Microbial DNA was extracted from stool by bead-beating in SDS lysis buffer, heat/precipitation cleanup, RNase/proteinase K treatment, and DNeasy purification. The 16S rRNA V3V4 region was PCR-amplified (341F/785R), cleaned, Nextera-indexed, pooled, and sequenced as 2250 bp on an Illumina MiSeq with 20% PhiX.