Growth-phase regulation of the Escherichia coli thioredoxin gene.
The two promoters of Escherichia coli trxA gene were separately cloned into pKO100 as well as pJEL170. Galactokinase expression in cells containing the pKO100 derivatives was found to be negatively correlated with growth rate and was 6- to 20-fold higher in stationary cultures than in exponential cultures. The expression of trxA-galK was induced by amino acid starvation in a RelA(+) strain but not in an isogenic Rel(-) strain indicating that the control involves guanosine 3',5'-bispyrophosphate (ppGpp). RpoS, which appears to be essential for expression of most stationary phase expressed genes, is not required for trxA expression. Increased expression of relA, which increases ppGpp concentration, increases trxA expression.
Lim
C J
CJ
Division of Life Sciences, Kangwon National University, Chuncheon, South Korea. cjlim@cc.kangwon.ac.kr
Daws
T
T
Gerami-Nejad
M
M
Fuchs
J A
JA
D000596:Amino Acids; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D005686:Galactokinase / Q000378:metabolism; D005695:Galactosephosphates / Q000096:biosynthesis; D005786:Gene Expression Regulation; D005798:Genes, Bacterial; D006159:Guanosine Tetraphosphate / Q000378:metabolism; D010957:Plasmids; D011401:Promoter Regions, Genetic; D015719:Single-Strand Specific DNA and RNA Endonucleases; D013879:Thioredoxins / Q000235:genetics*
D000596:Amino Acids; D005695:Galactosephosphates; C029973:galactose-1-phosphate; D006159:Guanosine Tetraphosphate; D013879:Thioredoxins; D005686:Galactokinase; D015719:Single-Strand Specific DNA and RNA Endonucleases