Contents

25 August 1995
Vol 269, Issue 5227

About The Cover

Crystal structure showing active site of oxidized bovine heart cytochrome c oxidase at a resolution of 2.8 angstroms. A heme (pink and red) with a copper atom (light blue) nearby is the oxygen binding and reduction site to which electrons are supplied from the other heme and a dinuclear copper center, located 12 and 22 angstroms away, respectively. A magnesium atom (yellow) with a water oxygen (orange) is at the interface between subunits I (green) and II (white). See page 1069 and the related Perspective on page 1063.