Catabolite control of Escherichia coli regulatory protein BglG activity by antagonistically acting phosphorylations

• Published in: The EMBO journal Vol. 18; no. 12; pp. 3370 - 3379
• Main Authors: Görke, Boris, Rak, Bodo
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 15-06-1999
• Subjects: Bacterial Proteins - antagonists & inhibitors; Bacterial Proteins - chemistry; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Benzyl Alcohols - metabolism; Biological Transport; Carbohydrate Metabolism; Carbon - metabolism; carbon catabolite control; Carrier Proteins - genetics; Carrier Proteins - metabolism; Down-Regulation; Escherichia coli; Escherichia coli - enzymology; Escherichia coli - genetics; Escherichia coli - growth & development; Escherichia coli - metabolism; Escherichia coli Proteins; Gene Expression Regulation, Bacterial; gene regulation; Genetic Complementation Test; Glucosides; Isopropyl Thiogalactoside; Models, Biological; Mutation; Operon - genetics; Phosphates - metabolism; Phosphoenolpyruvate Sugar Phosphotransferase System - genetics; Phosphoenolpyruvate Sugar Phosphotransferase System - metabolism; phosphoenolpyruvate:sugar phosphotransferase system; Phosphorylation; protein phosphorylation; RNA-Binding Proteins - antagonists & inhibitors; RNA-Binding Proteins - chemistry; RNA-Binding Proteins - genetics; RNA-Binding Proteins - metabolism; Signal Transduction; Terminator Regions, Genetic - genetics
• ISSN: 0261-4189; 1460-2075; 1460-2075
• DOI: 10.1093/emboj/18.12.3370

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 (β‐glucoside utilization) operon, is known to be negatively regulated by reversible phosphorylation catalyzed by the membrane spanning β‐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.