Supplementary Data to:"Extracellular Enzymes Facilitate Electron Uptake in Biocorrosion and Bioelectrosynthesis" doi: 10.1128/mBio.00496-15
Supplementary data to the article: "Extracellular Enzymes Facilitate Electron Uptake in Biocorrosion and Bioelectrosynthesis"
Direct, mediator-free transfer of electrons between a microbial cell and a solid phase in its surrounding environment has been suggested to be a widespread and ecologically significant process. The high rates of microbial electron uptake observed during microbially influenced corrosion of iron [Fe(0)] and during microbial electrosynthesis have been considered support for a direct electron uptake in these microbial processes. However, the underlying molecular mechanisms of direct electron uptake are unknown. We investigated the electron uptake characteristics of the Fe(0)-corroding and electromethanogenic archaeon Methanococcus maripaludis and discovered that free, surface-associated redox enzymes, such as hydrogenases and presumably formate dehydrogenases, are sufficient to mediate an apparent direct electron uptake. In genetic and biochemical experiments, we showed that these enzymes, which are released from cells during routine culturing, catalyze the formation of H2 or formate when sorbed to an appropriate redox-active surface. These low-molecular-weight products are rapidly consumed by M. maripaludis cells when present, thereby preventing their accumulation to any appreciable or even detectable level. Rates of H2 and formate formation by cell-free spent culture medium were sufficient to explain the observed rates of methane formation from Fe(0) and cathode-derived electrons by wild-type M. maripaludis as well as by a mutant strain carrying deletions in all catabolic hydrogenases. Our data collectively show that cell-derived free enzymes can mimic direct extracellular electron transfer during Fe(0) corrosion and microbial electrosynthesis and may represent an ecologically important but so far overlooked mechanism in biological electron transfer.
|Type of resource
|April 21, 2015
|Deutzmann, Joerg S.
|Spormann, Alfred M.
|Deutzmann, Joerg S. and Sahin, Merve and Spormann, Alfred M.. (2015). Supplementary Data to:"Extracellular Enzymes Facilitate Electron Uptake in Biocorrosion and Bioelectrosynthesis" mBio 6:2 e00496-15; Published 21 April 2015, doi: 10.1128/mBio.00496-15 6:2 e00496-15; Published 21 April 2015, doi:10.1128/mBio.00496-15
|Hydrogenase-independent uptake and metabolism of electrons by the archaeon Methanococcus maripaludis ST Lohner, JS Deutzmann, BE Logan, J Leigh, AM Spormann The ISME journal 8 (8), 1673-1681
- Use and reproduction
- User agrees that, where applicable, content will not be used to identify or to otherwise infringe the privacy or confidentiality rights of individuals. Content distributed via the Stanford Digital Repository may be subject to additional license and use restrictions applied by the depositor.
- Preferred Citation
- Deutzmann, Joerg S. and Sahin, Merve and Spormann, Alfred M.. (2015). Supplementary Data to:"Extracellular Enzymes Facilitate Electron Uptake in Biocorrosion and Bioelectrosynthesis" doi: 10.1128/mBio.00496-15. Stanford Digital Repository. Available at: http://purl.stanford.edu/cf407nc0213
Stanford Research DataView other items in this collection in SearchWorks
Also listed in
Loading usage metrics...