|Superclasses:||Reactions Classified By Conversion Type → Simple Reactions → Chemical Reactions|
|Reactions Classified By Substrate → Small-Molecule Reactions|
EC Number: 18.104.22.168
Note that this reaction equation differs from the official Enzyme Commission reaction equation for this EC number, which can be found here .
The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.
Mass balance status: Balanced.
Direct generic reaction:
a purine ribonucleoside + phosphate ↔ a purine base + α-D-ribose-1-phosphate (22.214.171.124)
Enzyme Commission Primary Name: purine-nucleoside phosphorylase
Enzyme Commission Synonyms: inosine phosphorylase, PNPase, PUNPI, PUNPII, inosine-guanosine phosphorylase, nucleotide phosphatase, purine deoxynucleoside phosphorylase, purine deoxyribonucleoside phosphorylase, purine nucleoside phosphorylase, purine ribonucleoside phosphorylase
Enzyme Commission Summary:
Specificity not completely determined. Can also catalyse ribosyltransferase reactions of the type catalysed by EC 126.96.36.199, nucleoside ribosyltransferase.
Instance reactions of [a purine ribonucleoside + phosphate ↔ a purine base + α-D-ribose-1-phosphate] (188.8.131.52):
i1: adenosine + phosphate ↔ α-D-ribose-1-phosphate + adenine (184.108.40.206)
i2: inosine + phosphate ↔ α-D-ribose-1-phosphate + hypoxanthine (220.127.116.11)
i3: guanosine + phosphate ↔ α-D-ribose-1-phosphate + guanine (18.104.22.168/22.214.171.124)
Saunders69: Saunders PP, Wilson BA, Saunders GF (1969). "Purification and comparative properties of a pyrimidine nucleoside phosphorylase from Bacillus stearothermophilus." J Biol Chem 244(13);3691-7. PMID: 4978445
©2014 SRI International, 333 Ravenswood Avenue, Menlo Park, CA 94025-3493