title: Liquid holding increases mutation induction by formaldehyde and some other cross-linking agents in Escherichia coli K12.
abstract: The induction by some cross-linking agents of forward mutations leading to nalidixic acid resistance in Escherichia coli K12/343/113 was considerably enhanced when a 24-h period of liquid holding was interpolated between treatment and growth phase. Liquid holding increased the mutagenic effectiveness of nor-nitrogen mustard (NNM) 28-fold, of phosphoramide mustard (PAM) 10-fold, and of tris-ethyleneimino)-phosphineoxide (TEPA), tris(chloroethyl)amine (TCEA) and chloroacetaldehyde (CAA) 3-fold, over the complete concentration range. By contrast, the activities of cisplatin (CDDP), transplatin (TDDP) and chloracetamide-N-metholol (CAM) were slightly decreased after liquid holding. Liquid holding did not measurably influence the mutagenicity of formaldehyde at low concentrations, whereas at higher concentrations an 8-fold increase was observed. As opposed to the considerable activity in the Uvr+ strain, formaldehyde was found not to be mutagenically active in an E. coli strain carrying a deletion of the uvrB gene.
authors.affiliation: Department of Radiation Genetics and Chemical Mutagenesis, University of Leiden, Syluius Laboratories, The Netherlands.
authors.forename: J A
authors.initials: JA
authors.lastname: Zijlstra
mesh_terms: D003432:Cross-Linking Reagents / Q000008:administration & dosage*; D004249:DNA Damage; D004351:Drug Resistance; D004926:Escherichia coli / Q000187:drug effects; D005557:Formaldehyde / Q000008:administration & dosage*; D009152:Mutagenicity Tests; D009154:Mutation / Q000187:drug effects*; D009268:Nalidixic Acid / Q000494:pharmacology; D013997:Time Factors
chemical_list: D003432:Cross-Linking Reagents; D005557:Formaldehyde; D009268:Nalidixic Acid