Structural basis of biological nitrogen fixation
Philosophical Transactions of the Royal Society A Mathematical Physical and Engineering SciencesPublished 5 April 2005
Douglas C. Rees, F. Akif Tezcan, Chad Haynes, Mika Y. Walton, Susana L. A. Andrade, Oliver Einsle
Citations1,117
SJR quartileQ1
SJR score1.03
SNIP1.59
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TL;DR
An overview of the nitrogenase system is presented that emphasizes the structural organization of the proteins and associated metalloclusters that have the remarkable ability to catalyse nitrogen fixation under ambient conditions.
Abstract
Biological nitrogen fixation is mediated by the nitrogenase enzyme system that catalyses the ATP dependent reduction of atmospheric dinitrogen to ammonia. Nitrogenase consists of two component metalloproteins, the MoFe-protein with the FeMo-cofactor that provides the active site for substrate reduction, and the Fe-protein that couples ATP hydrolysis to electron transfer. An overview of the nitrogenase system is presented that emphasizes the structural organization of the proteins and associated metalloclusters that have the remarkable ability to catalyse nitrogen fixation under ambient conditions. Although the mechanism of ammonia formation by nitrogenase remains enigmatic, mechanistic inferences motivated by recent developments in the areas of nitrogenase biochemistry, spectroscopy, model chemistry and computational studies are discussed within this structural framework.
Keywords
EnergyChemical Engineering
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100 Citations2004Uwe Huniar, Reinhart Ahlrichs +1 more
The proposed mechanism explores the possibilities that redox-induced distortions facilitate insertion of N(2) and derivative substrates into the Fe(6) central unit of the cofactor, (b) the central atom in the co Factor is an exchangeable nitrogen, and (c) the individual steps are related by H(+)/e(-) additions (and reduction of substrate) or aquation/dehydration (and distortion of the Fe (6) center).
BiochemistrySubstrate reduction properties of dinitrogenase activated in vitro are dependent upon the presence of homocitrate or its analogs during iron-molybdenum cofactor synthesis
99 Citations1989Juan Imperial, Timothy R. Hoover +3 more
The structural features of the homocitrate molecule absolutely required for the synthesis of a catalytically competent iron-molybdenum cofactor were determined to be the hydroxyl group, the 1- and 2-carboxyl groups, and the R configuration of the chiral center.
Journal of Biological ChemistryIncorporation of Iron and Sulfur from NifB Cofactor into the Iron-Molybdenum Cofactor of Dinitrogenase
97 Citations1995Ronda M. Allen, Ranjini Chatterjee +2 more
The data clearly demonstrate that iron and sulfur from active NifB-co are specifically incorporated into FeMo-co of dinitrogenase and provide direct biochemical identification of an iron-sulfur precursor of Fe Mo-co.
BiochemistryXenon and Halogenated Alkanes Track Putative Substrate Binding Cavities in the Soluble Methane Monooxygenase Hydroxylase<sup>,</sup>
96 Citations2001Douglas A. Whittington, Amy C. Rosenzweig +2 more
Results indicate that hydrophobic species bind preferentially in preexisting cavities in MMOH and support the hypothesis that such cavities may play a functional role in sequestering and enhancing the availability of the physiological substrates for reaction at the active site.
BiochemistryBiochemical and Structural Characterization of the Cross-Linked Complex of Nitrogenase: Comparison to the ADP-AlF<sub>4</sub><sup>-</sup>-Stabilized Structure<sup>,</sup>
96 Citations2002Benedikt Schmid, Oliver Einsle +5 more
The results of these studies suggest that EDC cross-linking traps a nucleotide-independent precomplex of the nitrogenase proteins driven by complementary electrostatic interactions that subsequently rearranges in aucleotide-dependent fashion to the electron transfer competent state observed in the ADP-AlF(4)(-) structure.
FEBS LettersA novel S = 3/2 EPR signal associated with native Fe‐proteins of nitrogenase
96 Citations1985Wilfred R. Hagen, Robert R. Eady +2 more
In addition to their g = 1.94 EPR signal, nitrogenase Fe‐proteins from Azotobacter vinelandii, AzotOBacter chroococcum and Klebsiella pneumoniae exhibit a weak EPR Signal with g ≅5.4.
Journal of the American Chemical SocietyThe Interstitial Atom of the Nitrogenase FeMo-Cofactor: ENDOR and ESEEM Show It Is Not an Exchangeable Nitrogen
95 Citations2003Hong-In Lee, Paul M. C. Benton +5 more
None of the ENDOR and ESEEM signals vanish or are altered by catalytic turnover with 15N2, and no new 15N signal is detected, leading to the conclusion that if species X is a nitrogen atom, it does not exchange during dinitrogen reduction.
Journal of Biological ChemistryCharacteristics of NIFNE in Azotobacter vinelandii Strains
93 Citations1995Jon T. Roll, Vinod K. Shah +2 more
A model where both NifB-co and dinitrogenase reductase participate in FeMo-co synthesis through NIFNE, which serves as a scaffold for this process is supported.
Journal of Biological ChemistryInvolvement of the P Cluster in Intramolecular Electron Transfer within the Nitrogenase MoFe Protein
91 Citations1995John W. Peters, Karl Fisher +2 more
BiochemistryMgATP-Bound and Nucleotide-Free Structures of a Nitrogenase Protein Complex between the Leu 127Δ-Fe-Protein and the MoFe-Protein<sup>,</sup>
90 Citations2000Hsiu‐Ju Chiu, John W. Peters +5 more
The L127Delta mutation precludes key interactions between the Fe-protein and nucleotide, especially, but not exclusively, in the region corresponding to the switch II region of G-proteins, where the deletion constrains Gly 128 and Asp 129 from forming hydrogen bonds to the gamma-phosphate and activating water for attack on this group, respectively.
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