Sirohaem sulfite reductase and other proteins encoded by genes at the dsr locus of Chromatium vinosum are involved in the oxidation of intracellular sulfur

Pott, Andrea S.; Dahl, Christiane

doi:10.1099/00221287-144-7-1881

Cited by 194 publications

(220 citation statements)

References 52 publications

Supporting

Mentioning

210

Contrasting

Order By: Relevance

“…One gene (Peg.0221) encodes a protein with considerable similarity to sulfide:quinone oxidoreductase (sqr), which could catalyze the oxidation of sulfide (S 2 À ) to elemental sulfur (S 0 ) (Pott and Dahl, 1998;Reinartz et al, 1998). Elemental sulfur could be further oxidized to sulfite by the dissimilatory sulfite reductase encoded by dsrABDEFH genes that have been found in the sequenced genome (Dahl et al, 2005;Holkenbrink et al, 2011).…”

Section: Sulfur Metabolismmentioning

confidence: 99%

Genomic insights into the uncultured genus ‘Candidatus Magnetobacterium’ in the phylum Nitrospirae

et al. 2014

View full text Add to dashboard Cite

Magnetotactic bacteria (MTB) of the genus 'Candidatus Magnetobacterium' in phylum Nitrospirae are of great interest because of the formation of hundreds of bullet-shaped magnetite magnetosomes in multiple bundles of chains per cell. These bacteria are worldwide distributed in aquatic environments and have important roles in the biogeochemical cycles of iron and sulfur. However, except for a few short genomic fragments, no genome data are available for this ecologically important genus, and little is known about their metabolic capacity owing to the lack of pure cultures. Here we report the first draft genome sequence of 3.42 Mb from an uncultivated strain tentatively named 'Ca. Magnetobacterium casensis' isolated from Lake Miyun, China. The genome sequence indicates an autotrophic lifestyle using the Wood-Ljungdahl pathway for CO 2 fixation, which has not been described in any previously known MTB or Nitrospirae organisms. Pathways involved in the denitrification, sulfur oxidation and sulfate reduction have been predicted, indicating its considerable capacity for adaptation to variable geochemical conditions and roles in local biogeochemical cycles. Moreover, we have identified a complete magnetosome gene island containing mam, mad and a set of novel genes (named as man genes) putatively responsible for the formation of bullet-shaped magnetite magnetosomes and the arrangement of multiple magnetosome chains. This first comprehensive genomic analysis sheds light on the physiology, ecology and biomineralization of the poorly understood 'Ca. Magnetobacterium' genus.

show abstract

Section: Sulfur Metabolismmentioning

confidence: 99%

Genomic insights into the uncultured genus ‘Candidatus Magnetobacterium’ in the phylum Nitrospirae

et al. 2014

View full text Add to dashboard Cite

show abstract

“…This is evidenced by the presence of signal peptide-encoding sequences in the genes for the three structural proteins constituting the sulfur globule envelope (Pattaragulwanit et al, 1998;Prange et al, 2004;Frigaard & Dahl, 2008). For further oxidation of stored sulfur, the so-called Dsr system is of essential importance (Pott & Dahl, 1998;Dahl et al, 2005;Lübbe et al, 2006;Sander et al, 2006). The product of the Dsr pathway is sulfite, generated by a reverse-acting dissimilatory sulfite reductase (DsrAB), an enzyme that is well known to be located in the cytoplasm (Hipp et al, 1997;Pott & Dahl, 1998;Frigaard & Dahl, 2008).…”

Section: Introductionmentioning

confidence: 99%

“…For further oxidation of stored sulfur, the so-called Dsr system is of essential importance (Pott & Dahl, 1998;Dahl et al, 2005;Lübbe et al, 2006;Sander et al, 2006). The product of the Dsr pathway is sulfite, generated by a reverse-acting dissimilatory sulfite reductase (DsrAB), an enzyme that is well known to be located in the cytoplasm (Hipp et al, 1997;Pott & Dahl, 1998;Frigaard & Dahl, 2008).…”

Section: Introductionmentioning

confidence: 99%

“…The first major process in the oxidation of thiosulfate and sulfide is the formation of intracellularly stored sulfur globules. The oxidation of thiosulfate to sulfate with sulfur globules as an intermediate involves the periplasmic Sox proteins SoxYZ, SoxB, SoxXAK and SoxL (Pott & Dahl, 1998;Hensen et al, 2006;Welte et al, 2009). For the oxidation of sulfide, A. vinosum possesses the genetic equipment for at least three different enzymes catalysing this reaction, namely the soluble periplasmic flavocytochrome c and the membrane-bound sulfide : quinone oxidoreductases SqrD and SqrF.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Sulfite oxidation in the purple sulfur bacterium Allochromatium vinosum: identification of SoeABC as a major player and relevance of SoxYZ in the process

et al. 2013

Self Cite

View full text Add to dashboard Cite

In phototrophic sulfur bacteria, sulfite is a well-established intermediate during reduced sulfur compound oxidation. Sulfite is generated in the cytoplasm by the reverse-acting dissimilatory sulfite reductase DsrAB. Many purple sulfur bacteria can even use externally available sulfite as a photosynthetic electron donor. Nevertheless, the exact mode of sulfite oxidation in these organisms is a long-standing enigma. Indirect oxidation in the cytoplasm via adenosine-59-phosphosulfate (APS) catalysed by APS reductase and ATP sulfurylase is neither generally present nor essential. The inhibition of sulfite oxidation by tungstate in the model organism Allochromatium vinosum indicated the involvement of a molybdoenzyme, but homologues of the periplasmic molybdopterin-containing SorAB or SorT sulfite dehydrogenases are not encoded in genome-sequenced purple or green sulfur bacteria. However, genes for a membrane-bound polysulfide reductase-like iron-sulfur molybdoprotein (SoeABC) are universally present. The catalytic subunit of the protein is predicted to be oriented towards the cytoplasm. We compared the sulfide-and sulfite-oxidizing capabilities of A. vinosum WT with single mutants deficient in SoeABC or APS reductase and the respective double mutant, and were thus able to prove that SoeABC is the major sulfite-oxidizing enzyme in A. vinosum and probably also in other phototrophic sulfur bacteria. The genes also occur in a large number of chemotrophs, indicating a general importance of SoeABC for sulfite oxidation in the cytoplasm. Furthermore, we showed that the periplasmic sulfur substrate-binding protein SoxYZ is needed in parallel to the cytoplasmic enzymes for effective sulfite oxidation in A. vinosum and provided a model for the interplay between these systems despite their localization in different cellular compartments.

show abstract

“…MC-1) contain a putative sulfur transferase complex (DsrEFH) and an ironsulfur flavoprotein with NADH oxidoreductase activity (DsrL). Individual gene inactivation of dsrA, dsrB, dsrH, dsrM, dsrK, dsrL, dsrJ, dsrO and dsrP completely prevents oxidation of sulfur globules in A. vinosum, whereas individual gene inactivation of dsrN and dsrR significantly reduces the oxidation rate of sulfur globules (Dahl et al, 2005;Grimm et al, 2010;Lübbe et al, 2006;Pott & Dahl, 1998;Sander et al, 2006).…”

Section: Introductionmentioning

confidence: 99%

Sulfur globule oxidation in green sulfur bacteria is dependent on the dissimilatory sulfite reductase system

et al. 2011

View full text Add to dashboard Cite

Green sulfur bacteria (GSB) oxidize sulfide and thiosulfate to sulfate, with extracellular globules of elemental sulfur as an intermediate. Here we investigated which genes are involved in the formation and consumption of these sulfur globules in the green sulfur bacterium Chlorobaculum tepidum. We show that sulfur globule oxidation is strictly dependent on the dissimilatory sulfite reductase (DSR) system. Deletion of dsrM/CT2244 or dsrT/CT2245, or the two dsrCABL clusters (CT0851-CT0854, CT2247-2250), abolished sulfur globule oxidation and prevented formation of sulfate from sulfide, whereas deletion of dsrU/CT2246 had no effect. The DSR system also seems to be involved in the formation of thiosulfate, because thiosulfate was released from wild-type cells during sulfide oxidation, but not from the dsr mutants. The dsr mutants incapable of complete substrate oxidation oxidized sulfide and thiosulfate about twice as fast as the wild-type, while having only slightly lower growth rates (70-80 % of wild-type). The increased oxidation rates seem to compensate for the incomplete substrate oxidation to satisfy the requirement for reducing equivalents during growth. A mutant in which two sulfide : quinone oxidoreductases (sqrD/CT0117 and sqrF/CT1087) were deleted exhibited a decreased sulfide oxidation rate (~50 % of wild-type), yet formation and consumption of sulfur globules were not affected. The observation that mutants lacking the DSR system maintain efficient growth suggests that the DSR system is dispensable in environments with sufficiently high sulfide concentrations. Thus, the DSR system in GSB may have been acquired by horizontal gene transfer as a response to a need for enhanced substrate utilization in sulfide-limiting habitats.

show abstract

Sirohaem sulfite reductase and other proteins encoded by genes at the dsr locus of Chromatium vinosum are involved in the oxidation of intracellular sulfur

Cited by 194 publications

References 52 publications

Genomic insights into the uncultured genus ‘Candidatus Magnetobacterium’ in the phylum Nitrospirae

Genomic insights into the uncultured genus ‘Candidatus Magnetobacterium’ in the phylum Nitrospirae

Sulfite oxidation in the purple sulfur bacterium Allochromatium vinosum: identification of SoeABC as a major player and relevance of SoxYZ in the process

Sulfur globule oxidation in green sulfur bacteria is dependent on the dissimilatory sulfite reductase system

Contact Info

Product

Resources

About