Effects of horizontal gene transfer on bacteriophage infectivity

Abstract

Bacterial infections and its treatment has been a concern for researchers and scientists for centuries. At first, the invention and treatment with antibiotics seemed like a promising and reliable solution to the problem. However, with an increasing bacterial population gaining antibiotic resistance through horizontal gene transfer, it is now crucial to find a replacement for antibiotic treatment against different bacteria. Bacteriophage therapy has been considered as a potential candidate for the substitution. Therefore, the objective of our study was to evaluate the potentiality of phage infectivity on different strains of a specific bacteria and on the same strains transformed with antibiotic resistant genes to consider the impact of horizontal gene transfer. We focused on 5 native infectious (O1) strains of Vibrio cholerae and 2 specific antibiotics: ampicillin and kanamycin. We also used another strain of Vibrio cholerae as the control for the experiment. We extracted ampicillin resistant gene containing pGLO plasmid from E. coli DH5alpha and kanamycin resistant gene containing chromosomal DNA from 1877 strain of Vibrio cholerae. Then transformed these genes into the 5 native strains separately to achieve the effect of horizontal gene transfer in vitro. As a result, we conducted the experiment on 16 strains of Vibrio: 5 native strains, 5 native strains transformed with ampicillin resistance gene, 5 native strains transformed with kanamycin resistance gene, and one control strain (1877 strain of Vibrio). Then we carried out a spot test on each of the strains with 6 phages from our lab stock and observed the result to detect any impact of the transformation (Horizontal gene transfer) on the infectivity of the phages.