1株羊源马链球菌的生物学特性及全基因组测序分析  

Biological characteristics and whole-genome sequencing analysis of a strain of sheep-derived Streptococcus equi

作　　者：马弘财 曾江勇[1] 元振杰[1] 旺加 王冬经 MA Hongcai;ZENG Jiangyong;YUAN Zhenjie;WANG Jia;WANG Dongjing(Xizang Livestock Research Institute,Xizang Academy of Agricultural and Animal Husbandry Sciences,Lhasa 850009,China;Sangzhuzi District Service Center for Agriculture and Animal Husbandry in Shigatse City,Xizang 857000,China)

机构地区：[1]西藏自治区农牧科学院畜牧兽医研究所,西藏拉萨850009 [2]日喀则市桑珠孜区农牧综合服务中心,西藏日喀则857000

出　　处：《中国兽医学报》2024年第6期1148-1155,共8页Chinese Journal of Veterinary Science

基　　金：日喀则市区域科技协同创新专项资助项目(QYXTZX-RKZ2023-05);中央引导地方发展资金资助项目(XZ202001YD0025C)。

摘　　要：为研究马链球菌的生物学特性及全基因组序列,对本实验室保存的1株羊源马链球菌进行复苏、生化试验、药敏试验及动物试验,随后通过全基因组测序并利用生物基因数据库对基因组的基因功能进行注释。生化鉴定结果显示,该菌株能发酵糖类,但硝酸盐、过氧化氢酶、V-P试验、M-R试验结果为阴性;药敏试验结果显示,该菌株对绝大部分抗生素呈高度敏感,对卡那霉素、丁胺卡那呈耐药;动物试验显示,该菌株对小鼠的致死率为100%,并测得该菌株的半数致死量为4.86×10^(6)CFU/kg;小鼠的病理切片结果显示:肺脏、肝脏、肾脏、脾脏均有不同程度的病变;全基因组测序结果显示,该菌株基因组总长为2272497 bp,G+C的含量为41.1%,预测含有2124个CDS区;RNA预测结果显示:rRNA的数量为15个,tRNA数量为57个含有4个前噬菌体和基因岛,VFDB数据库中有362个与致病性相关的基因,不含CRISPR序列。本研究解析了羊源马链球菌的全基因组,同时也为该病的治疗与防控提供了理论依据。In order to study the biological characteristics and whole-genome sequence of Streptococcus equi,a sheep-derived Streptococcus equi preserved in our laboratory was subjected to recovery,biochemical experiments,drug susceptibility tests and animal experiments,and followed by whole genome sequencing and annotation of the gene functions of the genome by using the biogenetic database.The biochemical identification results showed that this strain could ferment sugars,but the results of nitrate,catalase,V-P test,and M-R test were negative;the drug susceptibility test results showed that this strain was highly sensitive to most antibiotics and was resistant to kanaphylaxis.It was resistant to amikacin and amikacin;animal experiments showed that the lethality rate of this strain to mice was 100%,and the median lethal dose of this strain was measured to be 4.86×10^(6)CFU/kg.According to the pathological section results of mice,it showed that the lungs,liver,kidneys,and spleen all had varying degrees of lesions.The whole genome sequencing results showed that the total genome length of this strain is 2272497 bp,the G+C content was 41.1%,and it was predicted to contain 2124 CDS regions.The RNA prediction results showed that the number of rRNA and tRNA was 15,and the number of tRNA was 57.There were four prophages and gene islands,and there were 362 pathogenicity-related genes in the VFDB database without CRISPR sequences.This study analyzed the complete genome of Streptococcus equi derived from sheep,and also provided a theoretical basis for the treatment,prevention and control of the disease.

关 键 词：马链球菌 羊 生物学特性 全基因组 耐药试验 

分 类 号：S852.61[农业科学—基础兽医学]