Characterization of ZZ2,a lytic bacteriophage that infects clinical isolates of Acinetobacter baumannii

Objective To characterize ZZ2,aphage that infects clinical isolates of Acinetobacter baumannii. Methods The morphology of the phage ZZ2was observed with electron microscopy,and its one-step growth curve,host range,and stability were determined. Results The phage ZZ2 exhibited lytic activity evident in clear areas on the bacterial lawns of3 A.baumannii strains,AB09V,AB0901,and AB0904.Of the three strains,AB09V was the most sensitive to the phage.Morphologically,ZZ2 was classified as a member of the Myoviridae family and the Caudovirales order.The phage is highly infectious with a short latent period(12min)and a large burst size(191±5PFU/cell),and the phage is stable over a wide pH range(4to 9)and at extreme temperatures(between 50℃and 60℃). Conclusion The characteristics of the phage ZZ2 greatly increase its utility as a biological bactericide.