Characterization of Vibrio harveyi Bacteriophages Isolated from Aquaculture Tanks

Twelve bacteriophage strains of Vibrio harveyi were isolated from sea water samples obtained from aquaculture tanks. Two phage strains infected one bacterial strain and the other showed broad host ranges. These bacteriophage strains were divided into five groups based on their host ranges. Four representative strains, <f>H17-5c, <f>H17-7b, <f>H17-8b and <f>H17-9b which infect Vibrio harveyi ATCC 14126, were selected and characterized according to various tests such as heat stability, chloroform stability, adsorption rate to V. harveyi ATCC 14126, and one-step growth experiment. Phage strains, <f>H17-5c, <f>H17-7b and <f>H17-8b were inactivated completely with heat treatment over 60ｰC for 10 min. Adsorption rates of these strains to host cells were approximately 70%. On the other hand, <f>H17-9b was inactivated at around 45ｰC and the adsorption rate is approximately 25%. One-step growth experiments indicated that the latent period and burst size at 25ｰC of <f>H17-5c, <f>H17-7b, <f>H17-8b and <f>H17-9b strains were 70 min and 5.4, 35 min and 100, 40 min and 170, and 50 min and 5.5, respectively