Catabolite control of Escherichia coli regulatory protein BglG activity by antagonistically acting phosphorylations.
In bacteria various sugars are taken up and concomitantly phosphorylated by sugar-specific enzymes II (EII) of the phosphoenolpyruvate:sugar phosphotransferase system (PTS). The phosphoryl groups are donated by the phosphocarrier protein HPr. BglG, the positively acting regulatory protein of the Escherichia coli bgl (beta-glucoside utilization) operon, is known to be negatively regulated by reversible phosphorylation catalyzed by the membrane spanning beta-glucoside-specific EIIBgl. Here we present evidence that in addition BglG must be phosphorylated by HPr at a distinct site to gain activity. Our data suggest that this second, shortcut route of phosphorylation is used to monitor the state of the various PTS sugar availabilities in order to hierarchically tune expression of the bgl operon in a physiologically meaningful way. Thus, the PTS may represent a highly integrated signal transduction network in carbon catabolite control.
Görke
B
B
Institut für Biologie III, Universität, Schänzlestrasse 1, D-79104 Freiburg, Germany.
Rak
B
B
D001426:Bacterial Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001592:Benzyl Alcohols / Q000378:metabolism; D001692:Biological Transport; D050260:Carbohydrate Metabolism; D002244:Carbon / Q000378:metabolism; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D015536:Down-Regulation; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D005816:Genetic Complementation Test; D005960:Glucosides; D047908:Intracellular Signaling Peptides and Proteins; D007544:Isopropyl Thiogalactoside; D008954:Models, Biological; D009154:Mutation; D009876:Operon / Q000235:genetics; D010710:Phosphates / Q000378:metabolism; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation; D011494:Protein Kinases; D016601:RNA-Binding Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D013728:Terminator Regions, Genetic / Q000235:genetics
D001426:Bacterial Proteins; D001592:Benzyl Alcohols; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; D005960:Glucosides; D047908:Intracellular Signaling Peptides and Proteins; D010710:Phosphates; D016601:RNA-Binding Proteins; C064872:antiterminator proteins, Bacteria; C028640:fructose-induced HPr-like protein, bacteria; D007544:Isopropyl Thiogalactoside; C005696:salicin; D002244:Carbon; D011494:Protein Kinases; C488924:fruB protein, E coli; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; C030182:phosphocarrier protein HPr