Imine formation is often seen in biochemistry. The example above depicts the formation of a Schiff base between a lysine residue of the enzyme transaminase and the coenzyme PLP. (In the biochemical context we should be in the habit of calling imines Schiff bases.) Transaminase is an important enzyme in the context of metabolic integration as well as nitrogen waste removal. Transaminase catalyzes the interconversion of α-amino amino acids with their corresponding α-keto-acids such as the conversion of glutamate to α-ketoglutarate. In the transaminase mechanism the lysine residue demonstrates an important aspects of its personality, the ability to covalently bind substrates (or in this case a coenzyme) through Schiff base formation.