title: Novel cytotoxic peptides from the tropical marine cyanobacterium Hormothamnion enteromorphoides. 1. Discovery, isolation and initial chemical and biological characterization of the hormothamnins from wild and cultured material.
abstract: A Caribbean cyanobacterium, Hormothamnion enteromorphoides, was found to produce a complex mixture of ichthyotoxic peptides, perhaps explaining the apparent absence of predation upon these potentially palatable life forms. Bioassay-guided fractionation was used to isolate these toxic and antimicrobial natural products, and a variety of techniques including HR FAB mass spectrometry, 2D-NMR, traditional hydrolysis-amino acid analysis, and several chemical reactions were used to define the basic structural features of the major peptide, hormothamnin A. Hormothamnin A is a cyclic undecapeptide containing six common and five uncommon or new amino acid residues. HPLC analyses indicate that the relative proportions of these peptide natural products remain relatively constant between different collection locations and years, however, they do vary seasonally. Clonal isolates of this cyanobacterium in culture produce the full spectrum of toxic peptides.
authors.affiliation: College of Pharmacy, Oregon State University, Corvallis 97331.
authors.forename: W H
authors.initials: WH
authors.lastname: Gerwick
authors.forename: C
authors.initials: C
authors.lastname: Mrozek
authors.forename: M F
authors.initials: MF
authors.lastname: Moghaddam
authors.forename: S K
authors.initials: SK
authors.lastname: Agarwal
mesh_terms: D000970:Antineoplastic Agents; D001412:Bacillus subtilis / Q000187:drug effects; D002176:Candida albicans / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D000458:Cyanobacteria / Q000032:analysis*; D009682:Magnetic Resonance Spectroscopy; D008387:Marine Toxins; D010456:Peptides, Cyclic / Q000302:isolation & purification* / Q000494:pharmacology; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D008387:Marine Toxins; D010456:Peptides, Cyclic; C058730:hormothamnin A