Fig. 5: Phylogenetic tree of the putative mercury reductase gene (merA).

Binned and unbinned sequences identified in the metagenomic dataset by the bioinformatic pipeline are in bold. The tree was rooted with alkylmercury lyase gene (merB) sequences. Due to sequence proximity with other genes of the pyrimidine nucleotide disulfide oxidoreductase family (pndr, dld), multiple incorrect assignments to putative merA genes were identified. Bootstraps >0.8 were represented by gray points.