羊种布鲁氏菌OMP16蛋白结构的生物信息学分析

目的 使用生物信息学方法预测羊布鲁氏菌OMP16蛋白的结构特点,并预测可能的B细胞和T细胞优势表位。方法 从NCBI数据库中获取羊布鲁氏菌的OMP16蛋白的氨基酸序列。通过ProtParam分析OMP16蛋白的理化性质;利用DNAstar和SOMPA分析OMP16蛋白二级结构;利用Phyre2和Rasmol构建并分析OMP16蛋白三级结构;利用IEDB、DNAStar、ABCpred和BepiPred预测OMP16蛋白的B细胞抗原表位;利用SYFPEITHI和IEDB预测OMP16蛋白的T细胞抗原表位。结果 OMP16蛋白有426个氨基酸序列,理论等电点为9.72,原子组成为C2026H3209 N499O536S17,为稳定性疏水性蛋白。二级结构显示α-螺旋、β-折叠、β-转角和无规则卷曲分别是40.61%,19.01%,8.45%和31.92%。预测出4个B细胞优势表位,分别是93-102,183-187,273-289,294-301;5个CTL细胞优势表位,分别是69-77,175-183,267-275,373-381,408-416;5个Th细胞优势表位,分别是4-20,32-46,63-77,316-330,352-366。结论 羊布鲁氏菌OMP16蛋白结构中有4个B细胞优势表位,5个CTL细胞优势表位和5个Th细胞优势表位,为进一步为布鲁氏菌诊断和疫苗研究的奠定基础。

Bioinformatics analysis of OMP16 protein structure of Brucella melitensis

We investigated OMP16 protein structures in Brucella melitensis and predict its possible dominant epitopes of B cell and T cell using bioinformatical methods. For OMP16 protein in Brucella melitensis, after acquiring its amino acid sequence from NCBI database, its physicochemical properties were analyzed with ProtParam and its secondary structures with SOMPA and NDAstar's Protein module; further, its tertiary structures were constructed with Phyre2 and analyzed with Rasmol; finally, its epitopes of B cells were predicted with IEDB, DNAstar and BepiPred, as well as those of T cells with SYFPEITHI and IEDB. Results showed that as a stable hydrophobic protein, OMP16 includes 426 amino acid sequences with isoelectric point at 9.72 and atomic composition as C₂₀₂₆H₃₂₀₉N₄₉₉O₅₃₆S₁₇. Its secondary structures showed that the proportions of α-helix, β-fold, β-corner and random coil were 40.61%, 19.01%, 8.45% and 31.92%, respectively. The predicted dominant epitopes were 93-102, 183-187, 273-289 and 294-301 for B cells, 69-77, 175-183, 267-275, 373-381 and 408-416 for CTL cells, and 4-20, 32-46, 63-77, 316-330 and 352-366 for Th cells. By analyzing four dominant epitopes for B cells, five for TCL cells and five for Th cells with bioinformatical methods, this study provided a firm foundation for next stage diagnosis of Brucella melitensis and its vaccination study.