title: Specific mutator mutation in Escherichia coli B strain WP2 . trp- lac-.
mesh_terms: D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000235:genetics* / Q000528:radiation effects; D009154:Mutation; D013307:Streptomycin; D014364:Tryptophan / Q000235:genetics; D014466:Ultraviolet Rays
chemical_list: D014364:Tryptophan; D013307:Streptomycin