title: The isolation and characterization of an alkylating-agent-sensitive yeast mutant, ngs1.
abstract: We have isolated and characterized a mutant of baker's yeast, Saccharomyces cerevisiae, carrying the new mutation, ngs1, which is sensitive to the toxic effects of monofunctional alkylating agents, but normal with respect to 254-nm ultraviolet light sensitivity. ngs1 mutants exhibited more or less normal reversion frequencies for his1-7 and ilv1-92 induced by each of these mutagens. The various sensitivities associated with ngs1 cosegregated and have been shown to be the result of a lesion in a single nuclear gene. Extracts of ngs1 and NGS1+ strains contained approximately equal levels of an activity that removes 3-methyladenine (3MA) and 7-methylguanine (7MG) from DNA in vitro. The mutation also depressed sporulation.
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives / Q000378:metabolism; D000477:Alkylating Agents / Q000494:pharmacology*; D004260:DNA Repair; D005800:Genes, Fungal; D006147:Guanine / Q000031:analogs & derivatives / Q000378:metabolism; D008769:Methylnitronitrosoguanidine; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D013463:Sulfuric Acid Esters
chemical_list: D000477:Alkylating Agents; D013463:Sulfuric Acid Esters; D008769:Methylnitronitrosoguanidine; C025946:3-methyladenine; D006147:Guanine; C008450:7-methylguanine; D000225:Adenine; C007482:dimethyl sulfate