Catalysis of an Oxidation Reduction (redox) Reaction a Reversible Chemical Reaction in Which the Oxidation State of an Atom or Atoms Within a Molecule Is Altered. One Substrate Acts As a Hydrogen or Electron Donor and Becomes Oxidized While the Other Acts As Hydrogen or Electron Acceptor and Becomes Reduced.
Interacting Selectively and Non Covalently with a 4 Iron 4 Sulfur (4fe 4s) Cluster; This Cluster Consists of Four Iron Atoms with the Inorganic Sulfur Atoms Found Between the Irons and Acting As Bridging Ligands.
Any Molecular Entity That Serves As an Electron Acceptor and Electron Donor in an Electron Transport Chain. an Electron Transport Chain Is a Process in Which a Series of Electron Carriers Operate Together to Transfer Electrons From Donors to Any of Several Different Terminal Electron Acceptors to Generate a Transmembrane Electrochemical Gradient.