Supplementary datasets for Howells et al., "Methanotrophy Under Extreme Alkalinity in a Serpentinizing System"

Supplementary materials for Howells et al. (2026) containing geochemical and biological datasets. For a detailed description of data collection, please read Howells et al. (2026). Below are captions for each supplementary table and file. Howells, A.E.G., Robinson, K., Silva, M.G. et al. Methanotrophy under extreme alkalinity in a serpentinizing system. Nat Commun (2026). https://doi.org/10.1038/s41467-026-72513-6 Supplementary Data 1. Concentrations of reactants and products for methane oxidation coupled to O2, NO3- and SO3-2. Estimated energy availability in unite kJ per mole electron and kJ per kg fluid. Supplementary Data 2. Core methanotroph metabolism genes, annotations and BLASTp results. Supplementary Data 3. Descriptive statistics and Mann-Whitney U test parameters to assess the significance of distribution differences of aerobic methanotroph phylotypes with respect to total ammonia nitrogen (TAN). Supplementary Data 4. ASVs classified as methanotrophs, the taxonomic assignment and BLASTn results. Supplementary Data 5. Relative abundance of ASVs classified as methanotrophs. Supplementary Data 6. Relative abundance of methanotroph phylotypes by group. Supplementary Data 7. Bin39 metabolic pathway overview from DRAM annotation. Supplementary Code 1. .faa file for coding sequences of Bin39 and their DRAM annotations.