Fig. 3: Structure and activity of cleaved, dimeric Ycf1p.

a An atomic model of the Ycf1p dimer is shown with cylinders representing α-helices and arrows representing β-strands (centre). The protein domains are coloured as in Fig. 1. One of the protomers (on the right-hand side) is coloured in lighter shades to distinguish it from the other protomer (on the left-hand side). Bound lipids that could be modeled are shown in CPK colouring except with pink instead of grey for the hydrocarbon tails. Right, Protein interactions between protomers are shown. The protein backbone is represented by a schematic ribbon diagram and interacting residues are shown as sticks along with their cryo-EM densities. Left, Protein-lipid interactions that link the two protomers are shown. Cryo-EM densities for the lipids are shown in Supplementary Fig. 8. b The Ycf1p dimer is shown as viewed from the luminal side (right). Left, the density for additional hydrophobic molecules located at the TMD0/TMD0 interface between the two protomers is shown in purple. Cryo-EM densities for Ycf1p residues that interact with these molecules are shown in Supplementary Fig. Fig. 8. c Plots of the specific ATPase activity of monomeric and dimeric Ycf1p, without and with 100 μM GSSG. Bars represent the mean value with error bars showing the standard deviation derived from three independent measurements each from two separate preparations of cleaved Ycf1p.