title: The role of energy-generating processes in the degradation of guanosine tetrophosphate, ppGpp, in Escherichia coli.
abstract: The effect of energy limitation on the intracellular level of guanosine 5'-diphosphate, 3'-diphosphate (ppGpp) was investigated. Glucose exhaustion, as well as uncoupling of oxidative phosphorylation, evokes an immediate increase in the ppGpp concentration. This increase is a consequence of a lowered degradation rate of the nucleotide. The level of ppGpp, which determines the rate of ribosomal RNA synthesis, is thus subject to a double control system: amino acyl-tRNA availability governs the rate of synthesis while energy metabolism governs the rate of degradation.
mesh_terms: D004140:Dinitrophenols / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism / Q000494:pharmacology; D006150:Guanine Nucleotides / Q000378:metabolism*; D007700:Kinetics; D010085:Oxidative Phosphorylation; D013045:Species Specificity
chemical_list: D004140:Dinitrophenols; D006150:Guanine Nucleotides; D005947:Glucose