Final answer:
Bioactive molecules derived from arginine include nitric oxide, urea, ornithine, polyamines, and creatine. Arginine metabolism is crucial for physiological functions and cell growth.
Step-by-step explanation:
Several bioactive molecules are derived from the amino acid arginine. One of the primary products is nitric oxide (NO), a crucial compound in various physiological processes including vasodilation, neurotransmission, and immune response. As part of the urea cycle, arginine is hydrolyzed by the enzyme arginase to form ornithine and urea, with ornithine being a key molecule in the cycle that ultimately assists in the excretion of ammonia. Additionally, arginine can lead to the formation of polyamines, such as putrescine, spermidine, and spermine, which are vital for cell growth and differentiation. Arginine also plays a role in the biosynthesis of creatine, a molecule important for energy storage in muscle and brain cells.
In a pathological context, arginine metabolism disorders, such as hyperargininemia and argininosuccinic aciduria, underline the importance of arginine in human biochemistry. For instance, patients with argininosuccinic aciduria lack the enzyme argininosuccinase which leads to an accumulation of argininosuccinic acid in plasma and cerebrospinal fluid.
Finally, arginine-rich peptides have been researched as potential carriers for intracellular protein delivery due to their ability to permeate cell membranes.