Marlow, JeffreySpietz, RachelKim, Keun-YoungEllisman, MarkGirguis, PeterHatzenpichler, Roland2022-06-102022-06-102021-08J. Marlow, R. Spietz, K.-.Y. Kim, M. Ellisman, P. Girguis, R. Hatzenpichler. 2021. "Spatially resolved correlative microscopy and microbial identification reveal dynamic depth- and mineral-dependent anabolic activity in salt marsh sediment.." Environ Microbiol, Volume 23, Issue 8, pp. 4756 - 4777. https://doi.org/10.1111/1462-2920.156671462-2920https://hdl.handle.net/2144/44716Coastal salt marshes are key sites of biogeochemical cycling and ideal systems in which to investigate the community structure of complex microbial communities. Here, we clarify structural-functional relationships among microorganisms and their mineralogical environment, revealing previously undescribed metabolic activity patterns and precise spatial arrangements within salt marsh sediment. Following 3.7-day in situ incubations with a non-canonical amino acid that was incorporated into new biomass, samples were resin-embedded and analysed by correlative fluorescence and electron microscopy to map the microscale arrangements of anabolically active and inactive organisms alongside mineral grains. Parallel sediment samples were examined by fluorescence-activated cell sorting and 16S rRNA gene sequencing to link anabolic activity to taxonomic identity. Both approaches demonstrated a rapid decline in the proportion of anabolically active cells with depth into salt marsh sediment, from ~60% in the top centimetre to 9.4%-22.4% between 2 and 10 cm. From the top to the bottom, the most prominent active community members shifted from sulfur cycling phototrophic consortia, to putative sulfate-reducing bacteria likely oxidizing organic compounds, to fermentative lineages. Correlative microscopy revealed more abundant (and more anabolically active) organisms around non-quartz minerals including rutile, orthoclase and plagioclase. Microbe-mineral relationships appear to be dynamic and context-dependent arbiters of biogeochemical cycling.p. 4756 - 4777© 2021 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.© 2021 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.Article10.1111/1462-2920.15667638451