Enhanced Manganese Oxidation at the Biofilm–Fluid Interface Drives Pore-Scale Patterns in Mineral Precipitation
Year: 2025
Type: article
Abstract: High Resolution Image Download MS PowerPoint Slide Microbial oxidation of manganese (Mn) from aqueous Mn(II) to solid-phase Mn(III, IV) minerals catalyzes Mn(II) removal in natural and engineered porous systems. However, little is known about the spatiotemporal evolution of Mn biomineralization in confined spaces that experience simultaneous Mn(II) delivery and Mn oxide precipitation. Here, we combine time-lapse microscopy, image analysis, and mass spectrometry to quantify the extent and rate of Mn biomineralization by Pseudomonas putida GB-1 in an optically transparent two-dimensional porous medium. We found that Mn(II) oxidation initially occurred within biofilms but shifted over time toward the edges of biofilms in contact with pore fluid. Minerals precipitated outside of the initial biofilm footprint likely due to surface-mediated oxidation of Mn(II) by nascent biogenic Mn oxides, reinforcing a gradient in mineral accumulation from the Mn(II) source near the reactor inlet to the outlet. The rate of mineral precipitation outside the biofilm footprint surpassed the rate of mineral accumulation inside biofilms within 6 h and accounted for two-thirds of the total Mn oxide mass in the pore space at the end of the experiment. This work advances a mechanistic understanding of coupled biotic and abiotic Mn oxidation in porous environments while providing a novel platform to quantify microbe–mineral–fluid interactions.
Authors: Eleanor C. Fadely, Gaitan Gehin, Sharon E. Bone, Samuel M. Webb, Verónica L. Morales, Jasquelin Peña
Language: English
Subfield: Geochemistry and Petrology
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,500
Funders: National Science Foundation, U.S. Department of Energy, Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Office of Science, University of California, Davis, Division of Engineering Education and Centers, Division of Earth Sciences, Basic Energy Sciences, SLAC National Accelerator Laboratory
Awards: G1229526393, SEES: Community Driven Management of Synchrotron Facilities for Earth and Environmental Science, G1286251239, MCA: Geosymbiotic interactions as innovation in Earth and environmental systems: Feedbacks between biological activity, chemical gradients and mineral phases at the pore scale, G2371548206, G2437768688, G2613240575, G262532246, G4235786860, G4654690619, G495301720, G498139845, G5570207115, G5570565201, G6550344761, G7283024673, CAREER: Fundamental Controls of Transport Attributes from Porous Media Microstructure, G8382000481, Engineering Research Center for Bio-mediated and Bio-inspired Geotechnics (CBBG), Electron flows across organo-microbe-mineral units and impact on soil carbon cycling, G911061179, G969889393
OpenAlex ID: W4417535772