title: Regulatory state of ribosomal genes and physiological changes in the concentration of free ribonucleic acid polymerase in Escherichia coli.
abstract: The concept of promoter efficiency is introduced as frequency of RNA chain initiation at a given promoter normalized to the intracellular concentration of free (but functional) RNA polymerase. Previous observations from this laboratory on the synthesis of ribosomes and beta-galactosidase are used to show that during a nutritional shift-up from succinate minimal to glucose-amino acids medium (3-fold increase in steady-state growth rate) the concentration of free (active) RNA polymerase decreases to one-quarter of the pre-shift value and the promoter efficiencies of the genes for ribosomal RNA and ribosomal proteins increase 9- and 6-fold respectively. This extent of control of ribosomal genes is much greater than expected on the basis of the increase in the rate of ribosome synthesis (3-fold).
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology* / Q000648:ultrastructure; D005696:Galactosidases / Q000096:biosynthesis; D005809:Genes, Regulator; D005947:Glucose / Q000378:metabolism; D007700:Kinetics; D009876:Operon; D012329:RNA, Bacterial / Q000378:metabolism; D012335:RNA, Ribosomal / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*; D013386:Succinates / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D000596:Amino Acids; D012329:RNA, Bacterial; D012335:RNA, Ribosomal; D013386:Succinates; D012321:DNA-Directed RNA Polymerases; D005696:Galactosidases; D005947:Glucose