Today's Hours: 8:00am - 10:00pm
Lane Medical Library

Search

Filter Results

Did You Mean:

Search Results

Sort by
relevance
  • Journal
    Digital Access
    Provider
    Version
    Wiley
    v. 1-, 2021-
    PubMed Central
    v. 1-, 2021-
  • Article
    Rephaeli AW, Saier MH.
    J Biol Chem. 1978 Nov 10;253(21):7595-7.
    The sugar phosphate:sugar transphosphorylation reaction catalyzed by the glucose Enzyme II complex of the phosphotransferase system has been analyzed kinetically. Initial rates of phosphoryl transfer from glucose-6-P to methyl alpha-glucopyranoside were determined with butanol/urea-extracted membranes from Salmonella typhimurium strains. The kinetic mechanism was shown to be Bi-Bi Sequential, indicating that the Enzyme II possesses nonoverlapping binding sites for sugar and sugar phosphate. Binding of the two substrates appears to occur in a positively cooperative fashion. A mutant with a defective glucose Enzyme II was isolated which transported methyl alpha-glucoside and glucose with reduced maximal velocities and higher Km values. In vitro kinetic studies of the transphosphorylation reaction catalyzed by the mutant enzyme showed a decrease in maximal velocity and increases in the Km values for both the sugar and sugar phosphate substrates. These results are consistent with the conclusion that a single Enzyme II complex catalyzes both transport and transphosphorylation of its sugar substrates.
    Digital Access Access Options