Isolation, Characterization, and Application of a Novel Vibrio parahaemolyticus Bacteriophage from Retail Shrimp in Sarawak, Malaysia

Shrimp farming, a highly profitable sector in global aquaculture, has seen remarkable growth in recent years. This increasing demand and the expansion of farming operations, including in Sarawak, Malaysia, highlight the sector's potential. However, the industry faces significant challenges, particularly the prevalence of vibriosis, a bacterial infection caused by Vibrio species. Contamination of food products has also increased the risk of vibriosis in humans. The widespread use of antibiotics to combat this disease has led to the rapid emergence of antimicrobial resistance (AMR) bacteria. This study specifically focuses on the isolation and characterization of phage EniLVP02, a novel bacteriophage with the potential to combat V. parahaemolyticus infections. EniLVP02 was successfully isolated from shrimp purchased at a retail market and exhibited strong lytic activity against V. parahaemolyticus strains. Structural analysis categorized EniLVP02 within the Straboviridae family, belonging to the class Caudoviricetes. The phage displayed a narrow host range and lytic nature only towards V. parahaemolyticus strains isolated from the Telaga Air shrimp farm. Phage EniLVP02 exhibited long latent period of 120 minutes and large burst size of 144 phages per infected cells. Stability studies revealed EniLVP02's resilience across various pH (pH 4.0 - 9.0) and temperature (28 °C - 65 °C) conditions, particularly at physiological temperatures. Comparative genome analyses indicated its distinct evolutionary relationship and low homology with other Vibriophages, suggesting its novelty. EniLVP02 demonstrated significant potential in biofilm prevention and destruction, with absorbance (OD600 nm) reduction from 0.592 0.055 to 0.204 0.016 and from 0.843 0.003 to 0.174 0.026 respectively. Moreover, in the treatment of V. parahaemolyticus-contaminated shrimp meat, EniLVP02 effectively inhibit bacterial concentrations by 75.2% at room temperature and 16.2% at 4 °C after 24 hours. Genomic sequencing revealed low similarity between EniLVP02 with other phages, suggesting its novelty. Importantly, the absence of lysogeny-related, antibiotic resistance, and virulence genes in its genome supports EniLVP02's safety for therapeutic use. This study underscores the importance of exploring phages from retail food products for therapeutic applications and highlights the promising attributes of phage EniLVP02 in combating V. parahaemolyticus infections in aquaculture. Further investigations on its compatibility with other phages and application in diverse food matrices are warranted to assess its full potential.