quorum sensing refers to the ability of bacteria to detect the presence of other bacteria using chemical cues and respond accordingly
cooperative interactions between bacteria allow them to coordinate beneficial group activities like biofilms
antagonistic interactions between bacteria allow them to exclude species that are detrimental to the community like antibiotic production
bacterial communities can be homo or hetero geneous
bacteria communicate with each other using chemical signals (quorum) such as AHL, AIP, or AI2
bacteria will form communities in high signal density areas
autoinducer 2 (AI2) are produced for interspecies communication between bacteria
AI2 is the most common quorum sensing molecule for interspecies communication made by LuxS signal synthase, chemical structure differs between aquatic (phosphosensor/phosphorelay, has boron) and terrestrial (similar to AHL, diffusion) bacteria
quorum sensing here is extrinsic (diffuses out then in), digital (all/nothing), autocrine/paracrine
