7株水产品来源的霍乱弧菌的全基因组特征分析

Genome-wide characterization of 7 strains of Vibrio cholerae isolated from aquatic products

中文关键词:  霍乱弧菌  毒力基因  血清型  全基因组测序

英文关键词:Vibrio cholerae  virulence genes  serotype  whole genome sequencing

中文摘要:

      背景 霍乱弧菌是能引起大范围流行的甲类传染病,其流行状况和致病特点引起人们高度关注。目的 了解辽宁省水产品中霍乱弧菌的污染情况、血清分型、毒力基因和全基因组的遗传特征。方法 2023年采集自辽宁省餐饮环节和流通环节的鱼类、腹足类、虾类和双壳类等水产样品共163份,进行霍乱弧菌的检测,对分离菌株进行血清分型、毒力基因检测和全基因组测序分析。结果 163份样品中共检出7株霍乱弧菌,检出率为4.3%,其中6株菌为非O1/0139群,1株为O1群稻叶血清型,所有分离株均不携带ctxAB基因,7株菌的基因组序列长度为3853887～4164351bp,GC含量为47.07～47.76%,编码序列数量为3370～3732个,串联重复序列数量为55～73个,基因岛的数量为4～11个。7个分离株包含588～603个毒力相关基因,携带耐药基因的数量为263～286个。7株霍乱弧菌共有2863个共有的基因家族,O1群稻叶血清型菌株含有104个特有基因家族,同源单拷贝基因构建进化树共分为两个簇,其中第一簇中包含2个分离株,且高度同源,第二簇中包含其他5株菌株。结论 7个霍乱分离株携带多种毒力相关基因和耐药基因,O1群稻叶血清型分离株各基因序列来源复杂,决定了其对环境的适应性。

英文摘要:

      Background Vibrio cholerae is a class A infectious disease that can cause a wide range of epidemics. Its epidemic status and pathogenic characteristics have attracted great attention.Objective To investigate the contamination, serotyping, virulence genes and genome-wide genetic characteristics of Vibrio cholerae in aquatic products in Liaoning Province.Methods A total of 163 aquatic samples of fish, gastropods, shrimps and bivalves were collected from catering and circulation links in Liaoning Province in 2023 for the detection of V.cholerae.Serotyping, virulence gene detection and whole genome sequencing analysis were performed on the isolated strains.Results A total of 7 strains of Vibrio cholerae were detected in 163 samples, with a detection rate of 4.3 %. Among them, 6 strains were non-O1 / 0139 group and 1 strain was O1 group rice leaf serotype. All isolates did not carry the ctxAB gene. The genome sequence length of 7 strains was 3853887 ~ 4164351 bp, the GC content was 47.07 ~ 47.76 %, the number of coding sequences was 3370 ~ 3732, the number of tandem repeat sequences was 55 ~ 73, and the number of gene islands was 4 ~ 11. The 7 isolates contained 588-603 virulence-related genes, and the number of drug resistance genes was 263-286. There were 2863 common gene families in the 7 strains of V.cholerae.There were 104 unique gene families in the O1 rice leaf serotype strain. The phylogenetic tree constructed by homologous single-copy genes was divided into two clusters. The first cluster contained two isolates and was highly homologous, and the second cluster contained five other strains.Conclusion Seven cholera isolates carried a variety of virulence-related genes and drug resistance genes. The gene sequences of O1 rice leaf serotype isolates were complex, which determined their adaptability to the environment.