title: Development of a simple and sensitive fluorimetric method for isolation of coumaphos-hydrolysing bacteria.
abstract: OBJECTIVE
  To develop a simple, rapid and sensitive fluorimetric assay to detect, isolate and characterize a soil bacterium capable of degrading the organophosphorus pesticide, coumaphos.
  
  
  RESULTS
  A high throughput microtitre plate-based method was used to quantify coumaphos hydrolysis by the bacterium. The fluorescent hydrolysis product of coumaphos, chlorferon, was detected at levels as low as 10 nmol l(-1). Incorporation of coumaphos into agar plates allowed the rapid detection of coumaphos-hydrolysing bacteria when exposed to an excitation wavelength of approximately 340 nm. The coumaphos-hydrolysing enzyme could be visualized when bacterial cell extracts were separated on SDS-PAGE, incubated with coumaphos and exposed to an excitation source as above.
  
  
  CONCLUSIONS
  This method is 100-fold more sensitive than the currently used spectrophotometric method for coumaphos.
  
  
  CONCLUSIONS
  This is a unique and versatile tool to screen for bacteria possessing phosphotriesterase activity.
authors.affiliation: Commonwealth Scientific and Industrial Research Organization (CSIRO) Entomology, GPO Box 1700, Canberra, ACT 2601, Australia.
authors.forename: R L
authors.initials: RL
authors.lastname: Harcourt
authors.forename: I
authors.initials: I
authors.lastname: Horne
authors.forename: T D
authors.initials: TD
authors.lastname: Sutherland
authors.forename: B D
authors.initials: BD
authors.lastname: Hammock
authors.forename: R J
authors.initials: RJ
authors.lastname: Russell
authors.forename: J G
authors.initials: JG
authors.lastname: Oakeshott
mesh_terms: D001419:Bacteria / Q000201:enzymology* / Q000302:isolation & purification*; D003372:Coumaphos / Q000378:metabolism*; D005470:Fluorometry / Q000379:methods*; D007306:Insecticides / Q000378:metabolism*; D012680:Sensitivity and Specificity; D012988:Soil Microbiology; D014468:Umbelliferones / Q000737:chemistry
chemical_list: D007306:Insecticides; D014468:Umbelliferones; C305311:chlorferron; D003372:Coumaphos