Fig. 1: The estimated relative abundances of Methanobacterium MAGs in communities from subsurface fracture waters collected from wells intersecting the Samail Ophiolite in 2017 (A) and phylogenomic reconstruction of Oman methanogen metagenome assembled genomes (MAGs) in relation to representative Methanobacterium genomes (B).

In A, wells are listed in order of ascending pH from left to right with pH values indicated below the name of each well in parentheses. Contigs with ≥98% nucleotide identity to the Methanobacterium Type I MAG from WAB188 were classified as Type I and contigs with ≥98% nucleotide identity to the Methanobacterium Type II MAG from NSHQ14C were classified as Type II. Estimated relative abundances are shown as the number of reads affiliated with Methanobacterium Type I or II MAGs as a percentage of the total reads in each metagenome. In B, pink text depicts the Type I MAG and cyan text depicts Type II MAGs. All bootstrap values of displayed nodes are >980 out of 1000 bootstrap replicates. Clade-level triangles indicate the phylogenetic diversity within each group via side lengths that are proportional to the distances between the clade’s most closely related and furthest related taxa. Branch length is relative to the scale provided at the bottom of the figure indicating the expected number of substitutions per site. Filled boxes to the right of terminals indicate the presence of genes in reconstructed MAGs or genomes, whereas empty boxes indicate absence of genes in reconstructed MAGs or genomes. Frh coenzyme F₄₂₀-reducing (Group 3a) [NiFe]-hydrogenase, Mvh methyl viologen (Group 3c) [NiFe]-hydrogenase, Mrp-Mbh multiple resistance and pH adaptation module—membrane-bound (Group 4) [NiFe]-hydrogenase protein complex.