title: Monitoring of geosmin producing Anabaena circinalis using quantitative PCR.
abstract: Geosmin is one of the most commonly detected off-flavor chemicals present in reservoirs and drinking water systems. Quantitative real-time PCR (qPCR) is useful for quantifying geosmin-producers by focusing on the gene encoding geosmin synthase, which is responsible for geosmin synthesis. In this study, several primers and probes were designed and evaluated to detect the geosmin synthase gene in cyanobacteria. The specificity of primer and probe sets was tested using 21 strains of laboratory cultured cyanobacteria isolated from surface waters in Australia (18) and Taiwan (2), including 6 strains with geosmin producing ability. The results showed that the primers designed in this study could successfully detect all geosmin producing strains tested. The selected primers were used in a qPCR assay, and the calibration curves were linear from 5 × 10(1) to 5 × 10(5) copies mL(-1), with a high correlation coefficient (R(2) = 0.999). This method was then applied to analyze samples taken from Myponga Reservoir, South Australia, during a cyanobacterial bloom event. The results showed good correlations between qPCR techniques and traditional methods, including cell counts determined by microscopy and geosmin concentration measured using gas chromatography (GC) coupled with a mass selective detector (MSD). Results demonstrate that qPCR could be used for tracking geosmin-producing cyanobacteria in drinking water reservoirs. The qPCR assay may provide water utilities with the ability to properly characterize a taste and odor episode and choose appropriate management and treatment options.
authors.affiliation: Department of Environmental Engineering, National Cheng Kung University, Tainan 70101, Taiwan, ROC.
authors.forename: Hsiang-Wei
authors.initials: HW
authors.lastname: Tsao
authors.affiliation: Department of Environmental Engineering, National Cheng Kung University, Tainan 70101, Taiwan, ROC.
authors.forename: Atsuko
authors.initials: A
authors.lastname: Michinaka
authors.affiliation: Department of Environmental Engineering, National Cheng Kung University, Tainan 70101, Taiwan, ROC; Department of Biological Science and Technology, Meiho University, Pingtung 91202, Taiwan, ROC.
authors.forename: Hung-Kai
authors.initials: HK
authors.lastname: Yen
authors.affiliation: Australian Water Quality Centre, South Australian Water Corporation, Adelaide, South Australia 5000, Australia.
authors.forename: Steven
authors.initials: S
authors.lastname: Giglio
authors.affiliation: Australian Water Quality Centre, South Australian Water Corporation, Adelaide, South Australia 5000, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Hobson
authors.affiliation: Australian Water Quality Centre, South Australian Water Corporation, Adelaide, South Australia 5000, Australia.
authors.forename: Paul
authors.initials: P
authors.lastname: Monis
authors.affiliation: Department of Environmental Engineering, National Cheng Kung University, Tainan 70101, Taiwan, ROC. Electronic address: tflin@mail.ncku.edu.tw.
authors.forename: Tsair-Fuh
authors.initials: TF
authors.lastname: Lin
mesh_terms: D017033:Anabaena / Q000235:genetics*; D001315:Australia; D004784:Environmental Monitoring; D005798:Genes, Bacterial; D005843:Geography; D009284:Naphthols / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*; D012015:Reference Standards; D013997:Time Factors
chemical_list: D009284:Naphthols; C001278:geosmin
keywords: Anabaena circinalis; Geosmin synthesis gene; Monitoring; Quantitative PCR; Reservoir