1.14.99.67 Iron enzyme contains a nonheme dinuclear iron cluster, with 2.1 iron atoms per monomer. Addition of O2 to the diferrous state of the cluster results in an exceptionally long-lived intermediate (t1/2 is 3 h at 4°C) that is assigned as a peroxodiferric species. CmlI-peroxo does not have a my-eta1:eta1-peroxo ligand, a my-eta1:eta2-peroxo ligand is proposed 759395 1.14.99.67 Iron non-heme di-iron enzyme, iron content is 1.2-1.4 mol per mol of enzyme 760212