Iron-sulfur clusters
Beinert, Holm and Münck reviewed iron-sulfur clusters, found in all life forms, which transfer electrons and also act as catalytic centres and as sensors of iron and oxygen.
As reported in: Beinert, Holm, Münck (1997). Iron-Sulfur Clusters: Nature's Modular, Multipurpose Structures. Science. doi:10.1126/science.277.5326.653
Abstract only