title: Ferrous iron- and sulfur-induced genes in Sulfolobus metallicus.
abstract: Genes of Sulfolobus metallicus that appeared to be upregulated in relation to growth on either ferrous iron or sulfur were identified using subtractive hybridization of cDNAs. The genes upregulated during growth on ferrous iron were found in a cluster, and most were predicted to encode membrane proteins. Quantitative reverse transcription-PCR of cDNA showed upregulation of most of these genes during growth on ferrous iron and pyrite compared to results during growth on sulfur. The highest expression levels observed included those for genes encoding proteins with similarities to cytochrome c oxidase subunits and a CbsA-like cytochrome. The genes identified here that may be involved in oxidation of ferrous iron by S. metallicus are termed fox genes. Of three available genomes of Sulfolobus species (S. tokodaii, S. acidocaldarius, and S. solfataricus), only that of S. tokodaii has a cluster of highly similar open reading frames, and only S. tokodaii of these three species was also able to oxidize ferrous iron. A gene encoding sulfur oxygenase-reductase was identified as the source of the dominant transcript in sulfur-grown cells of S. metallicus, with the predicted protein showing high identities to the previously described examples from S. tokodaii and species of Acidianus.
authors.affiliation: Department of Biological Sciences, University of Warwick, Coventry, UK.
authors.forename: Stephan
authors.initials: S
authors.lastname: Bathe
authors.forename: Paul R
authors.initials: PR
authors.lastname: Norris
mesh_terms: D003580:Cytochromes / Q000235:genetics; D019641:DNA, Archaeal / Q000737:chemistry / Q000235:genetics; D003576:Electron Transport Complex IV / Q000235:genetics; D005296:Ferrous Compounds / Q000378:metabolism; D019848:Gene Expression Regulation, Archaeal; D015723:Gene Library; D019766:Genes, Archaeal; D007501:Iron / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D005810:Multigene Family; D009693:Nucleic Acid Hybridization; D016366:Open Reading Frames; D010084:Oxidation-Reduction; D050862:Oxidoreductases Acting on Sulfur Group Donors / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D013440:Sulfides / Q000378:metabolism; D016944:Sulfolobus / Q000201:enzymology* / Q000235:genetics* / Q000378:metabolism; D013455:Sulfur / Q000378:metabolism*
chemical_list: D003580:Cytochromes; D019641:DNA, Archaeal; D005296:Ferrous Compounds; D008565:Membrane Proteins; D013440:Sulfides; C011342:pyrite; D013455:Sulfur; D007501:Iron; D050862:Oxidoreductases Acting on Sulfur Group Donors; D003576:Electron Transport Complex IV