本研究旨在通过分离粪肠球菌裂解性噬菌体并分析其生物学特性，为噬菌体疗法应用于肠球菌感染提供依据。以粪肠球菌为宿主菌，用双层琼脂法从环境污水中分离出1株裂解性噬菌体(命名为φEn-­ZZ8)，对其生物学特性进行初步分析。透射电镜观察发现，φEn­-ZZ8头部呈二十面体立体对称，直径约40 nm；尾部呈丝状，长约200 nm。吸附实验表明，在10 min内超过90%的噬菌体可吸附至宿主菌细胞。一步生长曲线显示，φEn­-ZZ8的潜伏期为15 min，爆发期为40 min，爆发量为150 pfu/cell。φEn­-ZZ8基因组对内切酶Hind Ⅲ、EcoR Ⅴ、NdeⅠ、PstⅠ、XbaⅠ和SacⅡ敏感；基因组大小约为42 kb。十二烷基硫酸钠­聚丙烯酰胺凝胶电泳至少可见14条蛋白带，相对分子质量为10 000～130 000。φEn­-ZZ8对26株粪肠球菌的裂解率达30.8%，其裂解活性在pH 5～8和50～70 ℃条件下仍稳定。结果提示，φEn­-ZZ8是一种裂解性强、裂解谱较宽、对温度具有耐受性的裂解性噬菌体，有望成为抗耐药性肠球菌感染的噬菌体生物制剂。

This study aims to isolate lytic bacteriophages from Enterococcus faecalis (E. faecalis)，analyze its biological characteristics and to establish the research basis for a phage­based therapy against Enterococcus infections. A lytic bacteriophage (named φEn­-ZZ8) was isolated from the sewage using double­agar method and its basic biological characteristics were analyzed. The results showed that φEn­-ZZ8 had an icosahedral head of 40 nm in diameter and a filamentous tail of 200 nm in length. The adsorption rate of φEn-­ZZ8 reached 90% in 10 min. One­step growth showed that φEn­-ZZ8 had a short latency period of 15 min, a rise period of 40 min, and a burst size of 150 pfu/cell. The genome of φEn­-ZZ8 was sensitive to HindIII, EcoRV, NdeI, PstI, Xba I and Sac II, and the size of the genome was estimated to be 42 kb. Sodium dodecyl sulfate­polyacrylamide gel electrophoresis (SDS­-PAGE) revealed that at least 14 proteins were observed on the gel, ranging from 11 000 to 130 000. The bacteriophage specifically infected and lysed 30.8% E. faecalis isolates. The φEn­-ZZ8 also exhibited stability to the wide range of pH and temperature. The data suggest that phage φEn-­ZZ8 may be a candidate therapeutic agent to control Enterococcus infections.