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Updated: Oct 10, 2026

Direct Detection of the Acetate-forming Activity of the Enzyme Acetate Kinase
Published on: December 19, 2011
Acceptor substrate inhibits transketolase competitively with respect to donor substrate
O N Solov'eva1, L E Meshalkina, M V Kovina
1Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119899, Russia.
Abstract:
Two substrates of the transketolase reaction are known to bind with the enzyme according to a ping-pong mechanism [1]. It is shown in this work that high concentrations of ribose-5-phosphate (acceptor substrate) compete with xylulose-5-phosphate (donor substrate), suppressing the transketolase activity (Ki = 3.8 mM). However, interacting with the donor-substrate binding site on the protein molecule, the acceptor substrate, unlike the donor substrate, does not cause any change in the active site of the enzyme. The data are interesting in terms of studying the regulatory mechanism of the transketolase activity and the structure of the enzyme-substrate complex.
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