Glutamine synthetase is a key enzyme involved in the metabolism and biosynthesis of nonessential amino acids in the body. It catalyzes the conversion of glutamate and ammonia to glutamine, which is an important intermediate in the synthesis of other nonessential amino acids. The activity of glutamine synthetase contributes to the production of nonessential amino acids in the body through the following ways:1. Formation of Glutamine: Glutamine synthetase catalyzes the ATP-dependent condensation of glutamate and ammonia to form glutamine. Glutamine is a nonessential amino acid that serves as a nitrogen donor for the synthesis of other nonessential amino acids, nucleotides, and other nitrogen-containing biomolecules.2. Regulation of Nitrogen Metabolism: Glutamine synthetase plays a crucial role in regulating nitrogen metabolism in the body. It helps maintain the balance between the production and utilization of ammonia, preventing toxic levels of ammonia from accumulating in the body. By incorporating ammonia into glutamine, the enzyme helps to detoxify ammonia and make it available for the synthesis of other nonessential amino acids.3. Synthesis of Other Nonessential Amino Acids: Glutamine serves as a precursor for the synthesis of other nonessential amino acids, such as asparagine, alanine, and proline. The conversion of glutamine to these amino acids is catalyzed by specific enzymes, such as asparagine synthetase, alanine aminotransferase, and pyrroline-5-carboxylate synthase, respectively. Thus, the activity of glutamine synthetase indirectly contributes to the production of these nonessential amino acids.4. Glutamate Production: Glutamine can also be converted back to glutamate by the enzyme glutaminase. Glutamate is another nonessential amino acid that serves as a precursor for the synthesis of other amino acids, such as proline and arginine. Additionally, glutamate plays a vital role in the synthesis of the neurotransmitter gamma-aminobutyric acid GABA and the antioxidant molecule glutathione.In summary, the activity of the enzyme glutamine synthetase is essential for the production of nonessential amino acids in the body. It contributes to the formation of glutamine, regulation of nitrogen metabolism, and synthesis of other nonessential amino acids, such as asparagine, alanine, and proline.