Fig. 3.

Phylogeny and relative abundance of the CODH-OTUs amplified by the new primer sets from the environmental and enriched samples. The tree was constructed using an alignment of 1558 CODH proteins and the CODH-OTUs. Major clades B through F are indicated on the right. FirmiCODHech subclades are assigned and colored in red. The colors of branches and leaves indicate the following: red, FirmiCODHechs; black, other CODHs; other colors, CODH-OTUs amplified by each new primer set. The relative abundances of CODH-OTUs in each primer set are shown in the bubble plot with different colors to the right of the tree. Asterisks indicate novel CODH-OTUs showing < 94.5% pairwise nucleotide sequence identity with the closest CODHech gene. The black squares on the branch indicate > 0.8 support by bootstrap values