UNDERSTANDING THE PROCESS OF ORGANIC MATTER REMINERALIZATION AND ITS POSSIBLE LINK TO CYCLING OF CONTAMINANTS IN ESTUARIES

Malcolm X Shabazz (MXS) BioGeoChemistry Team in cooperation with the Reinfelder lab at Rutgers University and University of Tennessee researchers conducted primary field studies with estuarine water collected from Raritan Bay, New Jersey. Activities of three extracellular enzymes were measured in filtered (0.2µm) and non-filtered Raritan Bay water at two sites within the Raritan Bay estuary. These in-situ measurements were used to assess enzyme activity during high and low tide and proximity to the Raritan River. Filtered treatments were used to evaluate contributions of enzymes that are released into Raritan Bay water and those attached the cell. The “breakdown” of organic matter from the Raritan River by extracellular enzymes into sizes small enough for bacteria cells in surface waters is important for the marine carbon cycle and possibly contaminant biogeochemistry. Our research examines the role of enzymes such as leucine aminopeptidase (leu), α-glucosidase (alpha), and β-glucosidase (beta) using three fluorophore substrates on the carbon cycling in the Raritan Bay and the influence of organic matter remineralization on the bioavailability of contaminants in the Raritan Bay food web. The process of organic matter remineralization and its possible link to cycling of contaminants in estuaries is not well understood from an enzyme point of view.