Pseudomonas helleri噬菌体PrH-181的分离及生物特性分析

Isolation and biological characterization of Pseudomonas helleri bacteriophages PrH-181

Pseudomonas helleri为水产品冷藏过程中的优势腐败菌。为筛选得到能裂解Pseudomonas helleri的烈性噬菌体,采用双层平板法,从采集自不同省份的70个污水和土壤样品中,分离纯化得到了1株裂解活性较强的噬菌体PrH-181。形态学和生化特征实验结果显示,该噬菌体壳体为无尾二十面体结构,对氯仿不敏感,且核酸类型鉴定为RNA。根据ICTV对病毒的分类标准,PrH-181可鉴定为光滑病毒科噬菌体。该噬菌体最佳感染复数(MOI)为0.01,一步生长曲线显示其潜伏期为20 min,爆发期为180 min,裂解量为584。该噬菌体的耐热性良好;最佳生长pH为6.0~7.0,在pH6.0~9.0时其存活率可高达94.1%~98.8%,耐碱力较耐酸力强。

Pseudomonas helleri is dominant spoilage organism of aquatic products in the process of refrigeration. This study was isolated and purified a virulent phage, PrH-181 against Pseudomonas helleri from 70 sewage samples and soil samples from different provinces by double-plate method. The results of morphological and biochemical characteristics showed that the PrH-181 is icosahedral structure, not sensitive to chloroform, and the type of its nucleic acid is RNA. According to ICTV（International committee for taxonomy of viruses） classification for viruses, PrH-181 belongs to the Leviviridae family. The optimal MOI（Multiplicity of infection） of PrH-181 is 0.01. The one-step growth curve of PrH-181 showed that the latent period 20 min, the burst period 180 min, and the average burst size is 584 phageparticles/infected cell. The thermal stability of PrH-181 is poor. Its survival rate is 94.1%～98.8% in the range of pH 6.0～9.0 and its optimal pH is 6.0～7.0. PrH-181＇s alkaline tolerance is better than acidic tolerance.