16S rRNA library preparation and sequencing
The 16S rRNA libraries were prepared using a Rapid Barcoding Kit 24 V14 (SQK-RBK114.24) (Oxford Nanopore Technologies, UK) according to the manufacturer’s protocol. The 24 barcodes were pooled in equal concentrations. The sequencing was performed using a MinION Flow Cell (R10.4.1) with a GridION sequencer (Oxford Nanopore Technologies, UK).