Abstract 1681 Investigating disruption of lysis inhibition in Vibrio cholerae as a bacterial defense mechanism

Vibrio cholerae, the causative agent of cholera disease, often exists at dynamic levels which leads to seasonal epidemics.With the rise of antibiotic resistance, phage therapy has emerged as a promising alternative treatment.This research focuses on the lysis proteins expressed in V. cholerae and its associated bacteriophage, ICP1.Bacteriophage ICP1 promotes lysis inhibition through its antiholin, ArrA, which suppresses lytic activity of the holin TeaA.As an evolutionary defense mechanism, lysis inhibition is disrupted by V. cholerae to prevent the virion offspring from infecting other bacterial cells.Upon ICP1 infection of V. cholerae, genetic element PLE1 excises from the bacterial chromosome and replicates by hijacking the phage replisome and outnumbering the number of new virions.A PLE1-encoded protein, LidI, is known to interrupt phage-mediated lysis inhibition.We used a Bacterial Adenylate Cyclase-Based Two-Hybrid (BACTH) assay to detect protein-protein interactions between LidI, TeaA and ArrA via co-transformation and spot assays.Additionally, we cloned four plasmids that enable the inducible expression of proteins, independent from the ICP1 phage.These plasmids facilitate in vivo assays to explore protein interactions and behaviors related to lysis inhibition.Our results suggest that the phage-encoded holin TeaA oligomerizes and interacts with the bacterial defense protein LidI.Our findings contribute to current research into phage-bacteria dynamics and the advancement of phage therapy as a sustainable approach to combating bacterial infections.