PNP
Function
Catalyzes 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 (PubMed:23438750, PubMed:9305964). Preferentially acts on 6-oxopurine nucleosides including inosine and guanosine (PubMed:9305964).
Involvement in disease
Purine nucleoside phosphorylase deficiency
PNPD
A disorder that interrupts both the catabolism of inosine into hypoxanthine and guanosine into guanine, and leads to the accumulation of guanosine, inosine, and their deoxified by-products. The main clinical presentation is recurrent infections due to severe T-cell immunodeficiency. Some patients also have neurologic impairment.
None
The disease is caused by variants affecting the gene represented in this entry.
Pathway
Purine metabolism; purine nucleoside salvage.
Sequence Similarities
Belongs to the PNP/MTAP phosphorylase family.
Tissue Specificity
Expressed in red blood cells; overexpressed in red blood cells (cytoplasm) of patients with hereditary non-spherocytic hemolytic anemia of unknown etiology.
Cellular localization
- Cytoplasm
Alternative names
NP, PNP, Purine nucleoside phosphorylase, Inosine phosphorylase, Inosine-guanosine phosphorylase