阪崎肠杆菌噬菌体的分离及其生物学特性

目的]以阪崎肠杆菌模式菌株及分离菌株为指示菌,从污水中分离出该菌噬菌体,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,通过同属和同科参考菌株测定噬菌体的特异性和宿主谱;电镜观察噬菌体颗粒形态;随机扩增多态性DNA(RAPD)实验分析噬菌体的分子生物学特性.结果]从污水中分离得到5株噬菌体,表现出较窄的宿主范围,仅裂解阪崎肠杆菌,以ATCC 51329分离的噬菌体SK2可裂解27株阪崎肠杆菌中的24株(89%),负染经电镜观察,5株噬菌体都是由多面体头部和尾部组成;随机引物(5′-GAAACGGGTG-3′)扩增DNA分析,5株噬菌体DNA明显不同.结论]分离出的5株噬菌体仅对阪崎肠杆菌敏感,在阪崎肠杆菌的分型、预防、治疗、以及生态环境的净化等方面具有潜在用途.

Isolation and characterization of bacteriophages of Enterobacter sakazakii

Objective] To isolate bacteriophage of Enterobacter sakazaki from sewage using reference and isolated strains as indicators, and to observe the biological characteristics of the bacteriophage. Methods] Bacteriophages were isolated from sewage with double layer agar. Specificity and host ranges of the bacteriophages were determined by reference bac-terium from same genus and family. Phage particles were observed by electron microscope and its molecular character was analyzed by Random amplified polymorphic DNA. Results] Five bacteriophages of E. sakazakii were isolated from sewage and showed relatively narrow host ranges, only E. sakazakii could be lysised. The phage SK2 isolated from ATCC 51329 could form plaques on 24 of all 27 E. sakazakii strains (89%). All five phage particles had the hexagonal heads and tails after observing with negatively stained method by electron microscope. Random amplified polymorphic DNA analy-sis showed the polymorphism of the five phages. Conclusion] E. sakazakii phages isolated from sewage were only sensi-tive to E. sakazakii, and had potential usage in typing, preventing, treating E. sakazakii and entironment protection.