?ENHANCED DETECTION OF NITROFURANTOIN AS A MUTAGEN BY A MUTATOR R-PLASMID
Keywords:
Mutator R-plasmid, Enhanced detection, Nitrofurantoin.Abstract
Enhanced detection of nitrofurantoin as a chemical mutagen by a novel mutator R-plasmid pEB019 isolated Irorn
clinical stool specimen was investigated using Ames reverse mutation assay. Plasmid pEB019 protected E coli WP2
trp, WP2 trp (,lvrA, AB1157,AB1157uvrA tester strains against the bactericidal effects of nitrofurantoin. The mutage-
nicity assay results showed that there was no significant NFT-indueed reversion in E coli AB1157prototrophic strain
at all concentrations used. There was however, a significant (P < 0.0I) dose-related induced reversion mutation with
trains possessing R-plasmid pEB019 and pKM101, but with the former showing a greater activity compared with
pKM10I.Reversions in prototrophic and auxotrophic strains, bearing R-plasmid pEB019 were about 10 fold more
than the reversion in the isogenic strains without the plasmid. The possible implications of the superior mutability
potential of Rvplasmid pEB019 compared with pKMI01 in the monitoring and detection of environmental chemical
mutagens using bacterial test system arc highlighted.
