A dissimilatory sirohaem-sulfite-reductase-type protein from the hyperthermophilic archaeon Pyrobaculum islandicum.
A sulfite-reductase-type protein was purified from the hyperthermophilic crenarchaeote Pyrobaculum islandicum grown chemoorganoheterotrophically with thiosulfate as terminal electron acceptor. In common with dissimilatory sulfite reductases the protein has an alpha 2 beta 2 structure and contains high-spin sirohaem, non-haem iron and acid-labile sulfide. The oxidized protein exhibits absorption maxima at 280, 392, 578 and 710 nm with shoulders at 430 and 610 nm. The isoelectric point of pH 8.4 sets the protein apart from all dissimilatory sulfite reductases characterized thus far. The genes for the alpha- and beta-subunits (dsrA and dsrB) are contiguous in the order dsrAdsrB and most probably comprise an operon with the directly following dsrG and dsrC genes. dsrG and dsrC encode products which are homologous to eukaryotic glutathione S-transferases and the proposed gamma-subunit of Desulfovibrio vulgaris sulfite reductase, respectively. dsrA and dsrB encode 44.2 kDa and 41.2 kDa peptides which show significant similarity to the two homologous subunits DsrA and DsrB of dissimilatory sulfite reductases. Phylogenetic analyses indicate a common protogenotic origin of the P. islandicum protein and the dissimilatory sulfite reductases from sulfate-reducing and sulfide-oxidizing prokaryotes. However, the protein from P. islandicum and the sulfite reductases from sulfate-reducers and from sulfur-oxidizers most probably evolved into three independent lineages prior to divergence of archaea and bacteria.
Molitor
Michael
M
Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany.
Dahl
Christiane
C
Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany.
Molitor
Ilka
I
Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany.
Schäfer
Ulrike
U
Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany.
Speich
Norbert
N
Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany.
Huber
Robert
R
Lehrstuhl für Mikrobiologie Universitätsstr. 31, 93053 Regensburg and Institut für Biochemie.
Deutzmann
Rainer
R
Universitätsstr. 31, 93053 Regensburg, Germany.
Trüper
Hans G
HG
Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany.
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics; D016969:Desulfovibrio vulgaris / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D005798:Genes, Bacterial; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism; D006418:Heme / Q000031:analogs & derivatives* / Q000378:metabolism; D007526:Isoelectric Point; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D009876:Operon; D010084:Oxidation-Reduction; D050862:Oxidoreductases Acting on Sulfur Group Donors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D010802:Phylogeny; D010957:Plasmids; D011487:Protein Conformation; D011995:Recombination, Genetic; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D019624:Thermoproteaceae / Q000201:enzymology* / Q000235:genetics* / Q000378:metabolism; D013885:Thiosulfates / Q000378:metabolism
D004269:DNA, Bacterial; D013885:Thiosulfates; D006418:Heme; C009272:siroheme; D050862:Oxidoreductases Acting on Sulfur Group Donors; D005982:Glutathione Transferase