Asparaginine is a non-essential amino acid that was first isolated from sprouting soybeans. Structurally similar to aspartic acid, with an additional amino group on the main carbon skeleton, Asparaginine aids in the metabolic functioning of brain and nervous system cells. When the extra amino group is removed by the brain, the resulting aspartic acid acts as an excitatory transmitter. Aspartic acid has been used to help with fatigue and depression, and may be a mild immune stimulant as well. In the body, removal of asparaginines extra amino group allows it to be used interchangeably with aspartic acid in basic protein building. It is easily supplied in normal diets and no toxic effects are known.