title: 16S rRNA gene amplicon sequencing of a methane-rich lake hypolimnion: Extraction Blank
design: 60 mL of ultrapure water was filtered through a 0.22 micron Sterivex-GV Pressure filter as a negative control for extraction. DNA was extracted from the filter using a phenol-chloroform extraction method adapted for Sterivex-GV Pressure filters. The V4 region of the 16S rRNA gene (Earth Microbiome Project (EMB) Caporaso 515F and 806R primers) was amplified by polymerase chain reaction (PCR) with the EMB Illumina 16S amplicon protocol at the UT Genomics Core (The Center for Environmental Biotechnology at the University of Tennessee in Knoxville). The amplified 16S rRNA PCR products were prepared with an Illumina DNA prep kit and then sequenced at the UT Genomics Core using an Illumina Miseq.