D-arginase

D-Arginase

Structure of D-Arginase enzyme

D-Arginase is an enzyme that plays a crucial role in the metabolism of the amino acid arginine. It catalyzes the hydrolysis of D-arginine into urea and D-ornithine. This enzyme is found in various organisms, including bacteria, fungi, and mammals.

Structure

The structure of D-Arginase consists of a single polypeptide chain folded into a compact globular shape. It typically contains two metal ions, usually manganese or cobalt, which are essential for its catalytic activity. The active site of D-Arginase is located within a deep pocket formed by several amino acid residues.

Function

D-Arginase is involved in the urea cycle, a metabolic pathway that converts toxic ammonia into urea, which can be safely excreted by the body. In this pathway, D-arginine is hydrolyzed by D-Arginase, producing urea and D-ornithine. D-Ornithine then enters the urea cycle to further participate in the conversion of ammonia to urea.

Role in Health and Disease

D-Arginase plays a crucial role in maintaining nitrogen balance and preventing the accumulation of toxic ammonia in the body. Dysfunction or deficiency of D-Arginase can lead to various health issues. For example, inborn errors of metabolism affecting D-Arginase activity can result in hyperargininemia, a rare genetic disorder characterized by elevated levels of arginine in the blood. This condition can lead to neurological symptoms, developmental delays, and intellectual disabilities.

Applications

D-Arginase has gained attention in recent years due to its potential therapeutic applications. Researchers have explored the use of D-Arginase as a therapeutic agent for various diseases, including cancer. By depleting arginine, which is essential for the growth of certain cancer cells, D-Arginase has shown promise in inhibiting tumor growth. Additionally, D-Arginase has been investigated for its potential role in treating cardiovascular diseases and immune-related disorders.

See Also

• Arginine
• Urea cycle
• Hyperargininemia