Padanamide A (actinoramide A) was isolated independently from marine Streptomyces strains by researchers at University of British Columbia, Canada and SCRIPPS in California, USA in 2011. Padanamide is a unique linear peptide featuring three uncommon amino acids, 2-amino-4-ureidobutanoic acid (Auba), and 4-amino-3-hydroxy-2-methyl-5-phenylpentanoic acid (Ahmppa), and two rare but known amino acids, piperazic acid (Pip) and 3β-hydroxyleucine (Hle). Although possessing an unusual structure, padanamide has to date only been shown to exhibit weak antitumor and antimicrobial activity.