New iron-sulfur clusters help hydrogenases tolerate oxygen.
One S less: recent crystallographic studies have revealed a new, oxygen-tolerant kind of iron-sulfide cluster [4Fe-3S], which contains only three rather than four sulfur atoms in its cage (see picture; yellow=S, red=Fe, blue=N, green=cysteine). It is proposed that the cluster's ability to transfer multiple electrons increases the oxygen tolerance by enabling the enzyme to reduce O(2) rapidly, converting the dioxygen into harmless water before it can damage the protein.
Department of Chemistry, University of Rochester, NY 14627, USA.
Katarzyna
K
Grubel
Patrick L
PL
Holland
D018360:Crystallography, X-Ray; D006864:Hydrogenase / Q000737:chemistry* / Q000378:metabolism; D007501:Iron / Q000737:chemistry*; D008968:Molecular Conformation; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*; D017434:Protein Structure, Tertiary; D013455:Sulfur / Q000737:chemistry*
D013455:Sulfur; D007501:Iron; D006864:Hydrogenase; D010100:Oxygen