肺炎克雷伯菌噬菌体的分离和生物学特性

Isolation and Characterization of Bacteriophage for Klebsiella pneumoniae

目的以临床分离的肺炎克雷伯菌肺炎亚种为指示菌,从污水中分离出该菌的噬菌体,并对其基本生物学特性进行研究。方法以双层琼脂法从污水中分离噬菌体,电镜观察噬菌体颗粒,紫外线诱导和丝裂霉素C诱导法鉴定是否属于溶原性噬菌体,进行一步生长实验和最佳感染复数的测定,双层琼脂法测定宿主谱。结果从污水中分离出肺炎克雷伯菌肺炎亚种的噬菌体1株,电镜下该噬菌体头部直径约为180 nm,尾长约210 nm;噬斑透明,直径4-7 mm;最佳感染复数为4;一步生长曲线显示潜伏期为35 min,裂解期为40 min,裂解量为94 PFU/细胞。结论该噬菌体属长尾噬菌体科,是裂解性噬菌体,宿主谱较窄,仅对部分肺炎克雷伯菌肺炎亚种和少量大肠埃希菌敏感。

óBJECTIVE To characterize bacteriophage isolated from sewage with indicator of Klebsiella pneumoniae subsp pneumoniae. METHODS Bacteriophage was isolated from sewage by double-layer agar plate method, identified lytic or lysogenic capacity by induced methods of ultraviolet ray and mitomycin C, performed one-step growth experiments, decided the optimal multiplicity of infection, and its structure was observed with electron microscope. RESULTS The study found a strain of bacteriophage against the K. pneumoniae subsp pneumoniae. The phage had a head of 180 nm in diameter and a tail of 210 nm in length. The plaque was transparent and 4-7 mm in diameter, the optimal multiplicity of infection was 4, latent period was 35 min and burst period was 40 min, the average burst size was about 94 PFU/cell. CONCLUSIONS The isolated bacteriophage belongs to Stylovinidae, and it is a lytic bacteriophage with narrow host spectrum. Moreover, it is only sensitive to a part of K. pneumoniae subsp pneumoniae and a few of Escherichia coli strains.