Fig. 1: Overall architecture of the SDH from S. cerevisiae.

a Cryo-EM map of SDH at 3.36 Å resolution and cartoon representation of ScSDH. The SDH protein has a total length of 108 Å and a transmembrane portion of 40 Å. SDHA, SDHB, SDHC, and SDHD subunits are colored in blue, orange, green, and yellow individually. b Cartoon representation of SDHA subunits. FAD is shown as stick. All domains are color-coded. c Cartoon representation of SDHB subunits. FeS clusters are shown as spheres. All domains are color-coded. d Cartoon representation of hydrophobic transmembrane subunits SDHC and SDHD in front view and top view. The six transmembrane helices are labeled. PE phosphatidylethanolamine (shown as gray stick).