SOXA_CHLTE
ID SOXA_CHLTE Reviewed; 286 AA.
AC Q8KDM7;
DT 18-SEP-2013, integrated into UniProtKB/Swiss-Prot.
DT 01-OCT-2002, sequence version 1.
DT 03-AUG-2022, entry version 100.
DE RecName: Full=L-cysteine S-thiosulfotransferase subunit SoxA {ECO:0000305};
DE EC=2.8.5.2 {ECO:0000269|PubMed:18641134};
DE AltName: Full=Cytochrome c551 subunit monoheme {ECO:0000303|PubMed:18641134};
DE AltName: Full=Protein SoxA {ECO:0000250|UniProtKB:Q8RLX0};
DE AltName: Full=SoxAX cytochrome complex subunit A {ECO:0000250|UniProtKB:Q8RLX0};
DE AltName: Full=Sulfur oxidizing protein A {ECO:0000312|EMBL:AAM72253.1};
DE AltName: Full=Thiosulfate-oxidizing multienzyme system protein SoxA {ECO:0000250|UniProtKB:D7A6E5};
DE Short=TOMES protein SoxA {ECO:0000250|UniProtKB:D7A6E5};
DE Flags: Precursor;
GN Name=soxA {ECO:0000312|EMBL:AAM72253.1}; OrderedLocusNames=CT1019;
OS Chlorobaculum tepidum (strain ATCC 49652 / DSM 12025 / NBRC 103806 / TLS)
OS (Chlorobium tepidum).
OC Bacteria; Chlorobi; Chlorobia; Chlorobiales; Chlorobiaceae; Chlorobaculum.
OX NCBI_TaxID=194439;
RN [1] {ECO:0000312|EMBL:AAM72253.1}
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=ATCC 49652 / DSM 12025 / NBRC 103806 / TLS;
RX PubMed=12093901; DOI=10.1073/pnas.132181499;
RA Eisen J.A., Nelson K.E., Paulsen I.T., Heidelberg J.F., Wu M., Dodson R.J.,
RA DeBoy R.T., Gwinn M.L., Nelson W.C., Haft D.H., Hickey E.K., Peterson J.D.,
RA Durkin A.S., Kolonay J.F., Yang F., Holt I.E., Umayam L.A., Mason T.M.,
RA Brenner M., Shea T.P., Parksey D.S., Nierman W.C., Feldblyum T.V.,
RA Hansen C.L., Craven M.B., Radune D., Vamathevan J.J., Khouri H.M.,
RA White O., Gruber T.M., Ketchum K.A., Venter J.C., Tettelin H., Bryant D.A.,
RA Fraser C.M.;
RT "The complete genome sequence of Chlorobium tepidum TLS, a photosynthetic,
RT anaerobic, green-sulfur bacterium.";
RL Proc. Natl. Acad. Sci. U.S.A. 99:9509-9514(2002).
RN [2] {ECO:0000305}
RP PROTEIN SEQUENCE OF 28-39, FUNCTION, CATALYTIC ACTIVITY, COFACTOR,
RP BIOPHYSICOCHEMICAL PROPERTIES, SUBUNIT, INTERACTION WITH CT1020,
RP SUBCELLULAR LOCATION, MASS SPECTROMETRY, POTENTIOMETRIC TITRATION OF SOXA
RP AND THE SOXAX-CT1020 COMPLEX, AND SIGNAL.
RC STRAIN=ATCC 49652 / DSM 12025 / NBRC 103806 / TLS
RC {ECO:0000269|PubMed:18641134};
RX PubMed=18641134; DOI=10.1128/jb.00634-08;
RA Ogawa T., Furusawa T., Nomura R., Seo D., Hosoya-Matsuda N., Sakurai H.,
RA Inoue K.;
RT "SoxAX binding protein, a novel component of the thiosulfate-oxidizing
RT multienzyme system in the green sulfur bacterium Chlorobium tepidum.";
RL J. Bacteriol. 190:6097-6110(2008).
CC -!- FUNCTION: C-type monoheme cytochrome, which is part of the SoxAX
CC cytochrome complex involved in sulfur oxidation. The SoxAX complex
CC catalyzes the formation of a heterodisulfide bond between the conserved
CC cysteine residue on a sulfur carrier SoxYZ complex subunit SoxY and
CC thiosulfate or other inorganic sulfur substrates. This leads to the
CC liberation of two electrons, which may be transferred from the SoxAX
CC complex to another cytochrome c and which then may be used for
CC reductive CO(2) fixation. {ECO:0000250|UniProtKB:Q939U1,
CC ECO:0000269|PubMed:18641134}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=2 Fe(III)-[cytochrome c] + L-cysteinyl-[SoxY protein] +
CC thiosulfate = 2 Fe(II)-[cytochrome c] + 2 H(+) + S-sulfosulfanyl-L-
CC cysteinyl-[SoxY protein]; Xref=Rhea:RHEA:56720, Rhea:RHEA-COMP:10350,
CC Rhea:RHEA-COMP:14328, Rhea:RHEA-COMP:14399, Rhea:RHEA-COMP:14691,
CC ChEBI:CHEBI:15378, ChEBI:CHEBI:29033, ChEBI:CHEBI:29034,
CC ChEBI:CHEBI:29950, ChEBI:CHEBI:33542, ChEBI:CHEBI:139321; EC=2.8.5.2;
CC Evidence={ECO:0000269|PubMed:18641134};
CC -!- CATALYTIC ACTIVITY:
CC Reaction=2 Fe(III)-[cytochrome c] + S-sulfanyl-L-cysteinyl-[SoxY
CC protein] + thiosulfate = 2 Fe(II)-[cytochrome c] + 2 H(+) + S-(2-
CC sulfodisulfanyl)-L-cysteinyl-[SoxY protein]; Xref=Rhea:RHEA:51224,
CC Rhea:RHEA-COMP:10350, Rhea:RHEA-COMP:14399, Rhea:RHEA-COMP:14689,
CC Rhea:RHEA-COMP:14690, ChEBI:CHEBI:15378, ChEBI:CHEBI:29033,
CC ChEBI:CHEBI:29034, ChEBI:CHEBI:33542, ChEBI:CHEBI:61963,
CC ChEBI:CHEBI:140664; EC=2.8.5.2;
CC Evidence={ECO:0000269|PubMed:18641134};
CC -!- COFACTOR:
CC Name=heme; Xref=ChEBI:CHEBI:30413;
CC Evidence={ECO:0000269|PubMed:18641134};
CC Note=Binds 1 heme group per subunit. {ECO:0000269|PubMed:18641134};
CC -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC Kinetic parameters:
CC KM=0.17 mM for thiosulfate using purified SoxAX-CT1020, SoxYZ and
CC SoxB in the assay system (at pH 6.0) {ECO:0000269|PubMed:18641134};
CC pH dependence:
CC Optimum pH is 6.0-6.5. {ECO:0000269|PubMed:18641134};
CC Redox potential:
CC E(0) is less than -550 mV (at pH 10.0).
CC {ECO:0000269|PubMed:18641134};
CC Temperature dependence:
CC Optimum temperature is 55-60 degrees Celsius.
CC {ECO:0000269|PubMed:18641134};
CC -!- SUBUNIT: Heterodimer of SoxA and SoxX. The SoxAX complex interacts with
CC CT1020, SoxAX-binding protein SaxB (SoxK); this interaction seems to be
CC between SoxA and CT1020 and stimulates catalytic activity of the SoxAX
CC complex. {ECO:0000250|UniProtKB:D7A6E5, ECO:0000269|PubMed:18641134}.
CC -!- SUBCELLULAR LOCATION: Periplasm {ECO:0000269|PubMed:18641134}.
CC -!- PTM: Cysteine persulfide at Cys-247. {ECO:0000250|UniProtKB:Q8RLX0}.
CC -!- MASS SPECTROMETRY: Mass=29918; Method=MALDI; Note=The measured mass is
CC that of mature SoxA with a heme bound and with a cysteine persulfide
CC modification.; Evidence={ECO:0000269|PubMed:18641134};
CC -!- SIMILARITY: Belongs to the SoxA family. {ECO:0000255}.
CC ---------------------------------------------------------------------------
CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC ---------------------------------------------------------------------------
DR EMBL; AE006470; AAM72253.1; -; Genomic_DNA.
DR RefSeq; NP_661911.1; NC_002932.3.
DR RefSeq; WP_010932698.1; NC_002932.3.
DR AlphaFoldDB; Q8KDM7; -.
DR SMR; Q8KDM7; -.
DR STRING; 194439.CT1019; -.
DR EnsemblBacteria; AAM72253; AAM72253; CT1019.
DR KEGG; cte:CT1019; -.
DR PATRIC; fig|194439.7.peg.927; -.
DR eggNOG; COG3258; Bacteria.
DR HOGENOM; CLU_079910_1_0_10; -.
DR OMA; RTMQHRL; -.
DR OrthoDB; 1297285at2; -.
DR Proteomes; UP000001007; Chromosome.
DR GO; GO:0070069; C:cytochrome complex; IDA:UniProtKB.
DR GO; GO:0042597; C:periplasmic space; IDA:UniProtKB.
DR GO; GO:0009055; F:electron transfer activity; IDA:UniProtKB.
DR GO; GO:0020037; F:heme binding; IDA:UniProtKB.
DR GO; GO:0005506; F:iron ion binding; IDA:UniProtKB.
DR GO; GO:0046872; F:metal ion binding; IDA:UniProtKB.
DR GO; GO:0016491; F:oxidoreductase activity; IDA:UniProtKB.
DR GO; GO:0016669; F:oxidoreductase activity, acting on a sulfur group of donors, cytochrome as acceptor; IDA:UniProtKB.
DR GO; GO:0046982; F:protein heterodimerization activity; IPI:UniProtKB.
DR GO; GO:0004792; F:thiosulfate sulfurtransferase activity; IDA:UniProtKB.
DR GO; GO:0019417; P:sulfur oxidation; IDA:UniProtKB.
DR Gene3D; 1.10.760.10; -; 2.
DR InterPro; IPR036909; Cyt_c-like_dom_sf.
DR InterPro; IPR025710; SoxA.
DR PIRSF; PIRSF038455; SoxA; 1.
DR SUPFAM; SSF46626; SSF46626; 2.
DR TIGRFAMs; TIGR04484; thiosulf_SoxA; 1.
PE 1: Evidence at protein level;
KW Direct protein sequencing; Disulfide bond; Electron transport; Heme; Iron;
KW Metal-binding; Periplasm; Reference proteome; Signal; Transferase;
KW Transport.
FT SIGNAL 1..27
FT /evidence="ECO:0000269|PubMed:18641134"
FT CHAIN 28..286
FT /note="L-cysteine S-thiosulfotransferase subunit SoxA"
FT /id="PRO_0000423491"
FT DOMAIN 180..286
FT /note="Cytochrome c"
FT /evidence="ECO:0000255, ECO:0000305"
FT ACT_SITE 247
FT /note="Cysteine persulfide intermediate"
FT /evidence="ECO:0000250|UniProtKB:D7A6E5"
FT BINDING 200
FT /ligand="heme"
FT /ligand_id="ChEBI:CHEBI:30413"
FT /note="covalent"
FT /evidence="ECO:0000250|UniProtKB:D7A6E5"
FT BINDING 204
FT /ligand="heme"
FT /ligand_id="ChEBI:CHEBI:30413"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT /evidence="ECO:0000250|UniProtKB:D7A6E5"
FT BINDING 243
FT /ligand="substrate"
FT /evidence="ECO:0000250|UniProtKB:Q939U1"
FT BINDING 247
FT /ligand="heme"
FT /ligand_id="ChEBI:CHEBI:30413"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT /evidence="ECO:0000250|UniProtKB:D7A6E5"
FT DISULFID 106..137
FT /evidence="ECO:0000250|UniProtKB:Q8RLX0"
SQ SEQUENCE 286 AA; 32134 MW; 5730860F4E78F770 CRC64;
MKKTIQRGLF TGALVLMTAM TAKPANAEVN YQALVDADVK AFQGFFRKEF PDVKLEDFGN
GVYALDEDAR KQWKEMEEFP PYELDVEAGK ALFNKPFANG KSLASCFPNG GAVRGMYPYF
DEKRKEVVTL EMAINECRVA NGEKPYAWEK GDIARVSAYI ASISRGQKVD VKVKSKAAYD
AYMKGKKFFY AKRGQLNMSC SGCHMEYAGR HLRAEIISPA LGHTTHFPVF RSKWGEIGTL
HRRYAGCSNN IGAKPFAPQS EEYRDLEFFQ TVMSNGLKYN GPASRK
