title: Isolation and characterization of thymidylate synthetase mutants of Xanthomonas maltophilia.
abstract: Thymidylate synthetase mutants of Xanthomonas maltophilia ATCC 13270 were isolated on a solid minimal medium containing 50 mg/l thymidine and a high concentration of trimethoprim (500 mg/l). It was found that a high concentration of trimethoprim was required to prevent background growth of the wild-type strain. The isolated mutants could grow on thymidine or dTMP at a concentration of 50 mg/l while they were unable to grow on 1000 mg/l thymine or 50 mg/l deoxyuridine. Thymidylate synthetase activity was assayed in the wild-type cells and in the mutant cells but only the wild-type cells contained measurable enzyme activity.
authors.affiliation: Department of Biological Sciences, University of Southern Mississippi, Hattiesburg 39406.
authors.forename: T P
authors.initials: TP
authors.lastname: West
mesh_terms: D003470:Culture Media; D009154:Mutation; D013936:Thymidine / Q000378:metabolism; D013940:Thymidylate Synthase / Q000378:metabolism*; D014295:Trimethoprim / Q000494:pharmacology; D014974:Xanthomonas / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification
chemical_list: D003470:Culture Media; D014295:Trimethoprim; D013940:Thymidylate Synthase; D013936:Thymidine