EPR characterization of the new Qrc complex from sulfate reducing bacteria and its ability to form a supercomplex with hydrogenase and TpIc3

► Qrc is a membrane complex with Type I cytochrome c3:menaquinone reductase activity. ► We present an EPR characterization of the Qrc complex redox centers. ► Qrc forms a supercomplex with [NiFe] hydrogenase and Type I cytochrome c3.