Induction of the nag regulon of Escherichia coli by N-acetylglucosamine and glucosamine: role of the cyclic AMP-catabolite activator protein complex in expression of the regulon.
The divergent nag regulon located at 15.5 min on the Escherichia coli map encodes genes necessary for growth on N-acetylglucosamine and glucosamine. Full induction of the regulon requires both the presence of N-acetylglucosamine and a functional cyclic AMP (cAMP)-catabolite activator protein (CAP) complex. Glucosamine produces a lower level of induction of the regulon. A nearly symmetric consensus CAP-binding site is located in the intergenic region between nagE (encoding EIINag) and nagB (encoding glucosamine-6-phosphate deaminase). Expression of both nagE and nagB genes is stimulated by cAMP-CAP, but the effect is more pronounced for nagE. In fact, very little expression of nagE is observed in the absence of cAMP-CAP, whereas 50% maximum expression of nagB is observed with N-acetylglucosamine in the absence of cAMP-CAP. Two mRNA 5' ends separated by about 100 nucleotides were located before nagB, and both seem to be similarly subject to N-acetylglucosamine induction and cAMP-CAP stimulation. To induce the regulon, N-acetylglucosamine or glucosamine must enter the cell, but the particular transport mechanism used is not important.
Plumbridge
J A
JA
Institut de Biologie Physico-Chimique, Paris, France.
D000117:Acetylglucosamine / Q000378:metabolism / Q000494:pharmacology*; D019747:Aldose-Ketose Isomerases; D001483:Base Sequence; D001665:Binding Sites; D001692:Biological Transport; D002238:Carbohydrate Epimerases / Q000235:genetics*; D050260:Carbohydrate Metabolism; D003001:Cloning, Molecular; D002373:Cyclic AMP Receptor Protein / Q000378:metabolism*; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development; D015870:Gene Expression; D005809:Genes, Regulator / Q000187:drug effects*; D005838:Genotype; D005944:Glucosamine / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology*; D008969:Molecular Sequence Data; D009154:Mutation; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000302:isolation & purification; D014158:Transcription, Genetic
D002373:Cyclic AMP Receptor Protein; D012333:RNA, Messenger; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; C020582:glucosamine-6-phosphate isomerase; D002238:Carbohydrate Epimerases; D019747:Aldose-Ketose Isomerases; D005944:Glucosamine; D000117:Acetylglucosamine