Isolation and characterization of catabolite repression-resistant mutants of Escherichia coli.
A method has been developed for the isolation of Escherichia coli mutants which are resistant to catabolic repression. The method is based on the fact that a mixture of glucose and gluconate inhibits the development of chemotactic motility in the wild type, but not in the mutants. A motile E. coli strain was mutagenized and grown in glucose and gluconate. Mutants which were able to swim into a tube containing a chemotactic attractant (aspartic acid) were isolated. Most of these mutants were able to produce beta-galactosidase in the presence of glucose and gluconate and were normal in their ability to degrade adenosine 3',5-cyclic monophosphate. Some of these mutants were defective in the glucose phosphotransferase system.
D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000378:metabolism; D002633:Chemotaxis; D002874:Chromosome Mapping; D002876:Chromosomes, Bacterial; D004790:Enzyme Induction / Q000187:drug effects; D004794:Enzyme Repression; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D005696:Galactosidases / Q000096:biosynthesis; D005796:Genes; D005942:Gluconates / Q000378:metabolism; D005947:Glucose / Q000378:metabolism / Q000494:pharmacology; D009154:Mutation; D014368:Tryptophanase / Q000096:biosynthesis
D005942:Gluconates; D015105:3',5'-Cyclic-AMP Phosphodiesterases; D005696:Galactosidases; D014368:Tryptophanase; D005947:Glucose