Bioinformatics analysis of candidate proteins Omp2b, P39 and BLS for Brucella multivalent epitope vaccines

This study focuses on analyzing the physicochemical properties, structural characteristics and dominant epitopes of Brucella outer membrane protein 2b (Omp2b), periplasmic binding protein (P39) and Brucella lumazine synthase (BLS) proteins by bioinformatics methods, and to provide a theoretical basis for constructing multi-epitope vaccines. The amino acid sequences of three kinds of proteins were obtained from the UniProt database. The highest frequency alleles in northern China were obtained from the AlleleFrequencies database. Analysis of the physicochemical properties of the proteins by ProtParam online software. Analysis of the secondary structure of the proteins were predicted by SOMPA online software. Using SWISS-MODEL online software constructed and analyzed the tertiary structure of the proteins. Using ABCpred, BepiPred, BCPred and SVMTrip online software analyzed linear B cell epitopes of proteins, The T cell dominant epitope of the protein was analyzed using SYFPEITHI, RANKPEP and IEDB online software. Omp2b was identified three linear B cell dominant epitopes, five CD8⁺ T cell dominant epitopes, and three CD4⁺ T cell dominant epitopes. P39 was identified three linear B cell dominant epitopes, two CD8⁺ T cell dominant epitopes, and two CD4⁺ T cell dominant epitopes. BLS was identified one linear B cell dominant epitope, one CD8⁺ T cell dominant epitope, and two CD4⁺ T cell dominant epitopes. The results indicated that epitope prediction of three Brucella vaccine candidate proteins can provide a theoretical basis for the construction of an ideal multivalent epitope vaccine against Brucella.