Nitrogenase FeMoco investigated by spatially resolved anomalous dispersion refinement

Abstract: The [Mo:7Fe:9S:C] iron-molybdenum cofactor (FeMoco) of nitrogenase is the largest known metal cluster and catalyses the 6-electron reduction of dinitrogen to ammonium in biological nitrogen fixation. Only recently its atomic structure was clarified, while its reactivity and electronic structure remain under debate. Here we show that for its resting S=3/2 state the common iron oxidation state assignments must be reconsidered. By a spatially resolved refinement of the anomalous scattering contributions of the 7 Fe atoms of FeMoco, we conclude that three irons (Fe1/3/7) are more reduced than the other four (Fe2/4/5/6). Our data are in agreement with the recently revised oxidation state assignment for the molybdenum ion, providing the first spatially resolved picture of the resting-state electron distribution within FeMoco. This might provide the long-sought experimental basis for a generally accepted theoretical description of the cluster that is in line with available spectroscopic and functional data

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch
• Notes: Nature communications. 7 (2016), article no. 10902, DOI 10.1038/ncomms10902, issn: 2041-1723

Classification and Topics

• Keyword: Nitrogenase ; Anomale Dispersion ; Biogeochemie ; Metalloproteinasen ; Oxidoreductasen ; Strukturbiologie

Contributors, Places and Time

• Event: Veröffentlichung
• (where): Freiburg
• (who): Universität
• (when): 2018
• Creator: Spatzal, Thomas ; Netzer, Julia Clarissa ; Burger, Eva-Maria Michaela ; Sippel, Daniel ; Zhang, Limei ; Andrade, Susana ; Rees, Douglas C. ; Einsle, Oliver
• Contributor: Albert-Ludwigs-Universität Freiburg. Institut für Biochemie ; Albert-Ludwigs-Universität Freiburg. Centre for Biological Signalling Studies ; Albert-Ludwigs-Universität Freiburg

Further information

• DOI: 10.1038/ncomms10902
• URN: urn:nbn:de:bsz:25-freidok-150424
• Rights: Kein Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 14.08.2025, 10:49 AM CEST