摘要
旨在为研制沙门菌特异性抗菌制剂提供试验数据和参考,以禽源沙门菌为宿主菌,从鸡场污水中分离纯化沙门菌噬菌体,并对其生物学特性和基因组学进行研究。结果显示:分离到1株沙门菌烈性噬菌体S5,透射电镜下该噬菌体头部直径约50nm,尾部长约200nm,头部呈正二十面体对称,属有尾噬菌体目、长尾噬菌体科;该噬菌体对20株沙门菌的裂解率为75%,效价为8×10^(9)PFU·mL^(-1);在30~60℃作用30min和1h的效价基本不变;pH 4.0~11.0对噬菌体活性影响不明显;最佳感染复数为0.0001,一步生长曲线显示其感染宿主菌后5min内(潜伏期)效价基本保持不变,暴发期约为95min,平均裂解量为50PFU·cell^(1)。噬菌体S5是双股DNA病毒,基因组全长为72519bp,GC含量39.45%,含有9种tRNA,预测到109个ORF,未发现任何编码细菌毒力因子等有害产物的基因。沙门菌烈性噬菌体S5,裂解效果较好、对环境适应性强、遗传背景清楚,以期成为防控沙门菌的抗生素替代产品。
The current study aims to provide experimental data and references for the development of Salmonellaspecific antibacterial agents.Here,we isolated a Salmonellaphage from chicken farm sewage and studied its biological characteristics and genomics.The results showed that Salmonellaphage S5was isolated.Transmission electron microscopy showed that the phage was a long-tailed phage with a head diameter of about 50nm and a tail length of about 200nm.Its head was icosahedral symmetrical,belonging to Caudovirales,Siphoviridae.The phage has a lysis rate of 75%against 20strains of Salmonella,with a titer of 8×10^(9)PFU·mL^(-1).The phage titer remained basically unchanged at the temperature from 30to 60℃for 30min or 1h,with little effect on phage activity at pH4.0-11.0.The optimal MOI of phage was 0.0001.The one-step growth curve showed that its titer remained basically unchanged within 5min incubation period after infection with the host bacteria.The outbreak period was about 95min,and the average lysate was 50PFU·cell^(1).Phage S5was a double-stranded DNA virus.The genome was 72519 bp in length,and the GC content was 39.45%.It contained 9types of tRNAs and 109predicted ORFs.No harmful factors such as bacterial virulence factors had been found.Salmonellavirulent phage S5has good lysis effect,strong adaptability to the environment and clear genetic background.It is expected to become an alternative product of antibiotics for the prevention and control of Salmonella.
作者
岑鑫
阳亭亭
赵尊福
文永平
张焕容
CEN Xin;YANG Tingting;ZHAO Zunfu;WEN Yongping;ZHANG Huanrong(College of Animal and Veterinary Sciences,Southwest Minzu University,Chengdu610041,China;College of Food and Biological Engineering,Chengdu University,Chengdu610106,China)
出处
《畜牧兽医学报》
CAS
CSCD
北大核心
2022年第8期2677-2688,共12页
ACTA VETERINARIA ET ZOOTECHNICA SINICA
基金
四川省应用基础研究项目(2021YJ0286)
西南民族大学研究生创新型科研项目(ZD2022282)。
