Adjective
proteinogenic (comparative more proteinogenic, superlative most proteinogenic)
proteogenic (that serves to produce protein)
Nine proteinogenic amino acids are called "essential" for humans because they cannot be created from other compounds by the human body and so must be taken in as food. Source: Internet
Proline is the only proteinogenic amino acid whose side-group links to the α-amino group and, thus, is also the only proteinogenic amino acid containing a secondary amine at this position. Source: Internet