Skip Header

You are using a version of Internet Explorer that may not display all features of this website. Please upgrade to a modern browser.
Contribute Send feedback
Read comments (?) or add your own

Q939U1 (SOXA_RHOSU) Reviewed, UniProtKB/Swiss-Prot

Last modified April 16, 2014. Version 52. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (2) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
SoxAX cytochrome complex subunit A

EC=1.8.2.-
Alternative name(s):
Cytochrome c551 subunit diheme
Protein SoxA
Sulfur oxidizing protein A
Thiosulfate-oxidizing multienzyme system protein SoxA
Short name=TOMES protein SoxA
Gene names
Name:soxA
OrganismRhodovulum sulfidophilum (Rhodobacter sulfidophilus)
Taxonomic identifier35806 [NCBI]
Taxonomic lineageBacteriaProteobacteriaAlphaproteobacteriaRhodobacteralesRhodobacteraceaeRhodovulum

Protein attributes

Sequence length287 AA.
Sequence statusComplete.
Sequence processingThe displayed sequence is further processed into a mature form.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

C-type diheme cytochrome, which is part of the SoxAX cytochrome complex involved in sulfur oxidation. The SoxAX complex catalyzes the formation of a heterodisulfide bond between the conserved cysteine residue on a sulfur carrier SoxYZ complex subunit SoxY and thiosulfate or other inorganic sulfur substrates. This leads to the liberation of two electrons, which may be transferred from the SoxAX complex to another cytochrome c and which then may be used for reductive CO2 fixation. Ref.1 Ref.2 Ref.3 Ref.4

Cofactor

Binds 2 heme groups per subunit. Ref.1 Ref.2 Ref.3 Ref.4

Subunit structure

Heterodimer of SoxA and SoxX. Ref.1 Ref.3 Ref.4

Subcellular location

Periplasm Ref.1.

Induction

By thiosulfate. Ref.1

Post-translational modification

Cysteine persulfide at Cys-248.

Disruption phenotype

Unable to grow photoautotrophically on or oxidize either thiosulfate or sulfide. Thiosulfate:cytochrome c oxidoreductase activity is zero in periplasmic extracts prepared from cells grown on thiosulfate plus malate. Ref.1

Sequence similarities

Belongs to the SoxA family.

Contains 1 cytochrome c domain.

Biophysicochemical properties

Redox potential:

E0 is approximately -340 mV for His/Cys- ligated heme (heme 1) and -400 mV for His/CysS- ligated heme (heme 2) at pH 7.0. Ref.4

Mass spectrometry

Molecular mass is 30177±4 Da from positions 27 - 287. Determined by ESI. The measured mass is that of mature SoxA with a diheme bound and with an undetermined modification. Ref.1

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Signal peptide1 – 2626 Ref.1
Chain27 – 287261SoxAX cytochrome complex subunit A
PRO_0000423489

Regions

Domain74 – 16895Cytochrome c

Sites

Active site2481Cysteine persulfide intermediate Ref.3 Ref.4
Metal binding1061Iron (heme 1 axial ligand); via tele nitrogen
Metal binding1401Iron (heme 1 axial ligand)
Metal binding2071Iron (heme 2 axial ligand); via tele nitrogen
Metal binding2481Iron (heme 2 axial ligand)
Binding site1021Heme 1 (covalent)
Binding site1051Heme 1 (covalent)
Binding site2031Heme 2 (covalent)
Binding site2061Heme 2 (covalent)
Binding site2441Substrate

Secondary structure

.......................................................... 287
Helix Strand Turn

Details...

Sequences

Sequence LengthMass (Da)Tools
Q939U1 [UniParc].

Last modified December 1, 2001. Version 1.
Checksum: 95748C569D40853F

FASTA28731,332
        10         20         30         40         50         60 
MKTMTGRLVA AALVCGGAFS GAAVSAGPDD PLVINGEIEI VTRAPTPAHL ADRFDEIRSG 

        70         80         90        100        110        120 
WTFRTDDTQA LEMDDFENSG MVFVEEARAV WDRPEGTEGK ACADCHGAVD DGMYGLRAVY 

       130        140        150        160        170        180 
PKYVESAGKV RTVEQMINAC RTSRMGAPEW DYIGPDMTAM VALIASVSRG MPVSVAIDGP 

       190        200        210        220        230        240 
AQSTWEKGRE IYYTRYGQLD LSCASCHEQY FDHYIRADHL SQGQINGFPS YRLKNARLNA 

       250        260        270        280 
VHDRFRGCIR DTRGVPFAVG SPEFVALELY VASRGNGLSV EGPSVRN 

« Hide

References

[1]"Cytochrome complex essential for photosynthetic oxidation of both thiosulfate and sulfide in Rhodovulum sulfidophilum."
Appia-Ayme C., Little P.J., Matsumoto Y., Leech A.P., Berks B.C.
J. Bacteriol. 183:6107-6118(2001) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], PROTEIN SEQUENCE OF 27-57; 66-73; 132-139; 255-266 AND 274-287, FUNCTION, CATALYTIC ACTIVITY, COFACTOR, SUBUNIT, SUBCELLULAR LOCATION, INDUCTION BY THIOSULFATE, MASS SPECTROMETRY, DISRUPTION PHENOTYPE, SIGNAL.
Strain: W4.
[2]"Novel heme ligation in a c-type cytochrome involved in thiosulfate oxidation: EPR and MCD of SoxAX from Rhodovulum sulfidophilum."
Cheesman M.R., Little P.J., Berks B.C.
Biochemistry 40:10562-10569(2001) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, COFACTOR, EPR SPECTROSCOPY OF THE HEMES, MAGNETIC CIRCULAR DICHROISM OF THE SOXAX COMPLEX.
Strain: W4.
[3]"Structural basis for the oxidation of thiosulfate by a sulfur cycle enzyme."
Bamford V.A., Bruno S., Rasmussen T., Appia-Ayme C., Cheesman M.R., Berks B.C., Hemmings A.M.
EMBO J. 21:5599-5610(2002) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (1.50 ANGSTROMS) OF 27-287 IN COMPLEXES WITH SOXX IN OXIDIZED AND REDUCED STATES AND HEMES, FUNCTION, COFACTOR, SUBUNIT, EPR SPECTROSCOPY OF THE HEMES, REACTION MECHANISM, ACTIVE SITE, CYSTEINE PERSULFIDE AT CYS-248.
Strain: W4.
[4]"Redox and chemical activities of the hemes in the sulfur oxidation pathway enzyme SoxAX."
Bradley J.M., Marritt S.J., Kihlken M.A., Haynes K., Hemmings A.M., Berks B.C., Cheesman M.R., Butt J.N.
J. Biol. Chem. 287:40350-40359(2012) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (2.35 ANGSTROMS) OF 27-287 IN COMPLEX WITH SOXX AND HEME, FUNCTION, COFACTOR, BIOPHYSICOCHEMICAL PROPERTIES, SUBUNIT, POTENTIOMETRIC TITRATION; EPR SPECTROSCOPY AND MAGNETIC CIRCULAR DICHROISM OF THE SOXAX COMPLEX, REACTION MECHANISM, ACTIVE SITE, CYSTEINE PERSULFIDE AT CYS-248.
Strain: W4.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
AY005800 Genomic DNA. Translation: AAF99434.1.

3D structure databases

PDBe
RCSB PDB
PDBj
EntryMethodResolution (Å)ChainPositionsPDBsum
1H31X-ray2.55A/C/E/G27-287[»]
1H32X-ray1.50A27-287[»]
1H33X-ray1.75A27-287[»]
2OZ1X-ray2.35A/C/E/G27-287[»]
ProteinModelPortalQ939U1.
SMRQ939U1. Positions 27-287.
ModBaseSearch...
MobiDBSearch...

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Family and domain databases

Gene3D1.10.760.10. 2 hits.
InterProIPR009056. Cyt_c-like_dom.
IPR025710. SoxA.
[Graphical view]
PIRSFPIRSF038455. SoxA. 1 hit.
SUPFAMSSF46626. SSF46626. 2 hits.
PROSITEPS51007. CYTC. 1 hit.
[Graphical view]
ProtoNetSearch...

Other

EvolutionaryTraceQ939U1.

Entry information

Entry nameSOXA_RHOSU
AccessionPrimary (citable) accession number: Q939U1
Entry history
Integrated into UniProtKB/Swiss-Prot: September 18, 2013
Last sequence update: December 1, 2001
Last modified: April 16, 2014
This is version 52 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programProkaryotic Protein Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families

PDB cross-references

Index of Protein Data Bank (PDB) cross-references