title: Bacterioferritin from Mycobacterium smegmatis contains zinc in its di-nuclear site.
abstract: Bacterioferritins, also known as cytochrome b (1), are oligomeric iron-storage proteins consisting of 24 identical amino acid chains, which form spherical particles consisting of 24 subunits and exhibiting 432 point-group symmetry. They contain one haem b molecule at the interface between two subunits and a di-nuclear metal binding center. The X-ray structure of bacterioferritin from Mycobacterium smegmatis (Ms-Bfr) was determined to a resolution of 2.7 A in the monoclinic space group C2. The asymmetric unit of the crystals contains 12 protein molecules: five dimers and two half-dimers located along the crystallographic twofold axis. Unexpectedly, the di-nuclear metal binding center contains zinc ions instead of the typically observed iron ions in other bacterioferritins.
authors.affiliation: EMBL Hamburg Outstation, D-22603 Hamburg, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Janowski
authors.forename: Tamar
authors.initials: T
authors.lastname: Auerbach-Nevo
authors.forename: Manfred S
authors.initials: MS
authors.lastname: Weiss
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D001665:Binding Sites; D018360:Crystallography, X-Ray; D003573:Cytochrome b Group / Q000737:chemistry* / Q000378:metabolism; D005293:Ferritins / Q000737:chemistry* / Q000378:metabolism; D006418:Heme / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D020102:Mycobacterium smegmatis / Q000737:chemistry*; D017386:Sequence Homology, Amino Acid; D013050:Spectrometry, Fluorescence; D015032:Zinc / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D003573:Cytochrome b Group; D006418:Heme; D005293:Ferritins; C018032:bacterioferritin; D015032:Zinc