PUNP, or Purine nucleoside phosphorylase, is a human gene encoded by PNP. It may also be known as: PNP; Inosine phosphorylase; Inosine-guanosine phosphorylase; NP; PRO1837. The encoded protein is an enzyme with an amino acid length of 289 and a mass of 32.1 kDa. Other isoforms may exist. PUNP is a member of the PNP/MTAP phosphorylase family. Homologs of this gene exist in other organisms, including: Rat, Frog, Nematode, Chicken.