A review of quorum-sensing and its role in mediating interkingdom interactions in the ocean.

Quorum sensing, first described in marine systems five decades ago, is a well-characterized chemical communication system used to coordinate bacterial gene expression and behavior; however, the impact of quorum sensing on interkingdom interactions has been vastly understudied. In this review, we examine how these molecules mediate communication between bacteria and marine eukaryotes; influencing processes such as development, disease pathogenesis, and microbiome regulation within marine ecosystems. We describe the varied mechanisms eukaryotes have evolved to interfere with bacterial quorum sensing signaling, the crucial role these signals play in host-virus interactions, and how their exchange may be governed by outer membrane vesicles, prevalent in marine systems. Here, we present a dynamic portrayal of the impact of quorum sensing signals beyond bacterial communication, laying the groundwork for future investigations on their roles in shaping marine ecosystem structure and function.