glutamine synthetase

enzyme

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June 29, 2026

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Glutamine synthetase is an enzyme that plays a crucial role in cellular metabolism, particularly in animals. It catalyzes a reaction where ammonia is combined with glutamate, using ATP for energy, to form glutamine. This process is vital for detoxifying ammonia, which is toxic to cells.1

Glutamine is an abundant amino acid found in proteins and is widely present in plants. In animals, it's significant because it can cross the blood-brain barrier and is a major component of brain tissue's amino nitrogen. Glutamine is considered a nonessential amino acid, meaning animals can synthesize it themselves. The enzyme glutamine synthetase is subject to various metabolic controls.21

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metabolism
Disposal of nitrogen
…reaction [29] is catalyzed by glutamine synthetase, which is subject to a variety of metabolic controls. The glutamine thus formed gives up the amide nitrogen in the kidney tubules. As a result, glutamate is formed once again, and ammonia is released into the urine.
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…reaction [29] is catalyzed by glutamine synthetase, which is subject to a variety of metabolic controls. The glutamine thus formed gives up the amide nitrogen in the kidney tubules. As a result, glutamate is formed once again, and ammonia is released into the urine.
Read More