1株跨属感染猪霍乱沙门菌和大肠杆菌烈性噬菌体的分离及其生物学特性  

Isolation and Characterization of a Lytic Polyvalent Bacteriophage Infecting Salmonella choleraesuis and Escherichia coli

作　　者：张玉宇 张敏[1] 黄赞 林焱[1] ZHANG Yuyu;ZHANG Min;HUANG Zan;LIN Yan(Laboratory of Gastrointestinal Microbiology of Nanjing Agricultural University,Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal Health,National Center for International Research on Animal Gut Nutrition,Nanjing 210095,China)

机构地区：[1]国家动物消化道营养国际联合研究中心,江苏省消化道营养与动物健康重点实验室,南京农业大学消化道微生物研究室,南京210095

出　　处：《畜牧兽医学报》2020年第8期2032-2038,共7页ACTA VETERINARIA ET ZOOTECHNICA SINICA

基　　金：江苏省自然科学基金青年基金(BK20180540);江苏省农业科技自主创新资金(CX(19)3025)。

摘　　要：从健康猪肠道内容物分离鉴定猪霍乱沙门菌(Salmonella choleraesuis,S.choleraesuis)的烈性噬菌体,并对其进行生物学特性分析。以S.choleraesuis 13122为宿主菌,用双层平板法从猪肠道黏膜和食糜样品中分离噬菌体,用电镜形态观察和基因组测序确定其分类,用点滴法和双层平板法测定其在大肠杆菌上的宿主谱,用浊度法测定其裂菌效力。分离到1株猪霍乱沙门菌噬菌体,命名为沙门菌噬菌体L6jm(Salmonella phage L6jm)。L6jm头部呈正多面体直径约75 nm,具有非收缩性的尾部,长约190 nm,其基因组无整合酶基因和细菌基因组,故判定为烈性噬菌体;L6jm可感染S.choleraesuis 13122并跨属感染1株大肠杆菌(Escherichia coli,E.coli)244,同时,可裂解9株大肠杆菌,包括1株产肠毒素大肠杆菌(ETEC);L6jm在S.choleraesuis 13122和E.coli 244上的最佳感染复数分别为0.01和0.001;潜伏期均为15 min,暴发期分别为145和125 min;L6jm在≤50℃,pH为3~11时稳定;L6jm在液体培养基中对S.choleraesuis 13122有显著(P<0.05)的抑菌效果,对ETEC104在MOI 100时也可产生显著(P<0.05)的抑菌效果。L6jm可跨属感染S.choleraesuis和E.coli,且能裂解1株ETEC,具有防治沙门菌和大肠杆菌感染的应用潜力。This experiment was conducted to isolate and characterize a lytic bacteriophage against Salmonella choleraesuis(S.choleraesuis)from the healthy pig gut.Chyme and mucosal samples from pig jejunum and colon were assayed for the presence of bacteriophage capable of forming plaques on S.choleraesuis 13122.Bacteriophage classification was confirmed by TEM observation and sequencing.The host range was determined by the spot test method and double-layer agar plate method.Bacteriostatic ability was evaluated by turbidity measurement.A bacteriophage named L6jm was isolated,which had a regular polyhedron head approximately 75 nm in diameter and a long noncontractile tail with 190 nm in length.As the sequencing result showed no integrase or bacterial genome was in the genome of L6jm,L6jm was defined as lytic bacteriophage.L6jm can infect S.choleraesuis 13312 and Escherichia coli(E.coli)244.Also,L6jm lysed 9 E.coli strains including one enterotoxigenic E.coli(ETEC)strain.The optimal MOI of L6jm against S.choleraesuis 13122 and E.coli 244 were 0.01 and 0.001 respectively.The latent periods were both 15 min in two strains whereas the rise periods were 145 min and 125 min.L6jm was stable over a wide range of temperatures(30-60℃)and pH(3.0-11.0).L6jm could significantly(P<0.05)inhibit the growth of S.choleraesuis 13312,and inhibit ETEC 104 at MOI 100.The polyvalent bacteriophage L6jm infecting S.choleraesuis and E.coli as well as lysing ETEC104 has potential application value in preventing and controlling S.choleraesuis and E.coli infection.

关 键 词：猪霍乱沙门菌 噬菌体 跨属感染 生物学特性 裂菌效力 

分 类 号：Q939.48[生物学—微生物学]