Amplicon sequencing of negative control 2 kit 1. Sequencing was performed as described in https://doi.org/10.3389/fmicb.2021.669776. {primers: GTGYCAGCMGCCGCGGTAA + GGACTACNVGGGTWTCTAAT, nucleic acid: DNA, flow cell identifier: JV7P3, barcoding: UDB-H12, plate-position: 2 B1, barcodes: CCTTCAATGGGA + CCTTTATAGTCC}.