Identification of a Mo-Fe-S Cluster on NifEN by Mo K-Edge Extended X-ray Absorption Fine Structure

摘要

The iron-molybdenum cofactor (FeMo-co) is the complex metal-sulfur cofactor found within the active site of the molybdenum-iron protein (MoFe protein) component of the nitrogenase enzyme complex. FeMo-co is among the most complex metal-sulfur cofactors known in biology and is composed of 7 Fe, 9 S, Mo, X (C, N, or O) and R-homocitrate. This cofactor is required for the nitrogenase MoFe protein to catalyze the reduction of N_2 to NH_3 in nitrogen-fixing organisms, such as Azotobacter vinelandii or Rhodospirillum rubrum, and thus is essential for the input of nitrogen into the biosphere.