Nitrogenase biological nitrogen fixation

Non-enzvmatic simulation of nitrogenase reactions and the mechanism of biological nitrogen fixation. G. N. Schrauzer, Angew. Chem., Int. Ed. Engl., 1975, 14, 514-522 (36). 

The biological nitrogen fixation process is Introduced. Discussion focusses on the Dominant Hypothesis of nitrogenase composition and functioning. The enzyme system catalyzes the six-electron reduction of N2 to 2 NH3 concomitant with the evolution of H2. ATP hydrolysis drives the process. The two protein components of the enzyme,... 

The electrosynthesis of hydride complexes directly from molecular hydrogen at atmospheric pressure by reduction of Mo(II) and W(II) tertiary phosphine precursors in moderate yield has been described as also the electrosynthesis of trihydride complexes of these metals by reduction of M(IV) dihydride precursors [101,102]. Hydrogen evolution at the active site of molybdenum nitrogenases [103] is intimately linked with biological nitrogen fixation and the electrochemistry of certain well-defined mononuclear molybdenum and tungsten hydrido species has been discussed in this context [104,105]. 

The studies discussed so far deal - for good reasons - with the isolated FeMoco. However, qualitative molecular modeling has also been used to identify possible proton transfer routes from the surface of the nitrogenase protein to the FeMoco (40) and mechanistic aspects of biological nitrogen fixation are discussed in the light of such data (10-12). 

Syrtsova, L. A., Druzhinin, S.Y., Rubtsova, E.T., Shkondina, N.I. (1998), New possibilities for studying mechanism of nitrogenase reaction with photodonors of electron, Curr. Plant Sci. Biotechnol Agric. 31 (Biological Nitrogen Fixation for the 21st Century), 49-50. 

W. E. Newton, Isolated iron-molybdenum cofactor of nitrogenase, in Biological Nitrogen Fixation , eds. G. Stacey, R. H. Burris, and H. J. Evan, Chapman HaU, New York, 1992, p. 877. 

J. Kim and D.C. Rees. 1989. Nitrogenase and biological nitrogen fixation Biochemistry 33 389-397. (PubMed)... 

Biological nitrogen fixation is accomplished through the catalytic action of an enzyme known as nitrogenase. Nitrogenase consists of two distinct proteins which contain molybdenum, iron, and sulfur. Because the nitrogenase proteins are denatured by exposure to... 

On chemical grounds, Williams and Wentworth (3) proposed that the reduction of N2 to NH3 at a transition metal site involving Mo could equally well occur at a site containing V. However, in the context of biological nitrogen fixation, the unequivocal demonstration that V could participate in this process was a surprising development (4), as was the subsequent description in 1988 of a nitrogenase that contains Fe and appears to involve neither Mo nor V (5). 

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