Search

In South Africa, little is known about the production of microcystin by the genusAnabaenaBory. In April 2012, during a cyanobacterial bloom event in Theewaterskloof Dam, Western Cape province, the plankton was sampled on 10 occasions. The dominant algae belonged to the genusAnabaena, a family of filamentous cyanobacteria known to produce cyanotoxins such as anatoxin-a, harmful to humans and the aquatic foodweb. The specimens isolated lacked the characteristic akinetes and/or heterocysts associated with this genus. Therefore the 16S rRNA gene was Sanger sequenced and a maximum parsimony tree was constructed, confirming its identity asAnabaena ucrainica(Schkorbatow) M. Watanabe. Enzyme-linked immunosorbent assay (ELISA) confirmed the presence of microcystin-LR in the isolatedA. ucrainicafield sample, while PCR analysis and sequencing further confirmed the presence ofmcygenes in this species. It was speculated from the data that prevailing low water-column temperatures and strong gusty winds may have resulted in the lack of akinete or heterocyst production. TheAnabaenastrain isolated from Theewaterskloof Dam is the first report of a strain containing microcystin-LR belonging to this genus in a freshwater body in Africa. [ABSTRACT FROM PUBLISHER]