Open AccessInteraction of enzyme I of the phosphoenolpyruvate:sugar phosphotransferase system with adenylate cyclase of Escherichia coli.
Author(s) -
Alan Peterkofsky,
Celia Gazdar
Publication year - 1975
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.72.8.2920
Subject(s) - adenylate kinase , cyclase , pep group translocation , phosphoenolpyruvate carboxykinase , biochemistry , phosphotransferase , dephosphorylation , enzyme , chemistry , phosphorylation , biology , phosphatase
Transient repression by glucose of induced enzyme synthesis involves lowering of intracellular cAMP levels. This glucose effect is partially explained by a glucose inhibition of adenylate cyclase [EC 4.6.1.1; ATP pyrophosphate-lyase(cyclizing)]. Since the phosphoenolpyruvate:sugar phosphotransferase system has been implicated in repression phenomena, an investigation was made of adenylate cyclase activity in mutants of that transport system. The results suggest that glucose phosphorylation is not necessary for inhibition of adenylate cyclase since an HPr mutant retained sensitivity to glucose inhibition. The results also suggest that adenylate cyclase activity requires the presence of Enzyme I in a phosphorylated form and that adenylate cyclase activity may be regulated by a phosphorylation-dephosphorylation mechanism.