Review of the Arbitrium (ARM) System: Molecular Mechanisms, Ecological Impacts, and Applications in Phage-Host...

Bacteriophages (phages) play a pivotal role in shaping microbial communities and driving bacterial evolution. Among the diverse mechanisms governing phage-host interactions, the Arbitrium (ARM) communication system represents a recently discovered paradigm in phage decision-making between the lytic and lysogenic cycles. Initially identified in Bacillus-infecting phages, the ARM system employs a quorum-sensing-like peptide signaling mechanism to modulate infection dynamics and optimize population-level survival strategies. Recent studies have elucidated the structural and functional basis of ARM regulation, highlighting its potential applications in antimicrobial therapy, microbiome engineering, and synthetic biology. The significance of ARM systems lies in their ability to regulate bacterial population stability and influence the evolutionary trajectories of microbial ecosystems. Despite being a relatively recent discovery, ARM systems have garnered considerable attention due to their role in decoding phage population dynamics at the molecular level and their promising biotechnological applications. This review synthesizes current advancements in understanding ARM systems, including their molecular mechanisms, ecological implications, and translational potential. By integrating recent findings, we provide a comprehensive framework to guide future research on phage-host communication and its potential for innovative therapeutic strategies.