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Updated: Aug 3, 2026

On-chip Isotachophoresis for Separation of Ions and Purification of Nucleic Acids
Published on: March 2, 2012
Transition state analogue discrimination by related purine nucleoside phosphorylases
Erika A Taylor Ringia1, Peter C Tyler, Gary B Evans
1Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
Abstract:
Transition state analogues of PNP, the Immucillins and DADMe-Immucillins, were designed to match transition state features of bovine and human PNPs, respectively. The inhibitors with or without the hydroxyl and hydroxymethyl groups of the substrate demonstrate that inhibitor geometry mimicking that of the transition state confers binding affinity discrimination. This finding is remarkable since crystallographic analysis indicates complete conservation of active site residues and contacts to ligands in human and bovine PNPs.
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