Plicatamide: A lead to the biosynthetic origins of the tunichromes?
Plicatamide is a modified octapeptide from the ascidian Styela plicata having the structure Phe-Phe-His-Leu-His-Phe-His-decarboxyDeltaDOPA (where decarboxyDeltaDOPA = decarboxy-(E)-alpha,beta-dehydro-3, 4-dihydroxyphenylalanine). Edman sequencing, tandem mass spectrometry, and proton NMR have been used to characterize 100 microg of the compound. Plicatamide represents an important link between two classes of biomolecules: the tunichromes which share an oxidatively decarboxylated C-terminus and higher molecular weight DOPA-polypeptides. The 8-residue sequence provides the first opportunity to investigate the biosynthetic origins of the tunichrome family by molecular biological techniques.
Tincu
J A
JA
Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093-0204, USA.
Craig
A G
AG
Taylor
S W
SW
D000595:Amino Acid Sequence; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D009842:Oligopeptides / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D009930:Organic Chemicals; D010860:Pigments, Biological / Q000096:biosynthesis*; D014561:Urochordata / Q000378:metabolism*
D009842:Oligopeptides; D009930:Organic Chemicals; D010860:Pigments, Biological; C407359:plicatamide; C021765:tunichrome