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The kinetics of the beta-galactoside-proton symport of Escherichia coli.

ABSTRACT: 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.

SUBMITTER: Page MG

PROVIDER: S-EPMC1163091 | biostudies-other | 1981 Jun

REPOSITORIES: biostudies-other

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