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严重急性呼吸综合征(SARS)是一种新发现的急性传染病。对一株已确认为SARS病原体的冠状病毒(BJ01)进行了全基因组序列测定,并与其他已知病毒进行了比较分析。该病毒基因组全长为29.725kb,含11个可读框(ORFs),由1个稳定区和1个可变区组成,其中稳定区编码RNA依赖性RNA聚合酶,包括两个ORFs;可变区含有4个蛋白质编码序列(CDSs),分别编码病毒的4个结构蛋白(S,E,M,N蛋白)。此外,可变区还包括5个非典型的预测蛋白(PUPs)。此病毒基因的排列顺序与其他已知的冠状病毒一致。通过与已知RNA病毒的序列比对,可以确认该病毒属于冠状病毒科(Coronaviridae)。与GenBank中已知的5个SARS相关病毒全基因组序列的比较分析显示,已在30个核苷酸位置上检出序列差异,总体突变率为0.1％,其中15个变异位点在编码区,可能会导致蛋白质的氨基酸改变(异义突变)。S蛋白中已发现3处可能引起该蛋白质物化特征变化的变异,而该蛋白质可能参与病毒与宿主间的免疫反应.与病毒包膜形成相关的M蛋白中则已发现两处氨基酸变化。进化分析表明,SARS病毒可能不是来源于人类,但没有证据证明是人为制造的。为了阐明SARS相关病毒的病因学以及排除其他可能的SARS病原体的存在,仍需进行更深入的研究。
Severe Acute Respiratory Syndrome (SARS) is a newly discovered acute infectious disease. A complete genome sequence of a coronavirus (BJ01) that has been confirmed as a SARS pathogen was determined and compared with other known viruses. The full-length of the virus genome is 29.725kb, contains 11 open reading frames (ORFs), composed of one stable region and one variable region, wherein the stable region encodes RNA-dependent RNA polymerase, including two ORFs; variable The region contains four protein coding sequences (CDSs) that encode the four structural proteins (S, E, M, N) of the virus, respectively. In addition, the variable region also includes five atypical predicted proteins (PUPs). The order of the virus genes is consistent with other known coronaviruses. By sequence alignment with a known RNA virus, it was confirmed that the virus belonged to Coronaviridae. Compared with the known genome sequences of five SARS-related viruses in GenBank, there was a sequence difference of 30 nucleotides detected, with an overall mutation rate of 0.1%. Among them, 15 were located in the coding region, May cause protein amino acid changes (synonymous mutations). S protein has been found in three possible changes in the physical and chemical characteristics of the protein variation, and the protein may be involved in the immune response between the virus and the host.With the M envelope protein in the virus has found two amino acid changes. Evolutionary analysis shows that the SARS virus may not be derived from humans, but there is no evidence that it is artificially made. In order to elucidate the etiology of SARS-associated viruses and to exclude the presence of other possible SARS pathogens, more research is still needed.