The heme-copper oxidase superfamily shares a Zn2+-binding motif at the entrance to a proton pathway

• Heme-copper oxidases (HCuOs) catalyse the reduction of oxygen, using the liberated free energy to maintain a proton-motive force across the membrane. In the mitochondrial-like A-type HCuOs, binding of heavy metal ions at the surface of the protein inhibits proton transfer. In bacterial C-type oxidases, the entry point to the proton pathway is on an accessory subunit unrelated to any subunit in A-type HCuOs. Despite this, we show here that heavy metal ions such as Zn2+ inhibit O-2-reduction very similarly in C-type as in A-type HCuOs, and furthermore that the binding site shares the same Glu-His motif. (C) 2013 Federation of European Biochemical Societies.

Subject headings

NATURVETENSKAP  -- Biologi -- Biokemi och molekylärbiologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Biochemistry and Molecular Biology (hsv//eng)

Keyword

cbb(3)

Proton transfer

K-pathway

Nickel

Liposome

Nitric oxide reductase

Publication and Content Type

ref (subject category)

art (subject category)