奶牛乳房炎主要病原菌GapC蛋白生物信息学分析及抗原表位预测

Bioinformatics Analysis and Epitopes Prediction of GapC from the Main Pathogenic Bacteria Causing Cow Mastitis

奶牛乳腺炎是主要由病原菌感染引起的奶牛常见疾病,新型疫苗研发是防控奶牛乳腺炎的重要内容之一。引起奶牛乳腺炎的主要病原菌为链球菌和葡萄球菌,包括无乳链球菌、停乳链球菌、乳房链球菌、金黄色葡萄球菌和表皮葡萄球菌,它们都存在甘油醛-3-磷酸脱氢酶C(GapC),且均能诱导机体产生良好的抗感染免疫保护作用。但对链球菌和葡萄球菌GapC的交叉免疫原性分析和研究缺乏报道。研究从GenBank获取链球菌和葡萄球菌GapC基因序列,利用生物信息学软件对理化性质、同源性、T细胞和B细胞表位等进行分析。结果显示,这些病原菌GapC均由336个氨基酸组成的亲水性蛋白,且无规则卷曲占比较高,表明具有良好的抗原性;三种链球菌与两种葡萄球菌之间GapC的氨基酸序列同源性67.8%~69.9%,存在4个共同线性B细胞表位、9个共同CD4~+T细胞表位和9个共同CD8~+T细胞表位,表明有一定的交叉免疫原性,为进一步实验研究GapC交叉免疫原性提供重要参考。

Cow mastitis was a common disease caused mostly by bacterial infections.Research and development of new vaccine was an important task for the prevention and control of cow mastitis.The most common pathogens causing cow mastitis were streptococcus(namely Streptococcus agalactiae,Streptococcus dysgalactiae and Streptococcus uberis)and staphylococcus(namely Staphylococcus aureus and Staphylococcus epidermidis),which all had glyceraldehyde-3-phosphate dehydrogenase C(GapC).Studies have shown that the GapC from three streptococcus species or two staphylococcus species could induce immune protection against streptococcus or staphylococcus infection,but analysis and research of their cross immunogenicity were less reported.GapC from the species of streptococcus and staphylococcus was obtained to analyze bioinformatics and comparison of the physicochemical properties,homology,T cell and linear B cell epitopes.The results showed that the GapC from each species was composed of 336 amino acids and was a hydrophilic protein with a high proportion of irregular curl,representing good antigenicity.The amino acid sequence homology of GapC between three streptococcus species and two staphylococcus species was 67.8%-69.9%,and there were 4 common linear B cell epitopes,9 common CD4+T cell epitopes and 9 common CD8+T cell epitopes in their GapC,showing a certain cross-immunogenicity.These results provided a reference for further experimental research on the cross immunogenicity between GapC from the pathogens.