Biology subjects

de Moor, J. M.

Publications and source records attributed to de Moor, J. M..

3 recordsLinked to original sources

bioRxiv2026

Global carbon fixation in Earth's subsurface biosphere

The subsurface of our planet hosts 15% of Earths biomass and plays a key role in mediating the exchange of volatiles and elements between deep, long-residence-time geological reservoirs and rapidly cycling surface environments, influencing planetary climate and habitability. While a significant fraction of subsurface microorganisms rely on surface-derived organic carbon, an unknown portion is sustained through chemolithotrophic carbon fixation. Despite its importance, the global diversity and distribution of microbial carbon fixation pathways in the subsurface, and the environmental drivers shaping them, remain poorly constrained. Here we systematically characterise carbon fixation pathways for 412 subsurface metagenomes, including 242 new metagenomes, and compare them to surface-derived datasets. We find that subsurface environments span a broader physicochemical space than surface systems and support a higher abundance and diversity of carbon fixation strategies. Using colocated geochemical data spanning >50 variables, we show that the reductive tricarboxylic acid cycle and the reductive acetyl-CoA pathway are enriched in reducing, geochemically evolved fluids. We use the metagenomic results together with previously published carbon fixation rates in the subsurface to derive a global continental subsurface carbon fixation rate of [~]2.65 Pg C yr-1 (range: 0.31-2.99). This represents [~]2% of terrestrial photosynthetic primary production, and is an order of magnitude higher than geological fluxes between the surface and the subsurface. These results identify the subsurface as a reservoir of autotrophic strategies organized along geochemical gradients, contributing substantially to the global carbon cycle. One Sentence SummaryThe subsurface is a widespread, environmentally and functionally diverse reservoir of autotrophic carbon fixation pathways that can contribute substantially to the global carbon cycle, fixing [~]2.65 Pg C yr-1 in continental settings alone.

microbiology↗

bioRxiv2025

Tectonic setting shapes microbial biosynthetic potential across global geothermal environments

Microbial communities in geothermal environments constitute an underexplored reservoir of biosynthetic gene clusters with significant biotechnological potential. Here, we investigate the secondary metabolite potential of 219 microbial communities across marine and continental geothermal field sites, encompassing broad environmental gradients in temperature (4.7{degrees}C to 93.5{degrees}C), pH (0.85 to 10.3), and tectonic setting, including volcanic arcs, backarcs, divergent margins at on-axis mid-ocean ridges, post-subduction extensional arcs, and paleo-convergent intraplate plume systems. We identified 9,019 putative new biosynthetic gene cluster families, mostly lacking similarity to known biosynthetic gene clusters. Volcanic arc systems consistently exhibit the highest diversity of biosynthetic repertoires, whereas intraplate plume systems showed a greater representation of terpene-associated gene cluster families. In contrast, divergent margin systems were primarily characterized by nonribosomal peptide synthetases and ribosomally synthesized and post-translationally modified peptides pathways, together accounting for a large fraction of their predicted biosynthetic diversity. These findings suggest that tectonic context could be associated with large-scale patterns in microbial biosynthetic potential and provide a geobiological framework for guiding natural product discovery in geothermal ecosystems.

microbiology↗

bioRxiv2023

Complex organic matter degradation by secondary consumers in chemolithoautotrophy-based subsurface geothermal ecosystems

Microbial communities in terrestrial geothermal systems often contain chemolithoautotrophs with well-characterized distributions and metabolic capabilities. However, the extent to which organic matter produced by these chemolithoautotrophs supports heterotrophs remains largely unknown. Here we compared the abundance and activity of peptidases and carbohydrate active enzymes (CAZymes) that are predicted to be extracellular identified in metagenomic assemblies from 63 springs in the Central American and the Andean convergent margin (Argentinian backarc of the Central Volcanic Zone), as well as the plume-influenced spreading center in Iceland. All assemblies contain two orders of magnitude more peptidases than CAZymes, suggesting that the microorganisms more often use proteins for their carbon and/or nitrogen acquisition instead of complex sugars. The CAZy families in highest abundance are GH23 and CBM50, and the most abundant peptidase families are M23 and C26, all four of which degrade peptidoglycan found in bacterial cells. This implies that the heterotrophic community relies on autochthonous dead cell biomass, rather than allochthonous plant matter, for organic material. Enzymes involved in the degradation of cyanobacterial- and algal-derived compounds are in lower abundance at every site, with volcanic sites having more enzymes degrading cyanobacterial compounds and non-volcanic sites having more enzymes degrading algal compounds. Activity assays showed that many of these enzyme classes are active in these samples. High temperature sites (> 80{degrees}C) had similar extracellular carbon-degrading enzymes regardless of their province, suggesting a less well-developed population of secondary consumers at these sites, possibly connected with the limited extent of the subsurface biosphere in these high temperature sites. We conclude that in < 80{degrees}C springs, chemolithoautotrophic production supports heterotrophs capable of degrading a wide range of organic compounds that do not vary by geological province, even though the taxonomic and respiratory repertoire of chemolithoautotrophs and heterotrophs differ greatly across these regions.

biochemistry↗