Nonprotein Amino Acids

Synonyms

Non-coded amino acids; Non-proteinogenic amino acids

Definition

Amino acids are multifunctional organic compounds that contain at least one amino and one carboxyl group attached to a central carbon atom, whose side chains may vary in length and branching as well as in content of other functional groups or aromatic rings. Amino acids may form numerous molecular structures, where the relative position of the amino and carboxyl function allows their general classification as 2-, 3-, 4-, etc. (also referred to as α, β, γ, etc.) amino acids. Most amino acids have at least one asymmetric carbon and are chiral. Amino acids are classified as nonprotein when they are not part of the 22 such molecules that are translated into proteins by the standard genetic code. They are found in nature, both in biology and extraterrestrial chemistry.

Overview

A large and diverse number of amino acid molecular species not found in proteins have been discovered in the biosphere and in extraterrestrial...