摘要
目的扩增分枝杆菌噬菌体D29LysinB基因,对其编码蛋白序列进行生物信息学分析。方法提取分枝杆菌噬菌体D29基因组DNA,PCR扩增LysinB基因并对扩增产物测序;通过在线ProtParam、SOPMA、TMHMM、SWISS-MODEL等程序分析D29LysinB编码蛋白的生物学特征。结果噬菌体D29LysinB基因全长765bp,与预期大小基本一致;基因序列与Genbank上公布的MTB标准株同源性为100%。噬菌体D29LysinB蛋白共254个氨基酸,分子式为C1304H1993N349O358S7,理论等电点为5.78,平均疏水系数为-0.151,为亲水性蛋白。二级结构中α-螺旋、β-折叠、β-转角和无规则卷曲分别占45.67%、10.63%、7.87%和35.83%。噬菌体D29LysinB蛋白是非跨膜或分泌蛋白。预测的B细胞抗原表位为11-28,38-46,50-55,69-75,120-127,132-139,161-171,173-177,210-213,234-237;Th细胞抗原表位为33-47,151-165,100-114,201-215,219-233,223-237,44-58,47-61,158-172,165-179,176-190,235-249;CTL细胞抗原表位为102-110,143-151,52-60,60-68,95-103,217-225,56-64,175-183,240-248,45-53,150-158,199-207。该蛋白与噬菌体Chy5LysinB蛋白进化距离较近。结论生物学信息学方法分析噬菌体D29LysinB蛋白为亲水性蛋白,含有B、Th及CTL细胞其抗原表位,为研究该蛋白在分枝杆菌中的功能奠定了基础。
Objective To express I.ysinB gene of mycobacteriophage D29 and bioinformatically analyze the protein se quence. Methods Genomic DNA of mycobacteriophage D29 was extracted. LysinB gene was amplified by PCR and products were sequenced. The structure, function and evolution were predicted by biological software. Results The RCR product of LysinB was 765bp, which is consistent with the expected size. Sequencing indicated that the sequence was consistent with that in GenBank. LysinB protein was consistent of 254 amino acids and its molecular formula was C1304H1993N3490358S7, theoretical isoelectric point was 5.78, the grand average of hydropathicity was -0. 151, gen erally it was a hydrophilic protein. Its secondary structure consisted of α-helixes（45.67 % ）, β-folds（10.63 % ）, Q-corners （7.87%）, and random coils（35.83%）. It was not transmembrane or secretory protein. Predicted epitodes of B cell were 11-28, 38-46, 50-55, 69-75, 120-127, 132-139, 161-171, 173-177, 210 213, 234-237; Th cell were 33- 47, 151-165, 100-114, 201-215, 219-233, 223-237, 44-58, 47 61, 158 172, 165-179, 176-190, 235- 249; CTLcelIwere 102-110, 143-151, 52-60, 60-68, 95-103, 217-225, 56-64, 175-183, 240-248, 45- 53, 150-158, 199 207. It was most closest with bacteriophage Chy5 LysinB protein. Conclusion Mycobacteriophage D29 LysinB protein was expressed successfully. We speculate its epitodes and evolution, which laid the foundation for the functional study of mycobacterium.
出处
《中国病原生物学杂志》
CSCD
北大核心
2017年第2期106-109,共4页
Journal of Pathogen Biology
基金
国家自然科学基金项目(No.81470001
No.81100006)
