Biogenic Iron Sulfide Nanoparticles to Enable Extracellular Electron Uptake in Sulfate‐Reducing Bacteria

• Published in: Angewandte Chemie Vol. 132; no. 15; pp. 6051 - 6055
• Main Authors: Deng, Xiao, Dohmae, Naoshi, Kaksonen, Anna H., Okamoto, Akihiro
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 06.04.2020; Wiley Blackwell (John Wiley & Sons)
• Subjects: Bacteria; Bioelektrochemie; Cell surface; Chemistry; Electrodes; Electrons; Extrazelluläre Elektronenaufnahme; FeS-Nanopartikel; Iron; Iron sulfides; Massenspektrometrie; Metabolic rate; Metabolism; Nanoparticles; Physicochemical properties; Sulfate reduction; Sulfatereduzierende Bakterien; Sulfates
• ISSN: 0044-8249; 1521-3757
• DOI: 10.1002/ange.201915196

Microbes synthesize cell‐associated nanoparticles (NPs) and utilize their physicochemical properties to produce energy under unfavorable metabolic conditions. Iron sulfide (FeS) NPs are ubiquitous and are predominantly biosynthesized by sulfate‐reducing bacteria (SRB). However, the biological role of FeS NPs in SRB remains understudied. Now, conductive FeS NPs function is demonstrated as an electron conduit enabling Desulfovibrio vulgaris Hildenborough, an SRB strain, to utilize solid‐state electron donors via direct electron uptake. After forming FeS NPs on the cell surface, D. vulgaris initiated current generation coupled with sulfate reduction on electrodes poised at −0.4 V versus standard hydrogen electrode. Single‐cell activity analysis showed that the electron uptake and metabolic rate via FeS NPs in D. vulgaris were about sevenfold higher than those via native cell‐surface proteins in other SRB. Leitfähige Eisensulfid‐Nanopartikel (FeS‐NPs) werden von sulfatreduzierenden Bakterien extrazellulär, intrazellulär und auf der Zelloberfläche synthetisiert. Diese FeS‐NPs ermöglichen Zellen die direkte Elektronenaufnahme von einer extrazellulären Elektrode gekoppelt mit einer metabolischen Energieproduktion. Die Ergebnisse geben Einblick in die physiologische und biogeochemische Rolle von natürlich vorkommenden FeS‐NPs.