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Updated: Aug 13, 2026

Determination of Protein-ligand Interactions Using Differential Scanning Fluorimetry
Published on: September 13, 2014
Cooperativity and flexibility of active sites in homodimeric transketolase
1A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Russia.
Abstract:
Here we summarize evidence for non-equivalence of two structurally similar active sites in transketolase and other thiamine-dependent enzymes. This non-equivalence takes place when the enzymes interact with various ligands (inhibitors, cations, coenzyme and substrates). Data on different strains in the structure of the holotransketolase subunits are also given. The above results are discussed within the framework of a concept of permanent alternative site oscillation of the transketolase molecule in the presence and in the absence of substrate as a manifestation of a 'flip-flop' mechanism.
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