新型冠状病毒M蛋白结构和B细胞表位预测

Prediction of structure and B cell epitope of M protein of SARS-CoV-2

目的预测新型冠状病毒(SARS-CoV-2)M蛋白的结构及可能的B细胞优势表位。方法从NCBI GenBank数据库中检索SARS-CoV-2 M蛋白的氨基酸序列,应用计算机辅助生物信息学软件进行分析,利用ExPASy服务器上的ProtParam、SOPMA、GOR、Swiss Model分别预测M蛋白的理化性质、二级结构、三级结构;利用TMHMM、Phobius线上软件预测M蛋白的跨膜区域,并结合DNASTAR软件进行亲水性、柔韧性、表面可能性、抗原性及极性等综合分析;利用Vector NTI软件分析冠状病毒属M蛋白的同源性。结果 SARS-COV-2 M蛋白由222个氨基酸组成,为稳定的跨膜蛋白,以α螺旋为主。多种参数进行综合分析推测,其可能的B细胞优势表位为第5-14位氨基酸(NGTITVEELK)。SARS-CoV-2 M蛋白与SARS-CoV M蛋白、Bat SARS-like CoV的M蛋白同源性匹配最高,达90%。结论 5-14肽段为SARS-CoV-2 M蛋白可能的B细胞优势表位。本研究为实验确定SARS-CoV-2 M蛋白的B细胞表位、免疫识别提供了参考,为进一步研发疫苗奠定了基础。

Objective To predict the structure and possible B cell dominant epitopes of M protein of SARS-CoV-2.Methods The amino acid sequence of SARS-CoV-2 M protein was searched from the NCBI GenBank database and analyzed by using computer-aided bioinformatics software. The physic-chemical properties, secondary structure and tertiary structure of M protein were predicted by using ProtParam,SOPMA,GOR IV and Swiss Model on ExPASy server respectively,while the transmembrane region by using TMHMM and Phobius online software. The comprehensive analysis of hydrophilicity,flexibility,surface possibility,antigenicity and polarity were performed by using TMHMM and Phobius online software in combination with DNASTAR software. The homology of Coronavirus M protein was analyzed by using Vector NTI software. Results The SARS-COV-2 M protein consisted of 222 amino acids,which was a stable transmembrane protein mainly composed of α helix and random coil. Comprehensive analysis of various parameters speculated that the possible B cell dominant epitope was amino acids 5-14(NGTITVEELK). The M protein of SARS-CoV-2 showed the highest homology of 90% to those of SARS-CoV coronavirus and Bat SARS-like CoV. Conclusion The peptides 5-14 was a possible B cell dominant epitope of SARS-CoV-2 M protein. This study provided a reference for the experimental determination of B cell epitope of SARS-CoV-2 M protein and immune recognition,and laid a foundation of development of vaccines.