Article

Diverse taxa of cyanobacteria produce beta-N-methylamino-L-alanine, a neurotoxic amino acid.

Institute for Ethnomedicine, National Tropical Botanical Garden, Kalaheo, HI 96741, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 05/2005; 102(14):5074-8. DOI: 10.1073/pnas.0501526102
Source: PubMed

ABSTRACT Cyanobacteria can generate molecules hazardous to human health, but production of the known cyanotoxins is taxonomically sporadic. For example, members of a few genera produce hepatotoxic microcystins, whereas production of hepatotoxic nodularins appears to be limited to a single genus. Production of known neurotoxins has also been considered phylogenetically unpredictable. We report here that a single neurotoxin, beta-N-methylamino-L-alanine, may be produced by all known groups of cyanobacteria, including cyanobacterial symbionts and free-living cyanobacteria. The ubiquity of cyanobacteria in terrestrial, as well as freshwater, brackish, and marine environments, suggests a potential for wide-spread human exposure.

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