Identification and toxigenic potential of a cyanobacterial strain (Stigomena sp.)

Cyanobacteria are well known for their production of a multitude of highly toxic substances . The genus Stigomena is regarded as good candidates for producing biologically active secondary metabolites, which are highly toxic to humans and other animals. The carcass of a dog was found at the shore of Lake Ali-Abad, Iran. Biomass from the discovery site appeared to be of cyanobacterial nature. We identified the strain as freshwater bloom-forming representative of the Stigomena genus on the basis of its 16S rRNA sequence. It carried the mcyE gene, as well as a potential cryptic hassallidin gene cluster. These results suggest that microcystin-induced liver damage may have significantly ontributed to the death of the dog. This case is thus the first reported incident of potential microcystin intoxication in a dog in Iran.