title: Tunichrome sp-1: new pentapeptide tunichrome from the hemocytes of Styela plicata.
abstract: A modified pentapeptide has been isolated from the hemocytes of the ascidian Styela plicata. The structure of the peptide was determined by Edman sequence analysis, mass spectrometry, and NMR spectroscopy with the stereochemistry assigned by acid hydrolysis followed by both (a) GC-MS of the volatile amino acid derivatives on a chiral column and (b) ultrasensitive detection of fluorescent diasteromeric derivatives of the component amino acids after reversed-phase HPLC. The peptide L-DOPA-L-DOPA-Gly-L-Pro-dcdeltaDOPA (where DOPA = 3,4-dihydroxyphenylalanine and dcdeltaDOPA = decarboxy-(E)-alpha,beta-dehydro-3,4-dihydroxyphenylalanine) we designate as tunichrome Sp-1.
authors.affiliation: Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093-0204, USA.
authors.forename: J Andy
authors.initials: JA
authors.lastname: Tincu
authors.forename: Steven W
authors.initials: SW
authors.lastname: Taylor
mesh_terms: D000596:Amino Acids / Q000032:analysis / Q000737:chemistry; D000818:Animals; D002140:California; D002851:Chromatography, High Pressure Liquid; D004926:Escherichia coli / Q000187:drug effects; D008401:Gas Chromatography-Mass Spectrometry; D006868:Hydrolysis; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D009842:Oligopeptides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D013056:Spectrophotometry, Ultraviolet; D013211:Staphylococcus aureus / Q000187:drug effects; D013237:Stereoisomerism; D014561:Urochordata / Q000737:chemistry*
chemical_list: D000596:Amino Acids; D009842:Oligopeptides; C455663:tunichrome sp-1