Amino Acid In chemistry, an amino acid is any molecule that contains both amine and carboxylic acid functional groups.
Alanine, an amino acid is the most widely used in protein construction. It is an important source of energy for the muscles, the brain and the central nervous system. It helps in the metabolism of sugars and organic acids. It also strengthens the immune system by producing antibodies.
In biochemistry, this shorter and more general term is frequently used to refer to alpha amino acids: those amino acids in which the amino and carboxylate functionalities are attached to the same carbon, the so-called a�carbon.
An amino acid residue is what is left of an amino acid once a molecule of water has been lost (an H+ from the nitrogenous side and an OH- from the carboxylic side) in the formation of a peptide .
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