Biomaterial Database

[Purine metabolites in the activity of purine nucleoside phosphorylase (author's transl)]. 1976

R Fusté, and J Bozal

In the phosphorolytic degradation catalyzed by chicken liver PNPase (E.C. 2.4.2.1) inosine appears to behave as a better substrate than xanthosine. Hypoxanthine, xanthine, guanine and purine (1 X 10(-1)M) appear to be inhibitors of the pigeon liver PNPase, whereas allopurinol, ATP, ITP, CTP and UTP (1. X 10(-3) M) do not inhibit the enzyme. Both PNPase activities exhibit the same optimum temperature (37-40 degrees C). Chicken liver PNPase optimum pH is in the range 6.5-7, whereas that of pigeon liver is in the range 7-7.5. Lineweaver-Burk plots for the inosine phosphorolysis catalyzed by chicken liver PNPase yielded straight lines if substrate concentrations were lower than 1 X 10(-4) M but concave downward curves at higher concentrations. This activation increases when the homogenates are stored at 4 degrees C and pH = 7 during 24 h or more; pigeon liver PNPase does not show this activation phenomenon.

UI	MeSH Term	Description	Entries
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D010430	Pentosyltransferases	Enzymes of the transferase class that catalyze the transfer of a pentose group from one compound to another.
D010856	Columbidae	Family in the order COLUMBIFORMES, comprised of pigeons or doves. They are BIRDS with short legs, stout bodies, small heads, and slender bills. Some sources call the smaller species doves and the larger pigeons, but the names are interchangeable.	Columba livia,Doves,Pigeons,Domestic Pigeons,Feral Pigeons,Rock Doves,Rock Pigeons,Domestic Pigeon,Dove,Dove, Rock,Doves, Rock,Feral Pigeon,Pigeon,Pigeon, Domestic,Pigeon, Feral,Pigeon, Rock,Pigeons, Domestic,Pigeons, Feral,Pigeons, Rock,Rock Dove,Rock Pigeon
D011683	Purine-Nucleoside Phosphorylase	An enzyme that catalyzes the reaction between a purine nucleoside and orthophosphate to form a free purine plus ribose-5-phosphate. EC 2.4.2.1.	Inosine Phosphorylase,Nicotinamide Riboside Phosphorylase,Purine Nucleoside Phosphorylases,Nucleoside Phosphorylases, Purine,Phosphorylase, Inosine,Phosphorylase, Nicotinamide Riboside,Phosphorylase, Purine-Nucleoside,Phosphorylases, Purine Nucleoside,Purine Nucleoside Phosphorylase,Riboside Phosphorylase, Nicotinamide
D011684	Purine Nucleosides	Purines with a RIBOSE attached that can be phosphorylated to PURINE NUCLEOTIDES.	Purine Nucleoside,Nucleoside, Purine,Nucleosides, Purine
D002645	Chickens	Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.	Gallus gallus,Gallus domesticus,Gallus gallus domesticus,Chicken
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia