Biomaterial Database

Studies of the ammonia-dependent reaction of beef pancreatic asparagine synthetase. 1985

P M Mehlhaff, and C A Luehr, and S M Schuster

We have studied the asparagine synthetase reaction with regard to the ammonia-dependent production of asparagine. Hydroxylamine was shown to be an alternate substrate for the asparagine synthetase reaction, and some of its kinetic properties were examined. The ammonia-dependent reaction was examined with regard to inhibition by asparagine. It was found that asparagine inhibition was partial competitive with respect to ammonia, regardless of the concentration of aspartate. However, when MgATP was not saturating, the inhibition by asparagine became linear competitive. These results were interpreted to be consistent with a kinetic mechanism for asparagine synthetase where ammonia is bound to the enzyme followed by MgATP causing asparagine release.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008025	Ligases	A class of enzymes that catalyze the formation of a bond between two substrate molecules, coupled with the hydrolysis of a pyrophosphate bond in ATP or a similar energy donor. (Dorland, 28th ed) EC 6.	Ligase,Synthetases,Synthetase
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
D010179	Pancreas	A nodular organ in the ABDOMEN that contains a mixture of ENDOCRINE GLANDS and EXOCRINE GLANDS. The small endocrine portion consists of the ISLETS OF LANGERHANS secreting a number of hormones into the blood stream. The large exocrine portion (EXOCRINE PANCREAS) is a compound acinar gland that secretes several digestive enzymes into the pancreatic ductal system that empties into the DUODENUM.
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D006898	Hydroxylamines	Organic compounds that contain the (-NH2OH) radical.
D000641	Ammonia	A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.
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
D001217	Aspartate-Ammonia Ligase	An enzyme that catalyzes the formation of asparagine from ammonia and aspartic acid, in the presence of ATP. EC 6.3.1.1.	Asparagine Synthase,Asparagine Synthetase,Asparagine Synthetase B,Aspartate Ammonia Ligase,Ligase, Aspartate-Ammonia,Synthase, Asparagine,Synthetase B, Asparagine,Synthetase, Asparagine
D019811	Hydroxylamine	A colorless inorganic compound (HONH2) used in organic synthesis and as a reducing agent, due to its ability to donate nitric oxide.	Hydroxylamine Hydrochloride,Hydroxylammonium Chloride