Quantification of select cyanobacteria and cyanotoxins in Piedmont North Carolina lakes using real-Time PCR

Cyanobacteria species are distributed worldwide and extensive growth can result in cyanotoxin production, hypoxic zones, human health risk, and mortality of fish, domesticated animals, invertebrates, and plants. Better analytical tools can help water quality managers and regulatory agencies assess and manage cyanobacteria and cyanotoxin abundance to reduce environmental and health risk. This study determined the presence and relative abundance of 4 potentially toxic cyanobacteria taxa (Microcystis aeruginosa, Cylindrospermopsis raciborskii, Lyngbya wollei, and Aphanizomenon/ Anabaena spp.), total cyanobacteria, and three toxin genes (microcystin mcyH+/A-, cylindrospermopsin PKS, and anatoxin PKS) using qPCR, and concentrations of microcystin and cylindrospermopsins in selected samples using ELISA assays. All species were found in all lakes, but abundance of individual taxa SSU rDNA and toxin genes differed among lakes. Microcystins were found at low levels (=0.31ppb) in 4 of the 6 lakes sampled, but were not correlated with mcyH+/A- abundance. The anatoxin PKS gene was found in all lakes sampled and was significantly correlated with Aphanizomenon/ Anabaena spp. SSU rDNA in two of the lakes. The cylindrospermopsin PKS gene and cylindrospermopsins were not found in any of the lakes sampled.