threatening infections, for example,pneumonia, sepsis, or meningitis. Immuno-informatics servers are cost-effective methods to boost the designof a skilled candidate vaccine against Streptococcus agalactiae. The use of vaccines has been confirmed tobe a hopeful immunization approach against bacteria due to the induction of long-term protective immunity.Methods: In the study, a complete in silico approach was conducted to design a vaccine composed ofcytotoxic T lymphocyte and helper T lymphocyte epitopes of Sip (surface immunogenic protein) and Alpproteins. The potential bacterial peptides as the candidate vaccine were screened regarding convenientfeatures like hydrophilicity, flexibility, and antigenicity. The final construct was fused with the assistance ofsuitable linkers and cloned in a pET۲۸a vector for the production of the vaccine in a bacterial host.Results: After validation of the vaccine construct in terms of its efficacy, stability, and exposure ability,molecular docking analysis was carried out to show its interaction with toll-like receptor ۴. The molecularsimulations by iMODS server confirmed the stability of the binding interface. Additionally, the in silicocloning of the assembled vaccine in pET۲۸a showed the possibility of producing a vaccine construct in E.coli.Conclusion: The in silico analysis indicated that the construct could be a potent candidate vaccine againstGroup B Streptococcus once its effectiveness is verified by experimental studies.