Phage Endolysins as Potential Antimicrobials against Multidrug Resistant Vibrio alginolyticus and Vibrio parahaemolyticus: Current Status of Research and Challenges Ahead

Abstract

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.

Isolation and Characterization of the Novel Phages vB_VpS_BA3 and vB_VpS_CA8 for Lysing Vibrio parahaemolyticus

“…The one-step growth curve was generated according to a previous report with minor modifications (Yin et al, 2019). V. parahaemolyticus culture (5 mL) was incubated to OD 600 = 0.2 and the bacterial cell suspension was diluted to 1.0 × 10 8 cfu/mL.…”

Isolation and Characterization of Salmonella Jumbo-Phage pSal-SNUABM-04

“…Of bacterial cell wall lysis genes, lytic glycosylase (ORF 200), extracellular polysaccharide (EPS) depolymerase, i.e., pectate lysate, (ORF 139) and N-acetylmuramidase (ORF 158), tail-associated lysozyme, i.e., fused to tape measure protein, (ORF 243) protein genes were identified. Phage-encoded enzymes attacking peptidoglycans were studied in many previous studies [ 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 ]. These enzymes have their distinct attack points which are linkage points between tetrapeptides and residues.…”

A Hundred Years of Bacteriophages: Can Phages Replace Antibiotics in Agriculture and Aquaculture?

“…Numerous in vitro assays testing the effect of phage therapy on fish pathogenic bacteria have been carried out over the last two decades; in addition, a number of in vivo studies have also evaluated the potential of bacteriophages for controlling bacterial infections in aquaculture. These studies include the use of phages to effectively combat multidrug resistant bacteria [103,104]. A selection of some of the most relevant studies on the characterization and/or the efficacy (in vitro and/or in the field) of phages from different families against a wide range of pathogens that cause a variety of disease in many fish and shellfish species are shown in Table 2.…”

“…As is the case for the resistance to antimicrobial agents, this problem can be prevented or resolved by the use of different strategies. These include applying cocktails containing not just a single phage but a mixture of three to five different phages [36,151] and the use of phage endolysins [8,104] in order to prevent the appearance of resistance during phage treatments. Bacterial resistance to phages usually appears at a rate between 10 −6 and 10 −8 .…”