I¦SP-3, a Salmonella-specific lytic phage capable of infecting its host under nutrient-deprived states

Salmonella is a robust pathogen capable of surviving under various hostile conditions. The ability of a Salmonella-specific lytic phage, I broken vertical bar SP-3, to infect its host under various nutrient-deprived conditions was studied. This phage was isolated from the intestinal contents of chicken. The identity of I broken vertical bar SP-3 was confirmed by sequence analysis whereby I broken vertical bar SP-3 showed maximum similarity towards T5-like phages of family Siphoviridae. The genome size of I broken vertical bar SP-3 was estimated to be 88.43 kb by pulsed-field gel electrophoresis (PFGE) analysis. I broken vertical bar SP-3 was able to infect its host under stationary phase, multiple nutrient-starved states, carbon-starved and nitrogen-starved conditions. I broken vertical bar SP-3 failed to multiply only under phosphate-starved condition. Host range studies revealed the genus specificity of I broken vertical bar SP-3. A wide host range within the genus and the capability of infecting bacterial host cells in ideal as well as nutrient-deprived conditions makes I broken vertical bar SP-3 a desirable candidate as a biocontrol agent.