Characterization of the molecular mechanisms involved in the differential production of erythrose-4-phosphate dehydrogenase, 3-phosphoglycerate kinase and class II fructose-1,6-bisphosphate aldolase in Escherichia coli.
A gapA-pgk gene tandem coding the glyceraldehyde 3-phosphate dehydrogenase and 3-phosphoglycerate kinase, is most frequently found in bacteria. However, in Enterobacteriaceae, gapA is replaced by an epd open reading frame (ORF) coding an erythrose-4-phosphate dehydrogenase and an fbaA ORF coding the class II fructose-1,6-bisphosphate aldolase follows pgk. Although epd expression is very low in Escherichia coli, we show that, in the presence of glucose, the 3 epd, pgk and fbaA ORFs are efficiently cotranscribed from promoter epd P0. Conservation of promoter epd P0 is likely due to its important role in modulation of the metabolic flux during glycolysis and gluconeogenesis. As a consequence, we found that the epd translation initiation region and ORF have been adapted in order to limit epd translation and to create an efficient RNase E entry site. We also show that fbaA is cotranscribed with pgk, from promoter epd P0 or an internal pgk P1 promoter of the extended -10 class. The differential expression of pgk and fbaA also depends upon an RNase E segmentation process, leading to individual mRNAs with different stabilities. The secondary structures of the RNA regions containing the RNase E sites were experimentally determined which brings important information on the structural features of RNase E ectopic sites.
Bardey
Vincent
V
Laboratoire de Maturation des ARN et Enzymologie Moléculaire, UMR 7567 CNRS-UHP Nancy I, Faculté des Sciences et Techniques, BP 239, 54506 Vandoeuvre-lès-Nancy, Cedex, France.
Vallet
Corinne
C
Robas
Nathalie
N
Charpentier
Bruno
B
Thouvenot
Benoit
B
Mougin
Annie
A
Hajnsdorf
Eliane
E
Régnier
Philippe
P
Springer
Mathias
M
Branlant
Christiane
C
D000445:Aldehyde Oxidoreductases / Q000096:biosynthesis / Q000235:genetics*; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D018387:Codon, Initiator / Q000235:genetics; D017124:Conserved Sequence; D004722:Endoribonucleases / Q000737:chemistry; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D029968:Escherichia coli Proteins / Q000096:biosynthesis / Q000235:genetics*; D005634:Fructose-Bisphosphate Aldolase / Q000096:biosynthesis / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D005947:Glucose / Q000494:pharmacology; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010735:Phosphoglycerate Kinase / Q000096:biosynthesis / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D014176:Protein Biosynthesis; D020871:RNA Stability / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D012270:Ribosomes / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects
D018387:Codon, Initiator; D029968:Escherichia coli Proteins; D012333:RNA, Messenger; D000445:Aldehyde Oxidoreductases; C066236:erythrose 4-phosphate dehydrogenase, E coli; D010735:Phosphoglycerate Kinase; D004722:Endoribonucleases; C022537:ribonuclease E; D005634:Fructose-Bisphosphate Aldolase; D005947:Glucose