Biomaterial Database

Activation of glutaminase by phosphoribosyl-pyrophosphate and its interference with the assay of phosphoribosylpyrophosphate amidotransferase. 1979

R Hahn, and W Oberrauch, and D Mecke

Phosphate-dependent glutaminase (L-glutamine amidohydrolase, EC 3.5.1.2) from rat liver was found to be strongly activated by phosphoribosylpyrophosphate (P-rib-PP), the substrate of amidophosphoribosyltransferase (EC 2.4.2.14). Since the assay of the latter is based on the P-rib-PP-dependent conversion of glutamine to glutamate, the amidotransferase activities determined in crude tissue preparations were found to be too high. The interference of glutaminase, however, could be completely eliminated by its inactivation at 50 degrees C. Amidotransferase was not affected by the heat treatment. Because of the increased rate of the glutamate formation at this temperature, the incubation time of the assay could be significantly reduced.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
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
D010428	Pentosephosphates
D010430	Pentosyltransferases	Enzymes of the transferase class that catalyze the transfer of a pentose group from one compound to another.
D010754	Phosphoribosyl Pyrophosphate	The key substance in the biosynthesis of histidine, tryptophan, and purine and pyrimidine nucleotides.	Pyrophosphate, Phosphoribosyl
D004789	Enzyme Activation	Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.	Activation, Enzyme,Activations, Enzyme,Enzyme Activations
D005972	Glutaminase		Phosphate-Activated Glutaminase,Glutaminase, Phosphate-Activated,Phosphate Activated Glutaminase
D000582	Amidophosphoribosyltransferase	An enzyme, involved in the early steps of purine nucleotide biosynthesis, that catalyzes the formation of 5-phosphoribosylamine from glutamine and phosphoribosylpyrophosphate. EC 2.4.2.14.	Glutamine Phosphoribosyl Pyrophosphate Amidotransferase,Phosphoribosyl Pyrophosphate Amidotransferase,Glutamine-Amidophosphoribosyltransferase,Phosphoribosyldiphosphate 5-Amidotransferase,5-Amidotransferase, Phosphoribosyldiphosphate,Amidotransferase, Phosphoribosyl Pyrophosphate,Glutamine Amidophosphoribosyltransferase,Phosphoribosyldiphosphate 5 Amidotransferase,Pyrophosphate Amidotransferase, Phosphoribosyl
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
D051381	Rats	The common name for the genus Rattus.	Rattus,Rats, Laboratory,Rats, Norway,Rattus norvegicus,Laboratory Rat,Laboratory Rats,Norway Rat,Norway Rats,Rat,Rat, Laboratory,Rat, Norway,norvegicus, Rattus