Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published July 26, 1993 | public
Book Section - Chapter

Crystal Structures of the Iron Protein and Molybdenum-Iron Protein of Nitrogenase


Three-dimensional structures of the nitrogenase iron protein and molybdenum-iron protein from Azotobacter vinelandii have been determined by x-ray crystallography. The iron protein contains a single 4Fe:4S cluster symmetrically liganded by two identical subunits. The molybdenum-iron protein is an α_2β_2 tetramer, where the homologous α and β subunits surround two different types of metal centers: the FeMo-cofactor and the P-cluster pair. Both centers are constructed from two bridged clusters; the FeMo-cofactor has 4Fe:3S and 1Mo:3Fe:3S cluster bridged by three non-protein ligands, while the P-cluster pair contains two 4Fe:4S clusters bridged by two cysteine ligands located at the αβ subunit interface. Docking studies between the iron protein and molybdenum iron protein suggest a possible interaction mode between these two proteins.

Additional Information

© 1993 American Chemical Society. Received March 8, 1993. Published in print 26 July 1993. Stimulating discussions with J.B. Howard, J.E. Bercaw and H.B. Gray are gready appreciated. This work was supported by NSF DMB91-18689 and NIH GM45162. The rotation camera facility at the Stanford Synchrotron Radiation Laboratory is supported by the DOE Office of Basic Energy Sciences and the NIH Biomedical Resource Technology Program, Division of Research Resources. X-PLOR calculations wre performed on the CRAY-YMP at the San Diego Supercomputer Center, supported by NSF.

Additional details

August 20, 2023
January 14, 2024