Carbon quantity and quality drives variation in cave microbial communities and regulates Mn(II) oxidation
| Autor: | Michael A. Carson, Mara L. C. Cloutier, Suzanna L. Bräuer, Michael D. Madritch, Sarah K. Carmichael |
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| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
biology Ecology Microorganism chemistry.chemical_element Manganese Multicopper oxidase biology.organism_classification 03 medical and health sciences 030104 developmental biology chemistry Manganese peroxidase Environmental chemistry Environmental Chemistry Ecosystem Carbon Bacteria Earth-Surface Processes Water Science and Technology Archaea |
| Zdroj: | Biogeochemistry. 134:77-94 |
| ISSN: | 1573-515X 0168-2563 |
| Popis: | Cave ecosystems are carbon limited and thus are particularly susceptible to anthropogenic pollution. Yet, how carbon quality and quantity that can modulate the pathways and amount of Mn cycling in caves remains largely unknown. To explore Mn cycling, baseline bacterial, archaeal, and fungal communities associated with Mn(III/IV) oxide deposits were assessed in both relatively ‘pristine’ and anthropogenically impacted caves in the Appalachian Mountains (USA). Cave sites were then amended with various carbon sources that are commonly associated with anthropogenic input to determine whether they stimulate biotic Mn(II) oxidation in situ. Results revealed patterns between sites that had long-term exogenous carbon loading compared to sites that were relatively ‘pristine,’ particularly among Bacteria and Archaea. Carbon treatments that stimulated Mn(II) oxidation at several sites resulted in significant changes to the microbial communities, indicating that anthropogenic input can not only enhance biotic Mn(II) oxidation, but also shape community structure and diversity. Additional carbon sources amended with copper were incubated at various cave sites to test the role that Cu(II) plays in in situ biotic Mn(II) oxidation. Media supplemented with 100 µM Cu(II) inhibited bacterial Mn(II) oxidation but stimulated fungal Mn(II) oxidation, implicating fungal use of multicopper oxidase (MCO) enzymes but bacterial use of superoxide to oxidize Mn(II). In sites with low C:N ratios, the activity of the Mn(II) oxidizing enzyme manganese peroxidase (MnP) appears to be limited (particularly by MnP-utilizing Basidiomycetes and/or Zygomycetes). |
| Databáze: | OpenAIRE |
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