Asparagine was first isolated from asparagus juice, where it got its name, becoming the first amino acid to be isolated. Asparagine is a principal and frequently abundant amino acid in nitrogen transport. Asparagine is the beta-amide of aspartic acid, synthesized from aspartic acid and adenosine triphosphate (ATP). The primary function of asparagine is converting one amino acid into another via amination, the process by which an amine group is introduced into an organic molecule, and transamination, the reaction when an amine group is transferred to an alpha-ketoacid. The nervous system requires Asparagine. Asparagine plays an essential role in the synthesis of ammonia.
The measurement of asparagine, along with 23 other amino acids, is included in the Amino Acids in Plasma and the Amino Acids in Urine tests.
More Information
Asparagine (Asn/N) is a non-essential amino acid, meaning that it can be synthesized through specific metabolic pathways in humans and does not need to be obtained from the diet. The precursor of asparagine is oxaloacetate, which is converted to aspartic acid with the help of an enzyme (transaminase). The enzyme transfers the amino group from glutamate to oxaloacetate, producing α-ketoglutarate and aspartic acid. Asparagine synthetase produces asparagine, AMP, glutamate, and pyrophosphate from aspartate, glutamine, and ATP.
Since the asparagine side chain can form powerful hydrogen bonds with the peptide chain, asparagine is often found in large numbers near the beginning and end of α-helices and at the bends in β-sheets (the α-chains and β-sheets refer to the secondary structure of proteins). Glutamine is less helpful because it has an extra methylene group and more conformational entropy.
Asparagine also provides binding sites for N-linked glycosylation, modifying protein chains by adding carbohydrate chains. When heated to high temperatures, asparagine reacts with reducing sugars or reactive carbonyls to produce acrylamide, mainly found in baked goods such as French fries, potato chips, and roasted coffee.
Asparagine, the first amino acid to be isolated, was first isolated in 1806 from abundant asparagus juice—hence its name. The odor observed in some people's urine after eating asparagus is a by-product of the metabolic breakdown of asparagine, asparagine-amino-succinic acid monoamide. Still, it may also be due to other substances.
Asparagine is high in animal products such as dairy, beef, poultry, eggs, fish, and seafood and in plant products such as asparagus, potatoes, legumes, nuts, soy, and whole grains.