Catabolite repression in Escherichia coli mutants lacking cyclic AMP receptor protein.
Pleiotropic carbohydrate-positive pseudorevertants have been isolated from a specific class of rho-crp double mutants of Escherichia coli carrying both defective transcription termination protein, rho, and cyclic AMP receptor protein. The modulation of catabolite repression of beta-galactosidase, amylomaltase, and tryptophanase has been studied in the pseudorevertants. It has been found that these mutants exhibit catabolite repression. Because catabolite-sensitive operons can be expressed in the absence of functional cyclic AMP receptor protein, this would suggest on the one hand that the cyclic AMP-receptor protein complex is not the exclusive mediator of catabolite repression and on the other hand that rho might be involved in the regulation of catabolite-sensitive operons.
D000242:Cyclic AMP / Q000378:metabolism; D004794:Enzyme Repression; D004926:Escherichia coli / Q000235:genetics*; D005964:Glucosyltransferases / Q000235:genetics; D006004:Glycogen Debranching Enzyme System; D009154:Mutation; D011953:Receptors, Cyclic AMP / Q000235:genetics*; D012234:Rho Factor / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*; D014368:Tryptophanase / Q000235:genetics; D001616:beta-Galactosidase / Q000235:genetics
D006004:Glycogen Debranching Enzyme System; D011953:Receptors, Cyclic AMP; D012234:Rho Factor; D014157:Transcription Factors; D000242:Cyclic AMP; D005964:Glucosyltransferases; C020569:4 alpha-glucanotransferase; D001616:beta-Galactosidase; D014368:Tryptophanase