Churro, CatarinaPereira, PauloVasconcelos, VitorValério, Elisabete2012-11-262012-11-262012-09Arch Microbiol. 2012 Sep;194(9):749-57. Epub 2012 Apr 7.0302-8933doi: 10.1007/s00203-012-0809-yhttp://hdl.handle.net/10400.18/1119A species-specific method to detect and quantify Planktothrix agardhii was developed by combining the SYBR Green I real-time polymerase chain reaction technique with a simplified DNA extraction procedure for standard curve preparation. Newly designed PCR primers were used to amplify a specific fragment within the rpoC1 gene. Since this gene exists in single copy in the genome, it allows the direct achievement of cell concentrations. The cell concentration determined by real-time PCR showed a linear correlation with the cell concentration determined from direct microscopic counts. The detection limit for cell quantification of the method was 8 cells μL−1, corresponding to 32 cells per reaction. Furthermore, the real-time qPCR method described in this study allowed a successful quantification of P. agardhii from environmental water samples, showing that this protocol is an accurate and economic tool for a rapid absolute quantification of the potentially toxic cyanobacterium P. agardhii.engCyanobacteriaPlanktothrix AgardhiiReal-time qPCRrpoC1 GeneÁgua e Solojournal article