title: Involvement of ppGpp, ribosome modulation factor, and stationary phase-specific sigma factor sigma(S) in the decrease in cell viability caused by spermidine.
abstract: Accumulation of spermidine in Escherichia coli causes a decrease in cell viability at the late stationary phase of cell growth. The mechanism underlying this effect has been studied. Spermidine accumulation caused an increase in the level of ppGpp and a decrease in ribosome modulation factor (RMF) and stationary phase-specific sigma factor sigma(S), both of which are believed to be involved in cell viability. Transformation of E. coli with the gene for stringent factor, which synthesizes ppGpp, also caused a significant decrease in the levels of RMF and sigma(S) factor and a decrease in cell viability. The results strongly suggest that the accumulation of ppGpp is also involved in the decrease in cell viability and that the sigma(S) factor assists the function of RMF in cell viability.
authors.affiliation: Faculty of Pharmaceutical Sciences, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba, 263-8522, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Apirakaramwong
authors.forename: K
authors.initials: K
authors.lastname: Kashiwagi
authors.forename: V S
authors.initials: VS
authors.lastname: Raj
authors.forename: K
authors.initials: K
authors.lastname: Sakata
authors.forename: Y
authors.initials: Y
authors.lastname: Kakinuma
authors.forename: A
authors.initials: A
authors.lastname: Ishihama
authors.forename: K
authors.initials: K
authors.lastname: Igarashi
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D004926:Escherichia coli / Q000254:growth & development* / Q000378:metabolism*; D029968:Escherichia coli Proteins; D006159:Guanosine Tetraphosphate / Q000378:metabolism*; D012269:Ribosomal Proteins / Q000378:metabolism*; D012808:Sigma Factor / Q000378:metabolism*; D013095:Spermidine / Q000494:pharmacology*
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D012269:Ribosomal Proteins; D012808:Sigma Factor; C063545:ribosome modulation factor, E coli; C069567:sigma factor KatF protein, Bacteria; D006159:Guanosine Tetraphosphate; D013095:Spermidine