title: Metabolic control of Klebsiella pneumoniae mRNA degradation by the availability of fixed nitrogen.
abstract: The chemical and functional stability of Klebsiella pneumoniae mRNAs was dependent on the nitrogen status of the organism. During exponential growth on N2 or NH+4 as N-source the half-lives of mRNAs were 10 and 4 min, respectively. When NH+4-grown cells were starved of NH+4 for 3 h, under which conditions the nitrogen fixation (nif) genes were derepressed, the half-life of mRNAs increased to 20 min. Addition of NH+4 to such N-starved suspensions rapidly destabilized mRNAs with a resultant half-life of 9 min. This destabilization occurred even in the presence of transcription inhibitors, which indicated metabolic control of mRNA degradation. Under most conditions studied the functional decay of nif-specific mRNAs paralleled the decay of bulk mRNAs.
mesh_terms: D000645:Ammonium Sulfate / Q000378:metabolism; D005798:Genes, Bacterial; D006207:Half-Life; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism; D009586:Nitrogen Fixation; D011370:Proflavine / Q000494:pharmacology; D012329:RNA, Bacterial / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D012293:Rifampin / Q000494:pharmacology
chemical_list: D012329:RNA, Bacterial; D012333:RNA, Messenger; D011370:Proflavine; D009584:Nitrogen; D000645:Ammonium Sulfate; D012293:Rifampin