title: X-ray structure of the gamma-subunit of a dissimilatory sulfite reductase: fixed and flexible C-terminal arms.
abstract: The X-ray structure of the gamma-subunit of the dissimilatory sulfite reductase (DsrC) from Archaeoglobus fulgidus was determined at 1.12 and 2.1A resolution, in the two crystal forms named DsrC(nat) and DsrC(ox) the latter being cocrystallized with the oxidizing agent tert-butyl hydroperoxide. The fold corresponds to that of the homologous protein from Pyrobaculum aerophilum but is significantly more compact. The most interesting, highly conserved C-terminal arm adopts a well-defined conformation in A. fulgidus DsrC in contrast to the completely disordered conformation in P. aerophilum DsrC. The functional relevance of both conformations and of a potentially redox-active disulfide bond between the strictly invariant Cys103 and Cys114 are discussed.
authors.affiliation: Max-Planck-Institut für terrestrische Mikrobiologie, Karl-von-Frisch-Str., D-35043 Marburg, Germany.
authors.forename: Gerd J
authors.initials: GJ
authors.lastname: Mander
authors.forename: Manfred S
authors.initials: MS
authors.lastname: Weiss
authors.forename: Reiner
authors.initials: R
authors.lastname: Hedderich
authors.forename: Jörg
authors.initials: J
authors.lastname: Kahnt
authors.forename: Ulrich
authors.initials: U
authors.lastname: Ermler
authors.forename: Eberhard
authors.initials: E
authors.lastname: Warkentin
mesh_terms: D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000737:chemistry* / Q000235:genetics; D019611:Archaeoglobus fulgidus / Q000201:enzymology*; D018360:Crystallography, X-Ray; D050885:Hydrogensulfite Reductase; D008958:Models, Molecular; D008969:Molecular Sequence Data; D050862:Oxidoreductases Acting on Sulfur Group Donors / Q000737:chemistry* / Q000235:genetics; D017434:Protein Structure, Tertiary; D021122:Protein Subunits / Q000737:chemistry*; D016415:Sequence Alignment
chemical_list: D019843:Archaeal Proteins; D021122:Protein Subunits; D050862:Oxidoreductases Acting on Sulfur Group Donors; D050885:Hydrogensulfite Reductase