Understanding phage BX-1 resistance in AP-1 and the role of quorum-sensing regulation.

The marine ecosystem is characterized by a rich diversity of bacterial hosts and their phages. The propagation of phages is primarily limited by their ability to adsorb to host cells and is further challenged by various bacterial defense mechanisms. To fully realize the potential of phage therapy in aquaculture, a comprehensive understanding of phage-host interactions and their regulation is essential.

Design, Screening, and Characterization of Engineered Phage Endolysins with Extracellular Antibacterial Activity against Gram-Negative Bacteria.

Phage-encoded endolysins are emerging antibacterial agents based on their ability to efficiently degrade peptidoglycan on Gram-positive bacteria, but the envelope characteristics of Gram-negative bacteria limit their application. Engineering modifications of endolysins can improve the optimization of their penetrative and antibacterial properties. This study constructed a screening platform to screen for engineered Artificial-Bp7e (Art-Bp7e) endolysins with extracellular antibacterial activity against Escherichia coli.

A Novel Polyvalent Bacteriophage vB_EcoM_swi3 Infects Pathogenic and .

A novel virulent bacteriophage vB_EcoM_swi3 (swi3), isolated from swine feces, lyzed 9% (6/65) of and isolates 54% (39/72) of isolates, which were all clinically pathogenic multidrug-resistant strains. Morphological observation showed that phage swi3 belonged to the family with an icosahedral head (80 nm in diameter) and a contractile sheathed tail (120 nm in length). At the optimal multiplicity of infection of 1, the one-step growth analysis of swi3 showed a 25-min latent period with a burst size of 25-plaque-forming units (PFU)/infected cell.

Characterization of a Novel Bacteriophage swi2 Harboring Two Lysins Can Naturally Lyse .

The novel virulent bacteriophage swi2 was isolated from a pig farm, and its biological characteristics, genome architecture, and infection-related properties were characterized. Phage swi2 has a high titer of 1.01 × 10 PFU/mL with good tolerance to UV rays and remains stable in the pH range of 6-10 and at temperatures less than 50°C.