以40株鸡致病性大肠杆菌为作用对象分析噬菌体Bp7的裂解谱，并用透射电镜较系统地观察分析噬菌体Bp7侵染并裂解大肠杆菌的过程。结果显示，噬菌体Bp7可裂解40株鸡致病性大肠杆菌中的14株，裂解率达35％。噬菌体Bp7头部外廓呈六边形，平均直径约93nm，尾长约106nm，有尾鞘；噬菌体Bp7通过尾丝吸附于杆状的大肠杆菌上。噬菌体Bp7侵染大肠杆菌后30min时处于隐蔽期，45min时处于成熟阶段，60min时已经进入释放期，一个溶菌周期大约为60min。本研究为噬菌体作为抗生素替代品治疗细菌病的研究提供了理论基础。

The aim is to observe and analyze the infection process of E.coli by bacteriophag Bp7 systematically by TEM and its lysis spectrum. The results show that, Bp7 can lyse 14 in 40 strains of E.coli and its lysis rate is 35%. Bp7 has a hexagonal head with diameter of 93nm and connected with a flexible tail which mean length is 106nm. The tail has tail sheath. Bp7 adsorbed on the rod-shaped E.coli via its tail wire. In the first 30min, the infection is in the hidden phase, and maturity phase appears at 45mpi (minute post infection), release period is at 60mpi, and a lytic cycle is about 60min. This study provides a theoretical basis for bacteriophag as an alternative to antibiotics in the treatment of bacterial diseases.