title: Synthesis, no synthesis, or synthesis and degradation of ribosomal ribonucleic acid in various Escherichia coli strains starved for an amino acid.
abstract: A standard stringent strain of Escherichia coli makes little or no ribosomal ribonucleic acid (RNA) during starvation for an essential amino acid, whereas the isogenic relaxed strain makes both ribosomal and messenger RNA. A third class of strains was found which continues to make ribosomal RNA during starvation, but the RNA made is apparently unstable. There is little accumulation of RNA in the third class of strains, and few complete newly formed chains of (3)H-ribosomal RNA are observed in sedimentation analyses, even after long labeling times.
mesh_terms: D000596:Amino Acids / Q000378:metabolism*; D002250:Carbon Radioisotopes; D002499:Centrifugation, Density Gradient; D003470:Culture Media; D004926:Escherichia coli / Q000254:growth & development / Q000378:metabolism*; D007202:Indicators and Reagents; D008715:Methionine / Q000378:metabolism; D009154:Mutation; D009691:Nucleic Acid Denaturation; D009693:Nucleic Acid Hybridization; D012329:RNA, Bacterial / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000096:biosynthesis; D012335:RNA, Ribosomal / Q000096:biosynthesis*; D014316:Tritium; D014498:Uracil / Q000378:metabolism
chemical_list: D000596:Amino Acids; D002250:Carbon Radioisotopes; D003470:Culture Media; D007202:Indicators and Reagents; D012329:RNA, Bacterial; D012333:RNA, Messenger; D012335:RNA, Ribosomal; D014316:Tritium; D014498:Uracil; D008715:Methionine