SONG Lirong, PAN Hui, LEI Lamei, LIU Yongding, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, P.R. China

Abstract

Based on the evidence that the mcyB gene is closely associated with microcystin biosynthesis, we surveyed the distribution of this gene in different cyanobacteria and then differentiate toxic strains from nontoxic ones. Furthermore, PCR protocol was simplified by using intact cyanobacteria cells in culture, in water and in sediment samples, which made the detection more efficient and more sensitive. Thus, it is possible to discriminate toxic and non-toxic strains of Microcystis both in culture and in environmental sample directly. This method is sensitive enough to detect targeted mcyB gene in samples with less than 2000 Microcystis cells per mL. Results of HPLC, ELISA and mouse bioassay as well as sequences of amplifications confirmed the accuracy, specify and applicability of PCR using whole cyanobacteria cells.