Fig. 3.

Relative abundance and diversity of isoA genes in enriched environmental samples revealed by amplicon sequencing. isoA amplicon yielded an average of 12,453 quality-filtered reads per sample. After analysis with the DADA2 pipeline [60] a final set of 134 unique OTUs was obtained (Additional file 2: Table S6). Only OTUs with ≥ 1% abundance in at least one of the samples are represented. For relative abundance of individual OTUs in each enriched environmental sample, see Additional file 1: Figure S3. For α-diversity of enriched environmental samples estimated using Shannon index, see Additional file 1: Table S7