title: Inhibitory effect of heavy water on mutability of chemically injured Escherichia coli cells.
abstract: After E. coli cells (WP2 and WP2uvrA) were treated with chemical mutagens (methyl methanesulfonate, MMS; N-methyl-N-nitrosourea, MNU; 4-nitroquinoline 1-oxide, 4NQO) in 1/15 M phosphate buffer, the mutability of the treated cells plated on a D2O-agar plate was compared with that plated on an ordinary H2O-agar plate. The mutation frequency decreased more or less on the D2O-agar plate. The D2O-substitution effects, as termed by the relative mutation frequencies (MFD2O/MFH2O), are 0.92 for MMS, 0.29 for MNU, and 0.42 for 4NQO in WP2, and 0.68 for MMS, 0.49 for MNU, and 0.16 for 4NQO in WP2uvrA. The D2O effect seemed to be partly related to the function of the uvrA gene-associated products. The pH dependence of mutability was discussed in connection with the D2O-substitution effect.
authors.affiliation: Faculty of Pharmaceutical Sciences, Nagoya City University, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Hakura
authors.forename: K
authors.initials: K
authors.lastname: Kohda
authors.forename: Y
authors.initials: Y
authors.lastname: Kawazoe
mesh_terms: D015112:4-Nitroquinoline-1-oxide / Q000494:pharmacology*; D003903:Deuterium / Q000494:pharmacology*; D017666:Deuterium Oxide; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics*; D008741:Methyl Methanesulfonate / Q000494:pharmacology*; D008770:Methylnitrosourea / Q000494:pharmacology*; D009152:Mutagenicity Tests; D009153:Mutagens; D009154:Mutation; D009600:Nitroquinolines / Q000494:pharmacology*; D014867:Water / Q000494:pharmacology*
chemical_list: D009153:Mutagens; D009600:Nitroquinolines; D014867:Water; D015112:4-Nitroquinoline-1-oxide; D008770:Methylnitrosourea; D003903:Deuterium; D008741:Methyl Methanesulfonate; D017666:Deuterium Oxide