Enhancement of the synthesis of RpoN, Cra, and H-NS by polyamines at the level of translation in Escherichia coli cultured with glucose and glutamate.
Proteins whose synthesis is enhanced by polyamines at the level of translation were identified in a polyamine-requiring mutant cultured in the presence of 0.1% glucose and 0.02% glutamate instead of 0.4% glucose as an energy source. Under these conditions, enhancement of cell growth by polyamines was almost the same as that in the presence of 0.4% glucose. It was found that synthesis of RpoN, Cra, and H-NS was enhanced by polyamines at the level of translation at the early logarithmic phase of growth (A(540) of 0.15). The effects of polyamines on synthesis of RpoN, H-NS, and Cra were due to the existence of unusual Shine-Dalgarno sequences (RpoN and H-NS) and an inefficient GUG initiation codon (Cra) in their mRNAs. Thus, rpoN, cra, and hns genes were identified as new members of the polyamine modulon. Because most of the polyamine modulon genes thus far identified encode transcription factors (RpoS [sigma(38)], Cya, FecI [sigma(18)], Fis, RpoN [sigma(54)], Cra, and H-NS), DNA microarray analysis of mRNA expressed in cells was performed. At the early logarithmic phase of growth, a total of 97 species of mRNAs that were up-regulated by polyamines more than twofold were under the control of seven polyamine modulon genes mentioned above.
Terui
Yusuke
Y
Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chiba 260-8675, Japan.
Higashi
Kyohei
K
Taniguchi
Shiho
S
Shigemasa
Ai
A
Nishimura
Kazuhiro
K
Yamamoto
Kaneyoshi
K
Kashiwagi
Keiko
K
Ishihama
Akira
A
Igarashi
Kazuei
K
D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018387:Codon, Initiator; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D005947:Glucose / Q000378:metabolism / Q000494:pharmacology; D018698:Glutamic Acid / Q000378:metabolism / Q000494:pharmacology; D020411:Oligonucleotide Array Sequence Analysis; D011073:Polyamines / Q000378:metabolism / Q000494:pharmacology*; D014176:Protein Biosynthesis; D051877:RNA Polymerase Sigma 54 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012329:RNA, Bacterial / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D056968:Lac Repressors
D001426:Bacterial Proteins; D018387:Codon, Initiator; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D005947:Glucose; D018698:Glutamic Acid; D011073:Polyamines; D051877:RNA Polymerase Sigma 54; D012329:RNA, Bacterial; D012333:RNA, Messenger; D012097:Repressor Proteins; C031908:H-NS protein, bacteria; C497751:rpoN protein, E coli; C068837:FruR protein, Bacteria; D056968:Lac Repressors