Search results
Results from the WOW.Com Content Network
2-(N ω-L-arginino)succinate = fumarate + L-arginine. Located in liver cytosol, it is the fourth enzyme of the urea cycle and involved in the biosynthesis of arginine in all species and the production of urea in ureotelic species. [2] Mutations resulting in low activity of the enzyme increase levels of urea in the body and result in various ...
The enzyme endothelial nitric oxide synthase produces nitric oxide from arginine in endothelial cells. [9] Argininosuccinate synthetase and argininosuccinate lyase recycle citrulline, a byproduct of nitric oxide production, into arginine. Since nitric oxide is an important signaling molecule, this role of ASS is important to vascular physiology.
Arginine is synthesized from citrulline in the urea cycle by the sequential action of the cytosolic enzymes argininosuccinate synthetase and argininosuccinate lyase. This is an energetically costly process, because for each molecule of argininosuccinate that is synthesized, one molecule of adenosine triphosphate (ATP) is hydrolyzed to adenosine ...
Nitric oxide synthases (EC 1.14.13.39) (NOSs) are a family of enzymes catalyzing the production of nitric oxide (NO) from L-arginine. NO is an important cellular signaling molecule. It helps modulate vascular tone, insulin secretion, airway tone, and peristalsis, and is involved in angiogenesis and neural development.
Arginine is considered a non-essential amino acid since normal cells can synthesize it from citrulline and aspartate using the enzymes argininosuccinate synthase 1 (ASS1) and argininosuccinate lyase (ASL). Consequently, depleting arginine can be an effective therapeutic approach.
L-Arginine:glycine amidinotransferase (AGAT; EC 2.1.4.1) is the enzyme that catalyses the transfer of an amidino group from L-arginine to glycine. The products are L-ornithine and glycocyamine, also known as guanidinoacetate, the immediate precursor of creatine. Creatine and its phosphorylated form play a central role in the energy metabolism ...
Arginase (EC 3.5.3.1, arginine amidinase, canavanase, L-arginase, arginine transamidinase) is a manganese-containing enzyme. The reaction catalyzed by this enzyme is: arginine + H 2 O → ornithine + urea. It is the final enzyme of the urea cycle. It is ubiquitous to all domains of life.
Some cells synthesize argininosuccinic acid from citrulline and aspartic acid and use it as a precursor for arginine in the urea cycle (or citrulline-NO cycle), releasing fumarate as a by-product to enter the TCA cycle. The enzyme that catalyzes the reaction is argininosuccinate synthetase. [3] [4]