Cofactor FeMco (M = Mo, V, Fe) in nitrogenase

Abstract

Nitrogen fixation is a process widely investigated due to its great relevance to several fields, especially in agriculture. Nitrogen fixation is the process, which, as a component of the biogeochemical nitrogen cycle, drives the conversion of atmospheric N2 into ammonium ions. The enzyme nitrogenase has been studied with the purpose of developing systems capable of emulating (mimicking) it. It has been shown that it is a metallo-enzyme with a cofactor, constituted by two different metallo-clusters, one iron-sulfur and the other an iron-metal cluster, where the second metal atom may be molybdenum, vanadium or iron itself. Several reaction mechanisms have been formulated based upon structural, theoretical and experimental evidence, but the comprehension of the whole process is quite far from being fulfilled.