Autophosphorylation of enzyme I of the Escherichia coli phosphoenolpyruvate:sugar phosphotransferase system requires dimerization.
Enzyme I of the Escherichia coli phosphoenolpyruvate:sugar phosphotransferase system undergoes a slow monomer-dimer transition. In vitro autophosphorylation of Enzyme I by PEP was studied at limiting concentrations of the protein. Addition to incubation mixtures containing wild-type Enzyme I of inactive or low-activity mutant forms of Enzyme I resulted in stimulation of autophosphorylation activity. The kinetics of the activation fit well to a model in which the active form of Enzyme I is the dimer. These experiments provide support for the argument that only the dimeric form of Enzyme I can be autophosphorylated.
Seok
Y J
YJ
Department of Microbiology, College of Natural Sciences, Seoul National University, Korea.
Zhu
P P
PP
Koo
B M
BM
Peterkofsky
A
A
D019281:Dimerization; D004926:Escherichia coli / Q000201:enzymology*; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000737:chemistry* / Q000378:metabolism*; D010766:Phosphorylation
D010731:Phosphoenolpyruvate Sugar Phosphotransferase System