RESUMEN
A pathogen of significance in the aquaculture sector, the Gram-negative marine bacterium Vibrio parahaemolyticus causes gastroenteritis associated with consumption of improperly prepared seafood. This bacterium can be controlled using lytic bacteriophages as an alternative to antibiotics. ÏVP-1 is a lytic phage of V. parahaemolyticus that was isolated from an aquafarm water sample with the aim of assessing its potential as a bio-control agent and determining its physicochemical properties and genomic sequence. Morphological analysis by transmission electron microscopy and phylogenetic analysis based on the large terminase subunit gene showed that this phage belongs to the family Myoviridae. It could infect multiple-drug-resistant (MDR) V. parahaemolyticus and V. alginolyticus strains of mangrove and seafood origin. With a maximum adsorption time of 30 min, ÏVP-1 has a short latent period of 10 min with burst size of 44 particles/cell. Whole-genome sequencing was done using the Illumina platform, and annotation was done using GeneMarkS and Prodigal. The 150,764bp genome with an overall G+C content of 41.84% had 203 putative protein-encoding open reading frames, one tRNA gene, and 66 predicted promoters. A number of putative DNA replication and regulation, DNA packaging and structure, and host lysis genes were identified. Comparison of the ÏVP-1 genome sequence to those of known Vibrio phages indicated little discernible DNA sequence similarity, suggesting that ÏVP-1 is a novel Vibrio phage. Sequence analysis revealed the presence of 64 potential ORFs with a T4-like genomic organization. In silico analysis suggested an obligate lytic life cycle and showed the absence of lysogeny or virulence genes. The complete sequence of ÏVP-1 was annotated and deposited in the GenBank database (accession no. MH363700). The genetic features of this novel phage suggest that it might be applicable for phage therapy against pathogenic strains of V. parahaemolyticus.
Asunto(s)
Bacteriófagos/genética , Resistencia a Múltiples Medicamentos/genética , Genoma Viral/genética , Myoviridae/genética , Vibrio parahaemolyticus/virología , Acuicultura/métodos , Composición de Base/genética , Biopelículas , Genómica/métodos , Sistemas de Lectura Abierta/genética , Terapia de Fagos/métodos , FilogeniaRESUMEN
Vibrio alginolyticus and V. parahaemolyticus, the causative agents of Vibriosis in marine vertebrates and invertebrates, are also responsible for fatal illnesses such as gastroenteritis, septicemia, and necrotizing fasciitis in humans via the ingestion of contaminated seafood. Aquaculture farmers often rely on extensive prophylactic use of antibiotics in farmed fish to mitigate Vibrios and their biofilms. This has been postulated as being of serious concern in the escalation of antibiotic resistant Vibrios. For this reason, alternative strategies to combat aquaculture pathogens are in high demand. Bacteriophage-derived lytic enzymes and proteins are of interest to the scientific community as promising tools with which to diminish our dependency on antibiotics. Lysqdvp001 is the best-characterized endolysin with lytic activity against multiple species of Vibrios. Various homologues of Vibrio phage endolysins have also been studied for their antibacterial potential. These novel endolysins are the major focus of this mini review.
