Glutamin-(asparagin-)ase

Glutamin-(asparagin-)ase is an enzyme that catalyzes the hydrolysis of both glutamine and asparagine. These enzymes belong to the broader class of amidases and specifically target the amide bond of these amino acids, releasing ammonia and the corresponding carboxylic acid (glutamic acid from glutamine and aspartic acid from asparagine).

The presence of parentheses in the name signifies that the enzyme possesses dual substrate specificity. It can effectively act on both glutamine and asparagine, although often with differing catalytic efficiencies. The relative activity towards each substrate can vary depending on the specific enzyme source and its characteristics.

These enzymes are found in a variety of organisms, including bacteria, fungi, plants, and animals. They play diverse roles in cellular metabolism, including nitrogen metabolism, amino acid homeostasis, and energy production. In bacteria, they can contribute to the utilization of glutamine and asparagine as nitrogen and carbon sources. In mammalian systems, they are involved in regulating the levels of glutamine and asparagine in various tissues.

Glutamin-(asparagin-)ases have gained attention for their potential therapeutic applications, particularly in cancer treatment. Some cancer cells exhibit a high dependence on glutamine and asparagine for their growth and survival. By depleting these amino acids using glutamin-(asparagin-)ase, cancer cell growth can be inhibited. L-asparaginase, which also exhibits glutaminase activity, is a well-established chemotherapeutic agent used to treat certain types of leukemia and lymphoma. Research is ongoing to develop more selective and potent glutamin-(asparagin-)ase inhibitors as potential anti-cancer drugs.