Use of the SYBR Green I fluorescent dye and a centrifugal filter device for rapid determination of dissolved DNA concentration in fresh water

K Matsui, N Ishii, M Honjo, Z Kawabata
2004 Aquatic Microbial Ecology  
A rapid fluorometric assay using the fluorescent dye SYBR Green I was established to determine the concentration of dissolved nucleic acids in fresh water. The sensitivity of SYBR Green I to double stranded DNA (dsDNA) (λHin d III digest) was as low as 50 pg, 200 times more sensitive than Hoechst 33258. SYBR Green I bound to dsDNA emitted 10 times stronger fluorescence than when bound to single stranded DNA or RNA, indicating its selectivity for dsDNA measurement. The dissolved DNA (dDNA)
more » ... ed DNA (dDNA) concentration in fresh water determined using SYBR Green I was almost the same as that obtained using Hoechst 33258. This suggests that the dDNA measured by SYBR Green I is comparable to that determined by Hoechst 33258 in previous studies. To reduce preparation time, the dDNA in lake water filtrate was precipitated by ethanol and purified using a centrifugal filter device. The overall preparation process takes only a few hours and requires only 10 ml of water. The process described here may, therefore, facilitate 'same day' measurement of dDNA dynamics in freshwater environments. KEY WORDS: Dissolved DNA · SYBR Green I · Ethanol precipitation · Centrifugal filter device · Extracellular DNA · Fresh water Resale or republication not permitted without written consent of the publisher
doi:10.3354/ame036099 fatcat:ip6apzoqeved5bff44iyrqeqde