title: Mutagen stability of alkylation-sensitive mutants of Bacillus subtilis.
abstract: A series of mutations of Bacillus subtilis, conferring sensitivity to methyl methanesulfonate (MMS), were transferred by transformation to a suppressible his(-) stock. The introduction of certain sensitivity mutations prevented the ultraviolet- or MMS-induced, but not the spontaneous, reversion of his(-) to his(+). Not all sensitivity mutations led to this resistance to mutagenesis; a strain with altered deoxyribonucleic acid (DNA) polymerase activity behaved almost normally with respect to its mutagen response, as did an excision-defective, ultraviolet-sensitive strain used as a control. One of the mutagen-stable strains responded to mutagenesis with nitrosomethylguanidine; another appeared stable even to this mutagen. All mutagen-stable strains had DNA polymerase and DNA ligase activity.
mesh_terms: D000473:Alkanes / Q000494:pharmacology; D000477:Alkylating Agents / Q000494:pharmacology*; D000478:Alkylation; D001412:Bacillus subtilis / Q000187:drug effects / Q000201:enzymology / Q000528:radiation effects; D002499:Centrifugation, Density Gradient; D004247:DNA; D004254:DNA Nucleotidyltransferases / Q000032:analysis; D004269:DNA, Bacterial; D003851:Deoxyribonucleases; D005827:Genetics, Microbial; D006639:Histidine; D008025:Ligases / Q000032:analysis; D009153:Mutagens / Q000494:pharmacology*; D009154:Mutation; D009604:Nitrosoguanidines / Q000494:pharmacology; D011830:Radiation Effects; D013451:Sulfonic Acids / Q000494:pharmacology; D014170:Transformation, Genetic; D014316:Tritium; D014466:Ultraviolet Rays
chemical_list: D000473:Alkanes; D000477:Alkylating Agents; D004269:DNA, Bacterial; D009153:Mutagens; D009604:Nitrosoguanidines; D013451:Sulfonic Acids; D014316:Tritium; D006639:Histidine; D004247:DNA; D004254:DNA Nucleotidyltransferases; D003851:Deoxyribonucleases; D008025:Ligases