Phage treatment of vibrio harveyi: A general concept of protection against bacterial infection

Abstract

The Vibrio harveyi (VH), called VH13-1, was isolated and collected from luminescent black tiger shrimp. To test the possibility for the use of permissive phage as a tool to treat the VH contamination in shrimp ponds, our new isolated temperate phage (VH-P) which is specific to the infection of VH13-1, was tested for its efficiency to kill the VH. Our study was conducted with the MOI (multiplicity of infection) of 1-100. The success of the treatment is determined if no VH bacterial colony is observed in the culture medium after the phage treatment. The MOI of 20 resulted in the killing of all the VH13-1 while MOI of 10 was inconsistent because two of the three experiments showed growth of bacterial colony and MOI of 1 resulted in significant survival of VH. These colonies were proved to become lysogenic infection of VH-P. The study shows that using temperate phage of VH-P to treat VH bacterium, it is necessary to treat with the sufficient amount of the VH-P phage at once. Insufficient amount of MOI will allow the VH to develop lysogenic infection and cause interference to super-infection to the same phage. Besides searching phage from natural sources as the subject to treat bacterial epidemic, genomic modification of phage genome is proposed to enhance the possibility for phage treatment to control the bacterium epidemic while drug resistance of the pathogenic bacteria is kept being developed but the new antibiotic can not be discovered. © 2011 Academic Journals Inc.