title: Isolation and characterization of microcystins from laboratory cultures and environmental samples of Microcystis aeruginosa and from an associated animal toxicosis.
abstract: Six microcystins were identified in a laboratory culture of the cyanobacterium (blue-green alga) Microcystis aeruginosa PCC 7813 using high-performance liquid chromatography coupled with diode array detection (HPLC-DAD) and mass spectrometry (LC-MS). The toxins were purified and further characterized by amino acid analysis and tandem mass spectrometry (MS-MS). The presence of the previously reported microcystin-LR and microcystin-LY was confirmed. Two further microcystins were characterized as microcystin-LW and microcystin-LF. Another two toxins were partially characterized and are believed to be an analog of microcystin-LR (molecular weight 1008) and microcystin-LM (molecular weight 969). Natural bloom material of M. aeruginosa collected from 2 reservoirs was found to have similar microcystin profiles using HPLC-DAD and LC-MS, indicating the widespread occurrence of these microcystin variants. In addition, the presence of 5 of the microcystins was confirmed in the rumen contents of a lamb by LC-MS and LC-MS-MS, providing the first report of microcystins identified in an animal suspected of being poisoned by cyanobacterial hepatotoxins.
authors.affiliation: Department of Biological Sciences, University of Dundee, United Kingdom.
authors.forename: L A
authors.initials: LA
authors.lastname: Lawton
authors.forename: C
authors.initials: C
authors.lastname: Edwards
authors.forename: K A
authors.initials: KA
authors.lastname: Beattie
authors.forename: S
authors.initials: S
authors.lastname: Pleasance
authors.forename: G J
authors.initials: GJ
authors.lastname: Dear
authors.forename: G A
authors.initials: GA
authors.lastname: Codd
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D056486:Chemical and Drug Induced Liver Injury; D002851:Chromatography, High Pressure Liquid; D004285:Dogs; D006868:Hydrolysis; D008107:Liver Diseases / Q000662:veterinary*; D013058:Mass Spectrometry; D052998:Microcystins; D046931:Microcystis / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D010456:Peptides, Cyclic / Q000032:analysis* / Q000302:isolation & purification / Q000506:poisoning*; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors*; D012417:Rumen / Q000737:chemistry; D012756:Sheep; D012757:Sheep Diseases / Q000139:chemically induced*; D014873:Water Pollutants / Q000032:analysis* / Q000302:isolation & purification / Q000506:poisoning*
chemical_list: D000596:Amino Acids; D052998:Microcystins; D010456:Peptides, Cyclic; D014873:Water Pollutants; C078588:microcystin; D010749:Phosphoprotein Phosphatases