肠炎沙门菌噬菌体vB_SalP_QS的生物学特性及治疗小鼠沙门菌肠道感染的研究  

Biological characterization of Salmonella enterica phage vB_SalP_QS and treatment of Salmonella enteric infection in mice

作　　者：梁芮萁 黄淇星 王璐 王顺 白慧方 李俊 艾泽 张蕾 LIANG Ruiqi;HUANG Qixing;WANG Lu;WANG Shun;BAI Huifang;LI Jun;AI Ze;ZHANG Lei(College of Animal Science and Technology|College of Veterinary Medicine,Jilin Agricultural University,Changchun 130118,China;Changchun Borui Science&Technology Co.,Ltd,Changchun 130051,China)

机构地区：[1]吉林农业大学动物科学技术学院|动物医学院,长春130118 [2]长春博瑞科技股份有限公司,长春130051

出　　处：《中国农业大学学报》2024年第9期90-101,共12页Journal of China Agricultural University

基　　金：2023年吉林省博士后优先资助项目;吉林农业大学国家级大学生创新创业训练计划项目;吉林省自然科学基金(20220101311JC)。

摘　　要：为探索针对耐药沙门菌的噬菌体治疗方法,以沙门菌SE-21为宿主菌,从污水中分离得到一株烈性噬菌体并命名为vB_SalP_QS。在鉴定vB_SalP_QS生物学特性的基础上,对vB_SalP_QS和vB_SalP_SE29混合噬菌体治疗由沙门菌SE-21引起小鼠肠炎的治疗效果进行评价。结果表明:1)电镜观察可见该噬菌体属于有尾病毒目(Caudovirales),其效价为8×10^(8) PFU/mL。2)vB_SalP_QS的最佳感染复数(MOI)为0.01,潜伏期为40 min,裂解期为50 min。温度为4~60℃具有较好的活性,在pH 4~pH 10范围内非常稳定。平板点滴法试验表明vB_SalP_QS可以裂解17株沙门菌,裂解率为44.7%。3)噬菌体vB_SalP_QS的全基因组测序分析显示,噬菌体vB_SalP_QS全长42293 bp,GC含量为49%,共含有72个开放阅读框,且不含有溶源性、毒力因子及整合酶基因。4)小鼠体内治疗试验显示,宿主菌SE-21对小鼠最小致死量为5×10^(8) CFU/mL,感染小鼠经vB_SalP_QS(100μL 1×10^(7) PFU/mL)和vB_SalP_SE29(100μL 1×10^(7) PFU/mL)混合治疗后存活率为100%,单独用vB_SalP_QS治疗组(200μL 1×10^(7) PFU/mL)的小鼠存活率为80%,单独用vB_SalP_SE29治疗组(200μL 1×10^(7) PFU/mL)的小鼠存活率为70%,对照组全部死亡。5)病理组织观察表明,混合噬菌体可以有效杀灭沙门菌SE-21的同时,还能更好地保护小鼠肠绒毛,可显著提高感染SE-21的小鼠存活率。综上,噬菌体vB_SalP_QS具有良好的酸碱稳定性、热稳定性以及安全性,混合噬菌体联合治疗效果优于噬菌体单一治疗。本研究为噬菌体制剂治疗沙门菌感染提供了重要依据,也为混合噬菌体鸡尾酒疗法的临床应用奠定基础。In order to study the phage therapy methods for drug-resistant Salmonella,a virulent bacteriophage was isolated from sewage with Salmonella SE-21 as the host bacterium and named vB_SalP_QS.On the baisis of identifying the biological characteristics of vB_SalP_QS,vB_SalP_QSand vB_SalP_SE29 hybrid phage for the treatment of enteritis in mice caused by SE-21 was evaluated.The results showed that:1)The phage belonged to the order of caudoviruses(Caudovirales)by electron microscopy.The potency of the phage was 8×10^(8) PFU/mL.2)Biological characterization showed that the phage vB_SalP_QS had an optimal multiplicity of infection(MOI)of 0.01,with an incubation period of about 40 min,and a lysis period of about 50 min.It had good activity at temperatures ranging from 4℃to 60℃,and it was very stable within the range of pH 4-pH 10.vB_SalP_QS could lyse 17 strains of Salmonella by The plate spot test.The cracking rate was 44.7%.3)The phage vB_SalP_QS was 42293 bp in total length,had a GC content of 49%,contained a total of 72 open reading frames(ORFs),and had no lysogeny,virulence factors,and integrase genes.4)In vivo therapeutic tests in mice showed that the minimum lethal dose of the host bacterium SE-21 was 5×10^(8) CFU/mL,and the survival rate of infected mice treated with vB_SalP_QS(100μL 1×10^(7) PFU/mL)and vB_SalP_SE29(100μL 1×10^(7) PFU/mL)was 100%.The survival rate of mice in the vB_SalP_QS treatment group(200μL 1×10^(7) PFU/mL)was 80%.The survival rate of mice in the vB_SalP_SE29 treatment group(200μL 1×10^(7) PFU/mL)was 70%.All control mice died.5)Pathological observations showed that mixed phage could effectively kill Salmonella SE-21 and also better protect the intestinal villi of mice,which could significantly improve the survival rate of mice infected with SE-21.In conclusion,phage vB_SalP_QS has good acid-base,thermal stability as well as safety,and the therapeutic effect of mixed phage combination therapy is higher than that of phage monotherapy.This study provides an important experimental ba

关 键 词：沙门菌 混合噬菌体 全基因组测序 生物学特性 治疗效果 

分 类 号：S85[农业科学—兽医学]