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Updated: Aug 19, 2026

Direct Detection of the Acetate-forming Activity of the Enzyme Acetate Kinase
Published on: December 19, 2011
An investigation of the carboxyl group function in the active center of transketolase
Abstract:
Transketolase from baker's yeast is rapidly inactivated in the presence of 1-ethyl-3 (3'-dimethylaminopropyl)-carbodiimide. pKa of the modified carboxyl groups is approximately 6.5. An investigation of the initial steps of enzymatic catalysis monitored by a changes in the circular dichroism spectra and in an oxidation reaction with ferricyanide made it possible to conclude that the modification interferes with the donor substrate attachment to the enzyme. Evidence obtained was suggesting that the carboxyl group of the active center facilitates dissociation of a proton from the carbon atom in the second position of the thiamine pyrophosphate thiazolium ring.
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