Isolation and characterization of bacteriophages of Enterobacter sakazakii

Abstract:

[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.