[HTML][HTML] FungiQuant: a broad-coverage fungal quantitative real-time PCR assay

CM Liu, S Kachur, MG Dwan, AG Abraham, M Aziz… - BMC microbiology, 2012 - Springer
CM Liu, S Kachur, MG Dwan, AG Abraham, M Aziz, PR Hsueh, YT Huang, JD Busch
BMC microbiology, 2012Springer
Background Fungal load quantification is a critical component of fungal community
analyses. Limitation of current approaches for quantifying the fungal component in the
human microbiome suggests the need for new broad-coverage techniques. Methods We
analyzed 2,085 18S rRNA gene sequences from the SILVA database for assay design. We
generated and quantified plasmid standards using a qPCR-based approach. We evaluated
assay coverage against 4,968 sequences and performed assay validation following the …
Background
Fungal load quantification is a critical component of fungal community analyses. Limitation of current approaches for quantifying the fungal component in the human microbiome suggests the need for new broad-coverage techniques.
Methods
We analyzed 2,085 18S rRNA gene sequences from the SILVA database for assay design. We generated and quantified plasmid standards using a qPCR-based approach. We evaluated assay coverage against 4,968 sequences and performed assay validation following the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines.
Results
We designed FungiQuant, a TaqMan® qPCR assay targeting a 351 bp region in the fungal 18S rRNA gene. Our in silico analysis showed that FungiQuant is a perfect sequence match to 90.0% of the 2,617 fungal species analyzed. We showed that FungiQuant’s is 100% sensitive and its amplification efficiencies ranged from 76.3% to 114.5%, with r 2 -values of >0.99 against the 69 fungal species tested. Additionally, FungiQuant inter- and intra-run coefficients of variance ranged from <10% and <20%, respectively. We further showed that FungiQuant has a limit of quantification 25 copies and a limit of detection at 5 copies. Lastly, by comparing results from human-only background DNA with low-level fungal DNA, we showed that amplification in two or three of a FungiQuant performed in triplicate is statistically significant for true positive fungal detection.
Conclusions
FungiQuant has comprehensive coverage against diverse fungi and is a robust quantification and detection tool for delineating between true fungal detection and non-target human DNA.
Springer