title: 16S (V4) marker-gene survey of anaerobic digester community digesting switchgrass at 5d retention time, 37 C, and pH 5.5: reactor 9, replicate 2
design: DNA was extracted from approximately 150 mg wet mass of reactor contents by adding directly to the bead lysing tube of a Qiagen DNeasy Powersoil DNA extraction kit, and PCR amplified using the 515FB-806RB primer set (Walters, et al. 2015. mSystems https://doi.org/10.1128/mSystems.00009-15) targeting the V4 variable region of the 16S rRNA gene for bacteria and archaea.  A two-step library preparation was used including the incorporation of illumina overhang adapters onto locus-specific PCR primers, followed by a second round of PCR to add sequencing adapters and sample barcodes using an Illumina Nextera XT Index Kit.