title: Mitomycin C-induced expression of trpA of Salmonella typhimurium inserted into the plasmid ColE1.
abstract: EcoRI endonuclease digestion of the deoxyribonucleic acid of a phi80 transducing phage carrying the entire tryptophan (trp) operon of Salmonella typhimurium (phi80 S.t.trpE-A) yielded a 4.3 X 10(6)-dalton fragment containing intact trpE, trpD, and trpC and a 3.35 X 10(6)-dalton fragment containing intact trpA. The trpA fragment inserted into EcoRI-cleaved plasmids ColE1 and CR1 was expressed regardless of its orientation of insertion. Mitomycin C, a compound that induces colicin E1 production in ColE1-containing bacteria, stimulated tryptophan synthetase alpha production in cells containing ColE1-TRPA plasmids with the trpA fragment inserted in one orientation but not the other. We conclude that in the inducible plasmids trpA can be expressed from the colicin E1 promoter.
mesh_terms: D003087:Colicins / Q000096:biosynthesis*; D005111:Extrachromosomal Inheritance; D008937:Mitomycins / Q000494:pharmacology*; D009876:Operon / Q000187:drug effects; D010957:Plasmids; D012486:Salmonella typhimurium / Q000378:metabolism*; D014367:Tryptophan Synthase / Q000096:biosynthesis*
chemical_list: D003087:Colicins; D008937:Mitomycins; D014367:Tryptophan Synthase