Influence of PCR cycle number on 16S rRNA gene amplicon sequencing of low biomass samples.

The objective of this study was to evaluate the effects of increased PCR cycle number on sequencing results from samples with low microbial biomass, including bovine milk, and murine pelage and blood. We hypothesized that subjecting DNA from such samples to higher PCR cycle numbers would increase 16S rRNA sequencing coverage. DNA was extracted from matched samples of each type and multiple PCR cycle numbers were evaluated to generate a total of 96 libraries from 24 milk samples, 46 libraries from 23 pelage samples, and 170 libraries from 85 blood samples.