title: 16S sequencing of Mock community control
design: DNA libraries were prepared by the University of Michigan Microbial Systems Molecular Biology Laboratory.  In brief, the V4 region of the bacterial 16S rRNA gene was amplified using touchdown PCR with barcoded dual-index primers.  The touchdown PCR cycles consisted of 2 min at 95C, followed by 20 cycles of 95C for 20 sec, 60C (starting from 60C, the annealing temperature decreased 0.3C each cycle) for 15 sec and 72C for 5 min, followed by 20 cycles of 95C for 20 sec, 55C for 15 sec and 72C for 5 min and a final 72C for 10 min.  Resulting amplicon libraries were normalized and sequenced on an Illumina sequencing platform using a MiSeq Reagent Kit V2 (Illumina, San Diego, CA, USA).  The final load concentration was 4.0-5.5 pM with a 15% PhiX spike to add diversity.