A novel fermentation/respiration switch protein regulated by enzyme IIAGlc in Escherichia coli.
The bacterial phosphoenolpyruvate:sugar phosphotransferase system regulates a variety of physiological processes as well as effecting sugar transport. The crr gene product (enzyme IIA(Glc) (IIA(Glc))) mediates some of these regulatory phenomena. In this report, we characterize a novel IIA(Glc)-binding protein from Escherichia coli extracts, discovered using ligand-fishing with surface plasmon resonance spectroscopy. This protein, which we named FrsA (fermentation/respiration switch protein), is the 47-kDa product of the yafA gene, previously denoted as "function unknown." FrsA forms a 1:1 complex specifically with the unphosphorylated form of IIA(Glc), with the highest affinity of any protein thus far shown to interact with IIA(Glc). Orthologs of FrsA have been found to exist only in facultative anaerobes belonging to the gamma-proteobacterial group. Disruption of frsA increased cellular respiration on several sugars including glucose, while increased FrsA expression resulted in an increased fermentation rate on these sugars with the concomitant accumulation of mixed-acid fermentation products. These results suggest that IIA(Glc) regulates the flux between respiration and fermentation pathways by sensing the available sugar species via a phosphorylation state-dependent interaction with FrsA.
Koo
Byoung-Mo
BM
Laboratory of Macromolecular Interactions, School of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul 151-742, Korea.
Yoon
Mi-Jeong
MJ
Lee
Chang-Ro
CR
Nam
Tae-Wook
TW
Choe
Young-Jun
YJ
Jaffe
Howard
H
Peterkofsky
Alan
A
Seok
Yeong-Jae
YJ
D000595:Amino Acid Sequence; D002352:Carrier Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D005285:Fermentation; D005798:Genes, Bacterial; D007700:Kinetics; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010101:Oxygen Consumption; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000378:metabolism*
D002352:Carrier Proteins; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; C032242:crr protein, E coli; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System