title: The use of a genetically engineered Pseudomonas species (Shk1) as a bioluminescent reporter for heavy metal toxicity screening in wastewater treatment plant influent.
abstract: Heavy metals are known to be inhibitory and toxic to the activated-sludge microbial community in biological wastewater treatment plants. Toxicity screening of aqueous mixtures of these heavy metal ions in plant influent could use both chemical and biological methods. As a biological method, luminescent bacterial bioreporters offer the advantages of a simple test procedure and rapid response. Current biologically based methods for screening aqueous streams for toxicity are labor-intensive, inaccurate, or difficult to use in continuous monitoring applications. In the present study, a system was developed that is simple and easily automated. This system is based on the bacterium Shk1, a genetically engineered bioluminescent Pseudomonad whose parent strain was originally isolated from activated sludge. Compared with other bioluminescence-based systems (specifically, the Microtox assay), the system of the present study more accurately reflects the effects of the toxicity of common metal ions on activated-sludge respirometry without being overly sensitive to typical constituents of wastewater. The use of Shk1 as a bioluminescent reporter for heavy metal toxicity testing for the application of wastewater treatment influent toxicity screening is presented in this study.
authors.affiliation: Department of Chemical Engineering, University of Tennessee, Knoxville 37996-2200, USA.
authors.forename: Shijin
authors.initials: S
authors.lastname: Ren
authors.forename: Paul D
authors.initials: PD
authors.lastname: Frymier
mesh_terms: D001681:Biological Assay / Q000379:methods; D004784:Environmental Monitoring / Q000379:methods*; D005818:Genetic Engineering; D008163:Luminescent Measurements; D019216:Metals, Heavy / Q000633:toxicity*; D011549:Pseudomonas / Q000187:drug effects* / Q000235:genetics / Q000502:physiology*; D012680:Sensitivity and Specificity; D012722:Sewage / Q000737:chemistry*; D014865:Waste Disposal, Fluid
chemical_list: D019216:Metals, Heavy; D012722:Sewage