title: A recombination-dependent replicating instability in Salmonella typhimurium.
abstract: The aromatic amino acid-requiring mutant of Salmonella typhimurium aroD321 has a stable requirement for phenylalanine and tyrosine but is highly unstable in its requirement for tryptophan. Tryptophan requiring cells derived from this strain are themselves unstable and revert back to a requirement for only phenylalanine and tyrosine. This instability is cotransducible with the aroD region and is totally dependent on the presence of a rec+ gene in the cell. These observations are interpreted in terms of a gene duplicating and excising mechanism which is itself dependent upon the normal (rec+) recombinational ability of the cell.
mesh_terms: D004261:DNA Replication; D009154:Mutation; D010649:Phenylalanine / Q000378:metabolism; D011995:Recombination, Genetic; D012486:Salmonella typhimurium / Q000378:metabolism*; D014364:Tryptophan / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism
chemical_list: D014443:Tyrosine; D010649:Phenylalanine; D014364:Tryptophan