RESUMEN

[D-Leu1]Microcystin-LR was identified as the most abundant microcystin from a laboratory strain of the cyanobacterium Microcystis sp. isolated from a hepatotoxic Microcystis bloom from brackish waters in the Patos Lagoon estuary, southern Brazil. Toxicity of [D-Leu1]microcystin-LR, according to bioassay and protein phosphatase inhibition assay, was similar to that of the commonly-occurring microcystin-LR, which was not detectable in the Patos Lagoon laboratory isolate. This is the first report of a microcystin containing [D-Leu1] in the cyclic heptapeptide structure of these potent cyanobacterial toxins.

Asunto(s)

Microcystis/química , Péptidos Cíclicos/aislamiento & purificación , Brasil , Espectroscopía de Resonancia Magnética , Microcistinas , Microcystis/crecimiento & desarrollo , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Péptidos Cíclicos/química , Espectrometría de Masa Bombardeada por Átomos Veloces