Inside view of a giant proton pump

Abstract

Inner workings: The X-ray crystal structure of the entire bacterial complex I at 3.3 Å resolution offers fascinating insights into a giant 536 kDa molecular machine. The respiratory chain complex seems to employ unique mechanisms of energetic coupling that are entirely different from those found in all other enzymes using redox energy to drive vectorial proton transport across a bioenergetic membrane.

Keywords: bioenergetics; complex I; proton pumps; structure elucidation; ubiquinone.