Summary Microbial mats are highly structured and diverse communities, and one of the earliest‐known life assemblages. Mat bacteria interact within an environment marked by strong geochemical gradients and fluctuations. We examined natural mat systems for the presence of autoinducers involved in quorum sensing, a form of cell–cell communication. Our results revealed that a diverse array of N ‐acylhomoserine lactones (AHLs) incl...

Microbial communities often produce copious films of extracellular polymeric secretions (EPS) that may interact with sediments to influence spectral reflectance signatures of shallow marine sediments. We examined EPS associated with microbial mats to determine their potential effects on sediment reflectance properties. Distinct changes in spectral reflectance signatures of carbonate sediments from the Bahamas were observed amo...

We conducted experiments to determine effects of particle type on assimilatory metal bioavailability to Leptocheirus plumulosus, an infaunal, estuarine amphipod that is commonly used in sediment toxicity tests. The following particles were used to represent natural food items encountered by this surface‐deposit and suspension‐feeding amphipod: bacterial exopolymeric sediment coatings, polymeric coatings made from Spartina alte...

Waterborne chemical cues are critical in mediating interactions among marine organisms, yet mechanisms controlling the extinction of these signals have not been described. Exogenous factors, such as uptake by bacteria or adsorption to suspended clays or biofilms, could influence the concentrations of environmental signal molecules. In this study, we chose glycyl‐glycyl‐L‐arginine (GGR) to examine the rates and mechanisms of pe...