New toxicity determination method that uses fluorescent assay of Escherichia coli
Mariscal, A.; García, A.; Carnero, M.; Gómez, E.; Fernández-Crehuet, J.
Biotechniques 16(5): 888-893
1994
ISSN/ISBN: 0736-6205 PMID: 8068344 Document Number: 436665
We describe a new method that uses a fluorogenic bioassay of the beta-glucuronidase conversion of 4-methylumbelliferyl beta-D-glucuronide (MUG) to 4-methylumbelliferone to evaluate the individual toxic effects on Escherichia coli of Al-3+, Cr-6+, Hg-2+ and Li+. This work was designed to examine the effectiveness of this method to measure the effects of five ionic concentrations of either Al-3+, Cr-6+, Hg-2+ or Li+, on the growth of E. coli in a minimal medium that had MUG as the only source of carbon. This method was simple and fast, and its toxicity detection sensitivity was equal to, or greater than, existing bacterial bioassays. The use of the MUG substrate minimized the danger of interference by bacteria other than E. coli. Evaluations of toxicity in samples of public drinking water proved equally sensitive.