plo基因的宿主关联性变异及其在化脓隐秘杆菌分型中的应用  

Host-associated variation of plo gene and its application in typing of Trueperella pyogenes

作　　者：沈克飞[1,2] 徐登峰 王孝友[1,2] 付利芝 陈春林[1,2] 张素辉 SHEN Kefei;XU Dengfeng;WANG Xiaoyou;FU Lizhi;CHEN Chunlin;ZHANG Suhui(Chongqing Academy of Animal Sciences,Chongqing 402460,China)

机构地区：[1]重庆市畜牧科学院,重庆402460 [2]重庆市兽用生物制品工程技术研究中心,重庆402460

出　　处：《中国生物制品学杂志》2024年第11期1300-1306,共7页Chinese Journal of Biologicals

基　　金：重庆市自然科学基金面上项目(CSTB2022NSCQ-MSXO449);重庆市财政资金专项(22537C)。

摘　　要：目的研究不同宿主源菌株plo基因突变规律及其系统发育关系,为表征菌株-宿主关联提供可行方法。方法采用PCR法从14株山羊分离株、2株猪分离株和2株绵羊分离株中扩增plo基因,并对其进行序列测定和序列拼接。将从18个菌株中得到的plo全基因与从GenBank中下载的plo全基因及其编码产物进行多序列比对和系统发育分析。结果18株分离株均获得了plo全基因,其同源性高于95%。plo基因有3种点突变模式,Ⅰ型由牛、马源菌株构成,有10个一致性突变位点;Ⅱ型由猪、狗源菌株构成,有22个一致性突变位点;Ⅲ型由山羊、绵羊、岩羚羊、林麝源菌株构成,有32个一致性突变位点。突变位点分散于plo基因的大部分区域;产生16个有义突变,导致PLO蛋白质也形成3种相应的点突变模式。在邻接法(neighbor-joining method,NJ)建立的plo全基因进化树中,化脓隐秘杆菌分为4个分支,牛、马源菌株聚类至Ⅰ群,猪、狗源菌株聚类至Ⅱ群,山羊、绵羊、岩羚羊、林麝源菌株聚类至Ⅲ群,1株梅花鹿分离株单独形成Ⅳ群。与plo全基因分型不同,在PLO全序列进化树中,1株梅花鹿分离株聚类至Ⅲ群。结论plo基因呈现出宿主关联性变异,通过构建plo全基因及PLO全序列进化树可展示菌株-宿主关联性,提示plo全基因及PLO全序列是表征菌株-宿主关联的可用分子标志。Objective To investigate the mutation patterns and phylogenetic relationships of the plo gene in strains from different hosts,and provide feasible methods for characterizing the strain-host association.Methods The plo gene was amplified using PCR from 14 strains isolated from goats,2 strains from pigs and 2 strains from sheep,and sequenced and spliced.Multiple sequence alignment and phylogenetic analysis were performed on the plo complete gene obtained from 18 strains,as well as the plo gene downloaded from Gen Bank,and their coding products.Results The plo complete gene was obtained from 18 isolates,and the homology was higher than 95%.The plo gene had three types of point mutation.TypeⅠwas composed of strains from bovines and a horse,with 10 consistent mutation sites;typeⅡwas composed of strains from pigs and a dog,with 22 consistent mutation sites;and typeⅢwas composed of strains from goats,sheep,a chamois and a forest musk deer,with 32 consistent mutation sites.The mutation sites were distributed dispersedly in most regions of the plo gene.These mutations produced 16 sense mutations,resulting in three corresponding point mutation patterns of PLO protein.Trueperella pyogenes(T.pyogenes)was divided into four branches in the plo complete gene phylogenetic tree established by the neighborjoining method(NJ).The bovine strains and a strain from horse were clustered into GroupⅠ,the strains from pigs and a dog into GroupⅡ,the strains from goats,sheep,a chamois and a forest musk deer into GroupⅢ,and the one strain from sika deer into GroupⅣalone.Different from plo genotyping,the one strain from sika deer was clustered into GroupⅢin the PLO phylogenetic tree.Conclusion The plo gene exhibits host-associated mutations.By constructing phylogenetic trees of the plo complete gene and PLO complete sequence,strain-host association can be demonstrated,indicating that the plo gene and PLO sequence are useful molecular markers for characterizing strain-host association.

关 键 词：化脓隐秘杆菌 plo基因 菌株-宿主关联性 点突变 进化树 分子标志 

分 类 号：S852.6[农业科学—基础兽医学]