Evidence against the physiological role of acetyl phosphate in the phosphorylation of the ArcA response regulator in Escherichia coli.
The Arc two-component signal transduction system of Escherichia coli comprises the ArcB sensor kinase and the ArcA response regulator. Under anoxic growth conditions, ArcB autophosphorylates and transphos-phorylates ArcA, which, in turn, represses or activates its target operons. ArcA has been shown to be able to autophosphorylate in vitro at the expense of acetyl-P. Here, the in vivo effect of acetyl phosphate on the redox signal transduction by the Arc system was assessed. Our results indicate that acetyl phosphate can modulate the expression of ArcA-P target genes only in the absence of ArcB. Therefore, the acetyl phosphate dependent ArcA phosphorylation route does not seem to play a significant role under physiological conditions.
Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115, USA.
Xueqiao
X
Liu
Gabriela R
GR
Peña Sandoval
Barry L
BL
Wanner
Won Seok
WS
Jung
Dimitris
D
Georgellis
Ohsuk
O
Kwon
D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism*; D004926:Escherichia coli / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000378:metabolism*; D008954:Models, Biological; D010755:Organophosphates / Q000378:metabolism*; D010766:Phosphorylation; D012097:Repressor Proteins / Q000378:metabolism*
D001425:Bacterial Outer Membrane Proteins; D029968:Escherichia coli Proteins; D010755:Organophosphates; D012097:Repressor Proteins; C041610:arcA protein, E coli; C011632:acetyl phosphate