title: The role of methionine transport-defective mutations in resistance to methionine sulphoximine in Salmonella typhimurium.
abstract: Two classes of Salmonella typhimurium mutants resistant to inhibitory methionine analogues and defective in methionine transport have been examined. A mutant of the first class, resistant to alpha-methylmethionine, was shown by conjugation analysis to possess a single mutation in the metP gene which specifies a methionine transport system. Mutants of the second class, resistant to alpha-methylmethionine and methionine sulphoximine, possess two mutations. One is in the metP gene, which accounts for resistance to alpha-methylmethionine, and the other is in a gene designated glnP which results in reduced L-glutamine transport. Both of these mutations are required for resistance to methionine sulphoximine. A transduction analysis of three metP mutations was performed, based on the fact that they prevent growth of methionine-requiring strains on D-methionine. Two of the mutants are closely linked and therefore probably in the same gene, whereas the third mutant might be in a different gene.
mesh_terms: D001692:Biological Transport; D002874:Chromosome Mapping; D002876:Chromosomes, Bacterial; D003227:Conjugation, Genetic; D004352:Drug Resistance, Microbial; D005973:Glutamine / Q000378:metabolism; D008715:Methionine / Q000031:analogs & derivatives / Q000378:metabolism*; D008717:Methionine Sulfoximine / Q000494:pharmacology*; D009154:Mutation; D012486:Salmonella typhimurium / Q000187:drug effects / Q000378:metabolism*
chemical_list: D005973:Glutamine; D008717:Methionine Sulfoximine; D008715:Methionine