In silico Design a vaccine Candidate against Corynebacterium diphtheriae

This study was undertaken to select and analyze epitopes of Corynebacterium diphtheriae toxin using online and offline computerized analysis methods, after that affinity of Major Histocompatibility Complex (MHC) epitopes to HLA-DRB1*0101 was analyzed by Hex-protein protein software. The B cell epitopes were predicted via Immune Epitope Database (IEDB) and MHC class II epitopes were predicted by Vaxign software. A physicochemical analysis of candidate vaccine revealed that the designed vaccine has a molecular weight of 59.062 kD. The estimated half-life of candidate vaccine was found to be greater than 30 hours (mammalian reticulocytes, in vitro), greater than 20 hours (yeast, in vivo), and greater than 10 hours (Escherichia coli, in vivo). The instability index (II) is computed to be 31.31 (<40), the aliphatic index was found to be 65.80, and the vaccine was considered stable. The grand average of hydropathicity was 0.580, therefore, the vaccine is a hydrophilic protein and probably it interacts with molecules of water. The result of allerTOP, ToxinPred showed that the vaccine is non-allergenic and non-toxic. According to the obtained data from protParam and pepCalc, our designed vaccine is soluble and no transmembrane helix was projected, hence no expression difficulties are anticipated in the development of the vaccine. The membrane helices value of vaccine was 33.64%. The result of protein protein docking analysis showed that maximum affinity of candidate vaccine to HLA-DRB1*0101 with the score of -636.85. The result of this study showed that the candidate vaccine can be stimulate HLA-DRB1*0101.