牛源无乳链球菌全基因组及致病特性分析  

Analysis of the complete genome and pathogenicity of Streptococcus agalactiae from bovine

作　　者：庞茂达[1,2] 杜加园[1,2] 张欣怡 丁浩 孙利厂 何涛[1] 刘永杰[2] 王冉[1] PANG Maoda;DU Jiayuan;ZHANG Xinyi;DING Hao;SUN Lichang;HE Tao;LIU Yongjie;WANG Ran(Key Laboratory of Food Quality and Safety of Jiangsu Province-State Key Laboratory Breeding Base/Institute of Food Safety and Nutritio,Jiangsu Academy of Agricultural Sciences,Nanjing 210014,China;College of Veterinary Medicine,Nanjing Agricultural University,Nanjing 210095,China;College of Veterinary Medicine(Institute of Comparative Medicine),Yangzhou University,Yangzhou 225009,China)

机构地区：[1]江苏省农业科学院农产品质量安全与营养研究所/江苏省食品质量安全重点实验室-省部共建国家重点实验室培育基地,南京210014 [2]南京农业大学动物医学院,南京210095 [3]扬州大学兽医学院(比较医学研究院),江苏扬州225009

出　　处：《扬州大学学报(农业与生命科学版)》2024年第6期56-64,共9页Journal of Yangzhou University:Agricultural and Life Science Edition

基　　金：江苏省农业科技自主创新资金项目[CX(22)3027];国家自然科学基金资助项目(32102709);江苏省自然科学基金资助项目(BK20170600);江苏省食品质量安全重点实验室-部省共建国家重点实验室培育基地自主研究课题(2019za011)。

摘　　要：无乳链球菌是引发奶牛乳腺炎的主要致病菌。为探究牛源无乳链球菌的致病特性,对其流行株NJ1606和YZ1605进行全基因组测序,并与已公布的22株牛源无乳链球菌进行基因组分析,解析其遗传进化、毒力因子、耐药基因和前噬菌体等信息,测定NJ1606和YZ1605生物被膜形成能力、黏附能力以及引发乳腺炎发生率等致病特征。结果表明:24株菌可分为15个序列型,并鉴定出23个毒力基因及5个耐药基因,其中21个基因组中至少含有1个完整的前噬菌体。此外,NJ1606和YZ1605均有较强的生物被膜形成能力,能高效地黏附于奶牛乳腺上皮细胞,在1×10^(5)CFU的剂量下,即可在小鼠乳腺内成功定殖并引发乳腺炎。这一研究不仅首次系统性地揭示牛源无乳链球菌的遗传信息,还为其致病机制的探索以及防控策略的制定提供科学依据。Streptococcus agalactiae is the main pathogen causing bovine mastitis.In this study,the complete genome of the epidemic strains of bovine S.agalactiae NJ1606 and YZ1605 was sequenced,and the genome was analyzed with 22 published strains.The genetic evolution,virulence factors,drug resistance genes,and prophages of were analyzed.The pathogenic characteristics of NJ1606 and YZ1605,such as biofilm formation ability,adhesion ability and the incidence of mastitis,were also determined.The results showed that 24 S.agalactiae strains could be divided into 15 sequence types.Twenty three virulence genes,as well as 5 drug resistance genes,were identified.All 21 genomes contained at least one complete prophages.In addition,both NJ1606 and YZ1605 showed strong biofilm formation ability and could adhere to the bovine mammary epithelial cells efficiently.At a dose of 1×10^(5)CFU,these two strains can successfully colonize in the mouse mammary gland and cause typical mastitis symptoms.This study not only systematically revealed the genetic information of bovine S.agalactiae for the first time,but also provided important scientific basis for the exploration of its pathogenic mechanism and the formulation of prevention and control strategies.

关 键 词：奶牛 无乳链球菌 全基因组 致病特性 

分 类 号：S855.11[农业科学—临床兽医学]