Insights Into Arsenite and Arsenate Uptake Pathways Using a Whole Cell Biosensor.

摘要: Despite its high toxicity and widespread occurrence in many parts of the world, arsenic (As) concentrations decentralized water supplies such as domestic wells remain often unquantified. One limitation to effective monitoring is cost lack portability current speciation techniques. Here, we present an biosensor assay capable quantifying determining bioavailable fraction species at environmentally relevant concentrations. First, found that inorganic phosphate, a buffering agent nutrient commonly most bioassay exposure media, was fact limiting As(V) uptake, possibly explaining variability detection reported so far. Second, show nature carbon source used differentially affects response As(III). Finally, our data support existence non-specific reduction pathways (non ars encoded) are responsible for As(III), allowing by biosensor. To validate laboratory approach using field samples, performed As(III) standard additions on natural samples collected from 17 lakes surrounding Giant Mine Yellowknife, Canada. We legacy contamination these lake accurately quantified Interestingly, bioavailability freshly added standards showed signs matrix interference, indicative dynamic interactions between / environmental constituents have yet be identified. Our results point towards dissolved organic controlling interactions, thus, As bioavailability.