The kinetics of the beta-galactoside-proton symport of Escherichia coli.
beta-Galactoside transport by Escherichia coli occurs with the concomitant uptake of a proton. The kinetics of beta-galactoside uptake at various values of external pH are interpreted in terms of a model in which both the galactoside and the proton are substrates of the transport reaction. The values of some of the kinetic constants for this two-substrate reaction were determined. The observed effects of the protonmotive force on the apparent Michaelis constant for galactoside can be explained in terms of the proton being a substrate of the transport reaction.
D001692:Biological Transport / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects / Q000378:metabolism*; D005697:Galactosides / Q000378:metabolism*; D006027:Glycosides / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D007785:Lactose / Q000494:pharmacology; D008954:Models, Biological; D009598:Nitrophenylgalactosides / Q000378:metabolism; D011522:Protons
D005697:Galactosides; D006027:Glycosides; D011522:Protons; C007816:beta-galactoside; D009598:Nitrophenylgalactosides; D007785:Lactose