title: Structural and phylogenetic analysis of Rhodobacter capsulatus NifF: uncovering general features of nitrogen-fixation (nif)-flavodoxins.
abstract: Analysis of the crystal structure of NifF from Rhodobacter capsulatus and its homologues reported so far reflects the existence of unique structural features in nif flavodoxins: a leucine at the re face of the isoalloxazine, an eight-residue insertion at the C-terminus of the 50's loop and a remarkable difference in the electrostatic potential surface with respect to non-nif flavodoxins. A phylogenetic study on 64 sequences from 52 bacterial species revealed four clusters, including different functional prototypes, correlating the previously defined as "short-chain" with the firmicutes flavodoxins and the "long-chain" with gram-negative species. The comparison of Rhodobacter NifF structure with other bacterial flavodoxin prototypes discloses the concurrence of specific features of these functional electron donors to nitrogenase.
authors.affiliation: Department of Crystallography and Structural Biology, Institute of Physical-Chemistry "Rocasolano", CSIC, Serrano 119, Madrid 28006, Spain. xjuan@iqfr.csic.es.
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Pérez-Dorado
authors.forename: Ana
authors.initials: A
authors.lastname: Bortolotti
authors.forename: Néstor
authors.initials: N
authors.lastname: Cortez
authors.forename: Juan A
authors.initials: JA
authors.lastname: Hermoso
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites / Q000235:genetics; D018360:Crystallography, X-Ray; D005486:Flavin Mononucleotide / Q000737:chemistry; D005418:Flavodoxin / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D005798:Genes, Bacterial / Q000235:genetics*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009586:Nitrogen Fixation / Q000235:genetics*; D010802:Phylogeny; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D016354:Rhodobacter capsulatus / Q000235:genetics* / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D055672:Static Electricity
chemical_list: D005418:Flavodoxin; D005486:Flavin Mononucleotide