[PNPH_HUMAN] Defects in PNP are the cause of purine nucleoside phosphorylase deficiency (PNPD) [MIM:613179]. It leads to a severe T-cell immunodeficiency with neurologic disorder in children.
[PNPH_HUMAN] The purine nucleoside phosphorylases catalyze the phosphorolytic breakdown of the N-glycosidic bond in the beta-(deoxy)ribonucleoside molecules, with the formation of the corresponding free purine bases and pentose-1-phosphate.
Purine nucleoside phosphorylase (PNP) catalyzes the phosphorolysis of the N-ribosidic bonds of purine nucleosides and deoxynucleosides. PNP is a target for inhibitor development aiming at T-cell immune response modulation and has been submitted to extensive structure-based drug design. More recently, the 3-D structure of human PNP has been refined to 2.3A resolution, which allowed a redefinition of the residues involved in the substrate-binding sites and provided a more reliable model for structure-based design of inhibitors. This work reports crystallographic study of the complex of Human PNP:guanine (HsPNP:Gua) solved at 2.7A resolution using synchrotron radiation. Analysis of the structural differences among the HsPNP:Gua complex, PNP apoenzyme, and HsPNP:immucillin-H provides explanation for inhibitor binding, refines the purine-binding site, and can be used for future inhibitor design.
Crystal structure of human PNP complexed with guanine.,de Azevedo WF Jr, Canduri F, dos Santos DM, Pereira JH, Bertacine Dias MV, Silva RG, Mendes MA, Basso LA, Palma MS, Santos DS Biochem Biophys Res Commun. 2003 Dec 19;312(3):767-72. PMID:14680831
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
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↑ de Azevedo WF Jr, Canduri F, dos Santos DM, Pereira JH, Bertacine Dias MV, Silva RG, Mendes MA, Basso LA, Palma MS, Santos DS. Crystal structure of human PNP complexed with guanine. Biochem Biophys Res Commun. 2003 Dec 19;312(3):767-72. PMID:14680831 doi:10.1016/j.bbrc.2003.10.190