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Updated: Aug 20, 2026

Nucleoside Triphosphates - From Synthesis to Biochemical Characterization
Published on: April 3, 2014
New catalytic mechanism for human purine nucleoside phosphorylase
Fernanda Canduri1, Valmir Fadel, Luiz Augusto Basso
1Programa de Pós-graduação em Biofísica Molecular, Departamento de Física, UNESP, São José do Rio Preto, SP 15054-000, Brazil. canduri@webmail.ibilce.unesp.br
Abstract:
Human purine nucleoside phosphorylase has been submitted to intensive structure-based design of inhibitors, most of them using low-resolution structures of human PNP. Recently, several structures of human PNP have been reported, which allowed redefinition of the active site and understanding of the structural basis for inhibition of PNP by acyclovir and immucillin-H. Based on previously solved human PNP structures, we proposed here a new catalytic mechanism for human PNP, which is supported by crystallographic studies and explains previously determined kinetic data.
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