猪冠状病毒与SARS-CoV-2的S基因及其蛋白结构差异分析

Analysis of S gene and protein structure difference between porcine coronavirus and SARS-CoV-2

自2019年12月以来,由SARS-CoV-2感染造成的COVID-19对全球人类的健康构成了巨大威胁。为研究SARS-CoV-2与猪冠状病毒之间的相关性,本实验采用生物信息学分析方法对SARS-CoV-2和常见猪冠状病毒的纤突(S)蛋白氨基酸序列进行遗传进化分析、对S蛋白S1亚基的受体结合域空间结构进行相似性分析,并采用双抗原夹心ELISA试剂盒检测了常见猪冠状病毒阳性血清中的SARS-CoV-2抗体。结果显示,SARS-CoV-2与猪冠状病毒的遗传关系较远,其S1亚基的受体结合域空间结构差异大,常见猪冠状病毒阳性血清中的SARS-CoV-2特异性抗体均为阴性。表明SARS-CoV-2与猪冠状病毒亲缘关系远,难以通过感染猪进而接触人类以实现跨物种感染,威胁公共卫生安全的风险极小。本研究为COVID-19病原溯源与跨物种生物安全性分析提供基础。

The pandemic of COVID-19(Corona virus disease 2019)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)poses a huge threat to human health worldwide since December 2019.In order to study the correlation between SARS-CoV-2 and porcine coronavirus,the phylogenetic analysis of spike(S)protein amino acid sequence of human coronavirus and porcine coronavirus,the similarity analysis of the spatial structure of S1 subunit receptor binding domain(RBD)of S protein were conducted by bioinformatics analysis,moreover,the double-antigen sandwich ELISA kit was utilized to detect the SARSCoV-2 antibody in common porcine coronavirus positive serum.The results of phylogenetic analysis showed a low identity of S protein amino acid sequence between SARS-CoV-2 and porcine coronavirus,indicating a long distance of genetic evolution,and the S1 subunit RBD spatial structure showed huge differences,meanwhile,all of the porcine coronavirus positive serum samples tested were negative of SARS-CoV-2 antibody.Our data suggested the huge differences in gene and protein level between SARS-CoV-2 and porcine coronavirus,which indicating that SARS-CoV-2 shows a minimal risk of achieving cross-species transmission by infecting pigs to threaten public health security.This research provides a basis for studying COVID-19 pathogen traceability and biosafety analysis of cross-species transmission.