TY - JOUR A1 - Kremp, Florian A1 - Roth, Jennifer A1 - Müller, Volker T1 - The Sporomusa type Nfn is a novel type of electron-bifurcating transhydrogenase that links the redox pools in acetogenic bacteria T2 - Scientific reports N2 - Flavin-based electron bifurcation is a long hidden mechanism of energetic coupling present mainly in anaerobic bacteria and archaea that suffer from energy limitations in their environment. Electron bifurcation saves precious cellular ATP and enables lithotrophic life of acetate-forming (acetogenic) bacteria that grow on H2 + CO2 by the only pathway that combines CO2 fixation with ATP synthesis, the Wood–Ljungdahl pathway. The energy barrier for the endergonic reduction of NADP+, an electron carrier in the Wood–Ljungdahl pathway, with NADH as reductant is overcome by an electron-bifurcating, ferredoxin-dependent transhydrogenase (Nfn) but many acetogens lack nfn genes. We have purified a ferredoxin-dependent NADH:NADP+ oxidoreductase from Sporomusa ovata, characterized the enzyme biochemically and identified the encoding genes. These studies led to the identification of a novel, Sporomusa type Nfn (Stn), built from existing modules of enzymes such as the soluble [Fe–Fe] hydrogenase, that is widespread in acetogens and other anaerobic bacteria. KW - Bacterial physiology KW - Metabolism KW - Oxidoreductases Y1 - 2020 UR - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/75721 UR - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-757211 SN - 2045-2322 N1 - This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 741791) and the German Research Foundation (DFG). Open access funding provided by Projekt DEAL. VL - 10 IS - art. 14872 SP - 1 EP - 14 PB - Macmillan Publishers Limited, part of Springer Nature CY - [London] ER -