病毒学报

分离鸡白痢沙门氏菌及其噬菌体,对分离到的噬菌体进行生物学特性分析。采用沙门氏菌选择性培养基进行鸡白痢沙门氏菌的分离,并进行特异性PCR鉴定。以鸡白痢沙门氏菌分离株为宿主菌,采用双层平板法进行噬菌体的分离,通过负染法电镜观察噬菌体的形态和大小,并对噬菌体进行裂解谱、最佳MOI、一步生长曲线、对温度、pH、紫外线以及氯仿的稳定性等生物学特性的研究。分离到噬菌体vB-SpuS-Spp4为长尾噬菌体,对29株鸡白痢沙门氏菌的裂解率为100%;最佳感染复数为0.001时噬菌体的效价可达1.47×109 PFU/mL。该噬菌体潜伏期为15min,暴发期为45min,暴发量为127;vB-SpuS-Spp4温度耐受性较强,在pH2~13环境中仍有活性。噬菌体vB-SpuS-Spp4对紫外照射不敏感,对氯仿不敏感。噬菌体vB-SpuS-Spp4作为一株烈性噬菌体,对鸡白痢沙门氏菌具有广泛的裂解作用,为临床鸡白痢的噬菌体控制奠定了基础。

We wished to isolate Salmonella pullorum and its bacteriophages and analyze the biological characteristics of the latter.Salmonella pullorumstrains were isolated on Salmonella-selective media and identified by specific polymerase chain reaction.Salmonella pullorumisolates were used as host bacteria,and bacteriophages isolated by the double-layer plate method.The morphology and size of bacteriophages were observed by negative-staining electron microscopy.The host spectrum,optimal multiplicity of infection(MOI)and one-step growth curve of the phage were obtained.Stabilities of the phage against temperature,pH,ultraviolet light and chloroform were also studied.The bacteriophage vB-SpuS-Spp4 could lyse all of the 29 tested strains of Salmonella pullorum.The optimal MOI was 0.001 and the bacteriophage titer was up to 1.47×109 PFU/mL.The one-step growth curve demonstrated that the incubation period of bacteriophageswas 15 min,burst period was 45 min,and burst size was 127.The temperature tolerance of vB-SpuS-Spp4 was strong,and it was active in the pH range 2~13.vB-SpuS-Spp4 was not insensitive to ultraviolet radiation or and chloroform.Bacteriophage vB-SpuS-Spp4,as a potent antimicrobial,had a wide-spectrum lytic activity against Salmonella pullorum.This study lays the foundation for the clinical application of bacteriophages for the Salmonella pullorum infection.