Abstract

Complex I Under Scrutiny Mitochondrial complex I is a large macromolecular membrane complex that couples electron transfer to proton pumping across the mitochondrial membrane and helps to drive adenosine 5′-triphosphate synthesis. Hunte et al. (p. 448 , published online 1 July) now describe the structure of complex 1 from the aerobic yeast, Yarrowia lipolytica . The sites involved in redox chemistry are distant from those that pump protons, and the structure suggests that a 60-angstrom-long helix is involved in transducing energy to the proton-pumping elements.