title: Solution structure of Pyrobaculum aerophilum DsrC, an archaeal homologue of the gamma subunit of dissimilatory sulfite reductase.
abstract: The solution structure of DsrC, an archaeal homologue of the gamma subunit of dissimilatory sulfite reductase, has been determined by NMR spectroscopy. This 12.7-kDa protein from the hyperthermophilic archaeon Pyrobaculum aerophilum adopts a novel fold consisting of an orthogonal helical bundle with a beta hairpin along one side. A portion of the structure resembles the helix-turn-helix DNA-binding motif common in transcriptional regulator proteins. The protein contains two disulfide bonds but remains folded following reduction of the disulfides. DsrC proteins from organisms other than Pyrobaculum species do not contain these disulfide bonds. A conserved cysteine next to the C-terminus, which is not involved in the disulfide bonds, is located on a seven-residue C-terminal arm that is not part of the globular protein and is likely to dynamically sample more than one conformation.
authors.affiliation: Pacific Northwest National Laboratory, Environmental Molecular Sciences Laboratory, Richland, Washington, USA.
authors.forename: J R
authors.initials: JR
authors.lastname: Cort
authors.forename: S V
authors.initials: SV
authors.lastname: Mariappan
authors.forename: C Y
authors.initials: CY
authors.lastname: Kim
authors.forename: M S
authors.initials: MS
authors.lastname: Park
authors.forename: T S
authors.initials: TS
authors.lastname: Peat
authors.forename: G S
authors.initials: GS
authors.lastname: Waldo
authors.forename: T C
authors.initials: TC
authors.lastname: Terwilliger
authors.forename: M A
authors.initials: MA
authors.lastname: Kennedy
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D017931:DNA Primers; D050885:Hydrogensulfite Reductase; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D050862:Oxidoreductases Acting on Sulfur Group Donors / Q000737:chemistry*; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry; D017386:Sequence Homology, Amino Acid; D019624:Thermoproteaceae / Q000201:enzymology*
chemical_list: D017931:DNA Primers; D011994:Recombinant Proteins; D050862:Oxidoreductases Acting on Sulfur Group Donors; D050885:Hydrogensulfite Reductase