Figure 7.
16S rDNA phylogenetic tree of enrichment culture isolates and reference species. 16S rRNA genes were amplified using primers 8F and 1510R (Table 3) and sequenced from a pCR4-TOPO clone library (Invitrogen). Chimeric, low-quality, and redundant sequences were removed. 28 sequences from enrichment cultures and 12 reference sequences were aligned with MUSCLE.70 The alignment was manually trimmed to yield a final length of 1371 bp and a maximum likelihood tree was constructed in MEGA767 using the Tamura–Nei method of substitution.71 Bootstrap values from 50 to 100% are displayed. The highest similarity score calculated by RDP SeqMatch was used to assign the lowest classification level for each enrichment isolate.72 The full-length sequences obtained for this analysis have been deposited in GenBank (accession: MG367094-MG367121).