title: Lux-biosensor assessment of pH effects on microbial sorption and toxicity of chlorophenols.
abstract: Lux-marked bacterial biosensors and a commercial toxicity testing bacterial strain (Microtox) were exposed to 2,4-dichlorophenol (DCP) and the light output response measured. Increasing DCP concentrations caused a decrease in light output in all three biosensors with an order of sensitivity (in terms of luminescence decrease over the DCP concentration range) of Pseudomonas fluorescens < Escherichia coli < Microtox. Adsorption of DCP to E. coli was measured using uniformly ring labelled [14C]DCP and found to be very rapid. The effect of pH on toxicity and adsorption was also investigated. Low pH values increased the amount of DCP adsorbed to the cell and increased the toxicity of DCP.
authors.affiliation: Department of Plant and Soil Science, University of Aberdeen, UK. g.m.sinclair@abdn.ac.uk
authors.forename: G M
authors.initials: GM
authors.lastname: Sinclair
authors.forename: G I
authors.initials: GI
authors.lastname: Paton
authors.forename: A A
authors.initials: AA
authors.lastname: Meharg
authors.forename: K
authors.initials: K
authors.lastname: Killham
mesh_terms: D000327:Adsorption; D015374:Biosensing Techniques; D002462:Cell Membrane / Q000378:metabolism; D002733:Chlorophenols / Q000378:metabolism* / Q000633:toxicity*; D004926:Escherichia coli / Q000187:drug effects / Q000502:physiology; D006863:Hydrogen-Ion Concentration; D008163:Luminescent Measurements; D011551:Pseudomonas fluorescens / Q000187:drug effects / Q000502:physiology; D011933:Reagent Kits, Diagnostic; D018675:Toxicity Tests
chemical_list: D002733:Chlorophenols; D011933:Reagent Kits, Diagnostic; C004762:2,4-dichlorophenol