학술논문
一株裂解性奶牛乳房炎源屎肠球菌噬菌体的分离及其生物学特性分析 / Isolation and Characterization of a Lytic Phage Infecting Enterococcus faecium of Bovine Mastitis
Document Type
Academic Journal
Author
张倩; 于会举; 孙耀强; 张湘莉兰; 张培生; 刘鸽; 屈勇刚; 童贻刚; 李岩; ZHANG Qian; YU Hui-ju; SUN Yao-qiang; ZHANGXIANG Li-lan; ZHANG Pei-sheng; LIU Ge; QU Yong-gang; TONG Yi-gang; LI Yan
Source
畜牧兽医学报 / Acta Veterinaria Et Zootechnica Sinica. 48(4):706-713
Subject
Language
Chinese
ISSN
0366-6964
Abstract
从新疆石河子地区奶牛粪样中分离裂解性屎肠球菌噬菌体,对其进行纯化及生物学特性分析,为治疗和控制细菌性感染提供基础.利用双层平板培养法从奶牛粪样中分离、纯化噬菌体,并观察噬菌斑特征,将纯化后的噬菌体浓缩液用磷钨酸负染,通过透射电子显微镜观察其形态特征.对该噬菌体进行全基因组测序和遗传进化分析,用双层平板培养法测定其宿主谱、最佳感染复数、一步生长曲线、热稳定性及pH稳定性.结果如下:分离并纯化出一株裂解性屎肠球菌噬菌体,命名为vB_EfaM_XJ3.其噬菌斑圆形透明、无晕环且边缘整齐,直径1.2～1.5mm;电镜观察其头部呈廿面体,头长约53.15 nm,尾长约14.42 nm×199.62 nm;核酸类型为dsDNA,基因组全长为157.189 kb,GC含量为50.27％;其基因序列与沙门菌噬菌体SKML-39的相似性高达98％.生物学特性研究显示vB_EfaM_XJ3目前只裂解其宿主菌;最佳感染复数为0.001,潜伏期为15 min,爆发期为175 min,裂解量约为84;能耐受50℃左右高温,在pH 5.0～11.0范围内效价稳定.分离鉴定出一株裂解性肌尾科屎肠球菌噬菌体,对它进行了生物学特性和亲缘性分析,为沙门菌和屎肠球菌抑菌剂的研究与应用奠定了基础.
The aim of the present study was to isolate and characterize the phage that could lyse Enterococcus faecium from fecal samples of dairy cattle in Shihezi,Xinjiang,and provide the basic data for the phage therapy as well as prevention.The phage was isolated and purified from dairy cattle fecal samples by double-layer agar plate method.And its plaque characteristics was observed.The purified phage was concentrated,negatively stained with phosphotungstic acid and observed by transmission electron microscopy.The genome of the isolated phage was sequenced.Its genetic and evolutional history were analyzed.The host range,optimal multiplicity of infection (MOI),one-step growth curve,temperature,and pH stability of the phage were investigated by double-layer agar plate methods.A lytic phage of Enterococcus faecium was isolated and purified,and named vB_EfaM_XJ3.The phage plaques were circular,clear and transparent with smooth edge,and its diameter was 1.2-1.5 mm.The electron microscope observation showed that the phage particles,whose head was twenty-sided,head length was about 53.15 nm,tail length was about 14.42 nm× 199.62 nm.The genome of the phage was comprised of double strand DNA,the size was 157.189 kb with GC content of 50.27％.The homology of amino acid sequence of phage vB_EfaM_XJ3 with Salmonella phage SKML-39 was 98％.The study of biological characteristics showed that the vB_EfaM_XJ3 only crack its host bacteria at present.The optimal MOI was 0.001,the incubation period was 15 min,the burst period was 175 min and the burst size was 84.The phage could withstand the temperature up to 50 ℃ and keep stable titer under pH 5.0-11.0.A lytic phage of Enterococcus faecium was isolated and identified.Its biological characteristics and genetic were analyzed.The results laid the foundation for the further research and application of the antibacterial agent for Salmonella and Enterococcus faecium.
The aim of the present study was to isolate and characterize the phage that could lyse Enterococcus faecium from fecal samples of dairy cattle in Shihezi,Xinjiang,and provide the basic data for the phage therapy as well as prevention.The phage was isolated and purified from dairy cattle fecal samples by double-layer agar plate method.And its plaque characteristics was observed.The purified phage was concentrated,negatively stained with phosphotungstic acid and observed by transmission electron microscopy.The genome of the isolated phage was sequenced.Its genetic and evolutional history were analyzed.The host range,optimal multiplicity of infection (MOI),one-step growth curve,temperature,and pH stability of the phage were investigated by double-layer agar plate methods.A lytic phage of Enterococcus faecium was isolated and purified,and named vB_EfaM_XJ3.The phage plaques were circular,clear and transparent with smooth edge,and its diameter was 1.2-1.5 mm.The electron microscope observation showed that the phage particles,whose head was twenty-sided,head length was about 53.15 nm,tail length was about 14.42 nm× 199.62 nm.The genome of the phage was comprised of double strand DNA,the size was 157.189 kb with GC content of 50.27％.The homology of amino acid sequence of phage vB_EfaM_XJ3 with Salmonella phage SKML-39 was 98％.The study of biological characteristics showed that the vB_EfaM_XJ3 only crack its host bacteria at present.The optimal MOI was 0.001,the incubation period was 15 min,the burst period was 175 min and the burst size was 84.The phage could withstand the temperature up to 50 ℃ and keep stable titer under pH 5.0-11.0.A lytic phage of Enterococcus faecium was isolated and identified.Its biological characteristics and genetic were analyzed.The results laid the foundation for the further research and application of the antibacterial agent for Salmonella and Enterococcus faecium.