Prediction and Identification of B Cell Epitopes of GapC Protein of Streptococcus agalactiae
To express the Glyceraldehyde-3-Phosphate Dehydrogenase(GapC)protein of Streptococcus agalactiae from bovine and evaluate its immune effect,predict and identify its dominant B cell epitope.In this study,the GapC gene of Streptococcus agalactiae X16087 strain was amplified and the recombinant plasmid pET-28a-WR-X16087 was constructed.After induction and expression,purified GapC protein was used to immunize mice and the immune effect was analyzed.Then bioinformatics analysis was performed to predict and identify the B cell epitopes of GapC protein.The results showed that after induction and purification,the target protein with a size of 44 kDa was obtained.After immunizing,the mice antibody ti-ter reached 1∶218700,and the antibody subtypes mainly were IgG1 and IgG2b;mice protection could reach 100%.GapC immunization could significantly reduce the bacterial load in liver,spleen,lung and kid-ney of mice.GapC protein could reduce the pathological damage caused by bacterial invasion in mice.The B cell epitopes of GapC were predicted and screened.Based on the specific antibodies,three linear B cell epitopes of GapC were identified:46KYDTTQGRFDGTVEVKDG63,121TAPGGNDV128,186MVLDGPHR-GGDLRRAR201.The finding showed that the three B cell epitopes had the potential to be used in prophy-lactic epitope vaccines against bovine mastitis of Streptococcus agalactiae.
Streptococcus agalactiaeGapC proteinimmune effectB cell epitopesscreening and iden-tification