title: Effects of chemical and physical mutagens on the frequency of a large genetic duplication in Salmonella typhimurium. I. Induction of duplications.
abstract: In Salmonella typhimurium a simple selection has been described to detect bacteria that are merodiploid for almost one-third of the chromosome. The selective procedure is based upon improved utilization of L-malate as the sole carbon source in merodiploid strains. The spontaneous frequency of the duplication in haploid strains is approximately 10(-4) per cell plated. Following the exposure of a haploid strain to mutagenic agents, there is a dose-dependent increase in the duplication frequency above the spontaneous level. In this paper we describe the induction of genetic duplications in Salmonella typhimurium by X-rays, ultraviolet light (UV), ethyl methanesulfonate (EMS), nitrous acid, and the azaacridine half mustard, ICR-372.
mesh_terms: D000166:Acridines / Q000494:pharmacology; D002876:Chromosomes, Bacterial / Q000187:drug effects / Q000528:radiation effects; D004171:Diploidy; D005020:Ethyl Methanesulfonate / Q000494:pharmacology; D005821:Genetic Techniques; D009153:Mutagens; D009588:Nitrogen Mustard Compounds / Q000494:pharmacology; D009608:Nitrous Acid / Q000494:pharmacology; D012486:Salmonella typhimurium / Q000187:drug effects / Q000235:genetics* / Q000528:radiation effects; D012641:Selection, Genetic; D014466:Ultraviolet Rays; D014965:X-Rays
chemical_list: D000166:Acridines; D009153:Mutagens; D009588:Nitrogen Mustard Compounds; C006092:ICR 372; D005020:Ethyl Methanesulfonate; D009608:Nitrous Acid