title: Novel detection of Escherichia coli beta-D-glucuronidase activity using a microbially-modified glassy carbon electrode and its potential for faecal pollution monitoring.
abstract: The electrochemical detection of Escherichia coli beta-D-glucuronidase activity as a means of monitoring water pollution by faecal material was investigated using separate Moraxella- and Pseudomonas putida-modified glassy carbon electrodes. The former was more sensitive and selective. The Moraxella-modified biosensor was 100 times more rapid and sensitive than the spectrophotometric detection of beta-D-glucuronidase activity. The experimental limit of detection of the biosensor was two c.f.u. per 100 ml polluted water sample within 20 min. The biosensor gave a linear response to commercial beta-D-glucuronidase concentration between 0.2 ng and 2 microg ml(-1). The biosensor detected activity of beta-D-glucuronidase from viable but non-culturable (VBNC) cells and can therefore serve as a presence or absence device for rapid water quality monitoring.
authors.affiliation: Department of Biochemistry, Rhodes University, Grahamstown, South Africa.
authors.forename: Chamunorwa Aloius
authors.initials: CA
authors.lastname: Togo
authors.forename: Victor Collins
authors.initials: VC
authors.lastname: Wutor
authors.forename: Janice Leigh
authors.initials: JL
authors.lastname: Limson
authors.forename: Brett Ivan
authors.initials: BI
authors.lastname: Pletschke
mesh_terms: D001681:Biological Assay / Q000295:instrumentation*; D015374:Biosensing Techniques / Q000295:instrumentation*; D002244:Carbon / Q000737:chemistry; D004784:Environmental Monitoring / Q000295:instrumentation*; D004789:Enzyme Activation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D004926:Escherichia coli / Q000201:enzymology* / Q000302:isolation & purification*; D005243:Feces / Q000382:microbiology*; D005966:Glucuronidase / Q000032:analysis* / Q000737:chemistry; D008839:Microelectrodes; D009016:Moraxella / Q000378:metabolism; D011549:Pseudomonas / Q000378:metabolism; D014871:Water Microbiology; D014873:Water Pollutants / Q000032:analysis
chemical_list: D014873:Water Pollutants; D002244:Carbon; D005966:Glucuronidase