# Isolation and characterization of a novel bacteriophage ST1749 and its effectiveness against Vibrio parahaemolyticus and Salmonella spp

## TL;DR

A new bacteriophage called ST1749 was isolated and shown to effectively kill Vibrio and Salmonella bacteria, with potential use as a biocontrol agent.

## Contribution

A novel lytic bacteriophage ST1749 is isolated and characterized for its broad antibacterial activity and stability.

## Key findings

- Phage ST1749 effectively lyses Vibrio parahaemolyticus and Salmonella spp.
- It significantly reduces biofilm formation in vitro.
- The phage is stable across a wide range of temperatures and pH levels.

## Abstract

•Demonstrates vigorous lytic activity against the genera Vibrio and Salmonella.•Significantly reduces biofilm in vitro assays.•Exhibits high stability across various temperatures and pH levels.•ST1749 produced 117, 176, and 52 PFU per host cell against V. parahaemolyticus, Salmonella enteritidis, and Salmonella typhimurium, respectively.

Demonstrates vigorous lytic activity against the genera Vibrio and Salmonella.

Significantly reduces biofilm in vitro assays.

Exhibits high stability across various temperatures and pH levels.

ST1749 produced 117, 176, and 52 PFU per host cell against V. parahaemolyticus, Salmonella enteritidis, and Salmonella typhimurium, respectively.

Bacteriophages are extensively employed across various fields, including medicine, veterinary medicine, the food industry, agriculture, biotechnology, and pharmacy, owing to their numerous advantages. These advantages include rapid clearance of pathogens, self-propagation at the infection site, host specificity, potential for genetic modification, ease of isolation, stability, and low production costs. This study isolated a bacteriophage from shrimp pond wastewater in the Mekong Delta region. The bacteriophage was identified as a lytic bacteriophage belonging to the genus Bruyoghevirus, class Caudoviricetes, with the ability to effectively lyse three bacterial strains: V. parahaemolyticus, Salmonella enteritidis, and Salmonella typhimurium. Growth curve analysis revealed variations in the latency period and the number of phages produced during the life cycle across all three hosts. Bacteriophage Produced 117, 176, and 52 PFU/cell against V. parahaemolyticus, S. enteritidis, and S. typhimurium, respectively. Phage ST1749 demonstrated activity across a broad range of temperatures (-20 °C to 70 °C) and pH levels (2 to 10), with optimal stability observed at pH 5 to 7. Furthermore, phage ST1749 exhibited biofilm-degrading and lytic capabilities against the three bacterial strains studied. These findings suggest that phage ST1749 has the potential to serve as a biocontrol agent for treating infections caused by antibiotic-resistant bacteria.