Improved real-time PCR estimation of gene copy number in soil extracts using an artificial reference

Abstract
Application of Polymerase Chain Reaction (PCR) techniques has developed significantly from a qualitative technology to include powerful quantitative technologies, including real-time PCR, which are regularly used for detection and quantification of nucleic acids in many settings, including community analysis where culture-based techniques are not suitable. Many applications of real-time PCR involve absolute quantification which is susceptible to inaccuracies caused by losses during DNA extraction or inhibition caused by co-extracted compounds. We present here an improvement to this approach involving the addition of an artificial internal standard, prior to nucleic acid extraction. By estimating gene target copies by relative abundance, this approach accounts for both loss during extraction and inhibition effects. We present a novel application of relative real time PCR allowing accurate estimation of total bacterial populations both within and across a wide range of soils and demonstrate its improvement over absolute quantification by comparison of both approaches to ELFA analysis of the same soils.
Year
2012
Category
Refereed journal
Output Tags
WP3.3 - The soil, water and air interface and its response to change