云南省2019年首次发现的G基因型腮腺炎病毒全基因组序列特征

Characterization of whole genome sequences of G genotype mumps viruses first found in Yunnan province in 2019

目的分析云南省首次发现的G基因型腮腺炎病毒(Mumps virus,MuV)分离株全基因组序列特征。方法对云南省2019年1起流行性腮腺炎(流腮)暴发疫情中流腮病例采集咽拭子标本进行MuV核酸检测、分离培养和全基因组序列测定,构建全基因组和SH基因序列系统进化树,分析分离株核苷酸同源性和氨基酸差异。结果共获得4株MuV分离株全基因组序列,均为G基因型,SH基因序列完全一致,与中国其他省份G基因型分离株的同源性为91.47%-98.04%。4株分离株基因组全长为15358-15384个核苷酸,在蛋白编码区域无氨基酸差异;与中国S79疫苗株相比,核苷酸同源性为94.58%-94.59%,在7个编码蛋白上存在3个(M蛋白)至34个(HN蛋白)氨基酸差异,在HN和N蛋白已知抗原相关位点上分别有12个位点和8个位点出现氨基酸变异。结论云南省2019年首次发现的G基因型MuV与疫苗株相比全基因组序列存在一定差异;需持续开展MuV分子流行病学监测。

Objective To characterize whole genome sequences of G genotype mumps viruses(MuV)first found in Yunnan province.Methods We collected throat swab samples of mumps cases during a mumps outbreak in Yunnan in 2019 for MuV nucleic acid detection,isolation and culture,and whole genome sequencing.We constructed phylogenetic trees of whole genome and SH gene sequences of isolates and analyzed nucleotide homology and amino acid differences.Results Four MuV isolates were obtained and identified as G genotype,with completely consistent SH gene sequence and 91.47%-98.04%homologies compared with G genotype isolates from other provinces in China.Lengths of the whole genome for the four isolates ranged from 15358 to 15384 nucleotides,with no amino acid differences in protein-coding regions.Compared with the Chinese vaccine strain S79,nucleotide homologies of the four isolates were 94.58%-94.59%;there were 3(M protein)to 34(HN protein)amino acid differences in the 7 coding proteins,and 12 and 8 amino acid variations at the known antigen-associated sites of HN and N proteins.Conclusions The whole genome sequence of G genotype MuV first discovered in Yunnan in 2019 was different from that of the vaccine strain.We suggest continuously monitoring MuV molecular epidemiology.