title: Hepatotoxin (microcystin) and neurotoxin (anatoxin-a) contained in natural blooms and strains of cyanobacteria from Japanese freshwaters.
abstract: Amounts of hepatotoxic microcystin and neurotoxic anatoxin-a were estimated in natural blooms and strains of cyanobacteria from freshwaters in Japan. A simultaneous analysis method of anatoxin-a and microcystin was applied to natural bloom samples, which has been dominated by several species and the strains of cyanobacteria which produced simultaneously both toxins. The natural blooms examined in the present study were mainly composed of Anabaena and Oscillatoria, but most also contained Microcystis and other cyanobacteria. Only one sample was almost unialgal, Anabaena spiroides, collected from Lake Sagami. The toxins in 14 samples collected from nine different natural blooms during 1988-1992 were identified as microcystins-RR, -YR, and -LR; desmethyl-7-microcystin-LR (7-DMLR); and anatoxin-a. Microcystins were the main toxins contained in these natural blooms, with anatoxin-a not being detected or of very little quantity. 7-DMLR was detected in samples only from Lake Kasumigaura. Five strains of Anabaena isolated from waters in Japan produced a small amount of anatoxin-a, but no microcystins. One half of the strains of Microcystis produced microcystins and/or anatoxin-a. This is the first study showing Microcystis producing both anatoxin-a and microcystins.
authors.affiliation: Department of Hygiene, School of Medicine, Shinshu University, Matsumoto, Japan.
authors.forename: H D
authors.initials: HD
authors.lastname: Park
authors.forename: M F
authors.initials: MF
authors.lastname: Watanabe
authors.forename: K
authors.initials: K
authors.lastname: Harda
authors.forename: H
authors.initials: H
authors.lastname: Nagai
authors.forename: M
authors.initials: M
authors.lastname: Suzuki
authors.forename: M
authors.initials: M
authors.lastname: Watanabe
authors.forename: H
authors.initials: H
authors.lastname: Hayashi
mesh_terms: D000595:Amino Acid Sequence; D001427:Bacterial Toxins / Q000032:analysis*; D000458:Cyanobacteria / Q000472:pathogenicity*; D000087522:Cyanobacteria Toxins; D005618:Fresh Water; D007564:Japan; D008387:Marine Toxins / Q000032:analysis*; D052998:Microcystins; D008969:Molecular Sequence Data; D010456:Peptides, Cyclic / Q000032:analysis*; D014326:Tropanes; D014871:Water Microbiology
chemical_list: D001427:Bacterial Toxins; D000087522:Cyanobacteria Toxins; D008387:Marine Toxins; D052998:Microcystins; D010456:Peptides, Cyclic; D014326:Tropanes; C065685:microcystin YR; C509783:anatoxin a; C063855:microcystin RR; C057862:cyanoginosin LR