SBI_STAAR
ID SBI_STAAR Reviewed; 437 AA.
AC Q6GE15;
DT 10-FEB-2009, integrated into UniProtKB/Swiss-Prot.
DT 19-JUL-2004, sequence version 1.
DT 25-MAY-2022, entry version 89.
DE RecName: Full=Immunoglobulin-binding protein Sbi;
DE Flags: Precursor;
GN Name=sbi; OrderedLocusNames=SAR2508;
OS Staphylococcus aureus (strain MRSA252).
OC Bacteria; Firmicutes; Bacilli; Bacillales; Staphylococcaceae;
OC Staphylococcus.
OX NCBI_TaxID=282458;
RN [1]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=MRSA252;
RX PubMed=15213324; DOI=10.1073/pnas.0402521101;
RA Holden M.T.G., Feil E.J., Lindsay J.A., Peacock S.J., Day N.P.J.,
RA Enright M.C., Foster T.J., Moore C.E., Hurst L., Atkin R., Barron A.,
RA Bason N., Bentley S.D., Chillingworth C., Chillingworth T., Churcher C.,
RA Clark L., Corton C., Cronin A., Doggett J., Dowd L., Feltwell T., Hance Z.,
RA Harris B., Hauser H., Holroyd S., Jagels K., James K.D., Lennard N.,
RA Line A., Mayes R., Moule S., Mungall K., Ormond D., Quail M.A.,
RA Rabbinowitsch E., Rutherford K.M., Sanders M., Sharp S., Simmonds M.,
RA Stevens K., Whitehead S., Barrell B.G., Spratt B.G., Parkhill J.;
RT "Complete genomes of two clinical Staphylococcus aureus strains: evidence
RT for the rapid evolution of virulence and drug resistance.";
RL Proc. Natl. Acad. Sci. U.S.A. 101:9786-9791(2004).
CC -!- FUNCTION: Plays a role in the inhibition of both the innate and
CC adaptive immune responses. Possesses two N-terminal domains that bind
CC the Fc region of IgG and two domains that form a tripartite complex
CC with complement factors C3b and CFH. By recruiting CFH and C3b, the
CC secreted form acts as a potent complement inhibitor of the alternative
CC pathway-mediated lysis. {ECO:0000250|UniProtKB:A6QJQ7}.
CC -!- SUBUNIT: Interacts (via sbi-I and sbi-II domains) with the Fc region of
CC mammalian immunoglobulin G (IgG) proteins. Interacts (via sbi-III and
CC sbi-IV domains) with host complement C3. Interacts (via sbi-III and
CC sbi-IV domains) with host CFH (By similarity). Interacts (via sbi-IV
CC domain) with beta-2-glycoprotein 1/APOH (By similarity).
CC {ECO:0000250|UniProtKB:A6QJQ7, ECO:0000250|UniProtKB:Q931F4}.
CC -!- SUBCELLULAR LOCATION: Secreted {ECO:0000250|UniProtKB:A6QJQ7}. Cell
CC membrane {ECO:0000250|UniProtKB:A6QJQ7}. Note=Occurs both
CC extracellularly and associated with the cytoplasmic membrane where only
CC the domains I and II are exposed to the extracellular media. Membrane
CC association occurs via binding to lipoteichoic acid.
CC {ECO:0000250|UniProtKB:A6QJQ7}.
CC -!- DOMAIN: Sbi-I and sbi-II domains provide protection only when anchored
CC to the cell surface, whereas only the secreted sbi-III and sbi-IV
CC domains are biologically active. {ECO:0000250|UniProtKB:A6QJQ7}.
CC -!- SIMILARITY: Belongs to the immunoglobulin-binding protein Sbi family.
CC {ECO:0000305}.
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DR EMBL; BX571856; CAG41488.1; -; Genomic_DNA.
DR RefSeq; WP_000792567.1; NC_002952.2.
DR AlphaFoldDB; Q6GE15; -.
DR SMR; Q6GE15; -.
DR KEGG; sar:SAR2508; -.
DR HOGENOM; CLU_051343_0_0_9; -.
DR OMA; NAHASEQ; -.
DR OrthoDB; 523258at2; -.
DR PRO; PR:Q6GE15; -.
DR Proteomes; UP000000596; Chromosome.
DR GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR GO; GO:0005886; C:plasma membrane; IEA:UniProtKB-SubCell.
DR GO; GO:0019864; F:IgG binding; IEA:UniProtKB-KW.
DR Gene3D; 1.10.10.1270; -; 1.
DR InterPro; IPR009063; Ig/albumin-bd_sf.
DR InterPro; IPR021657; IgG-binding_Sbi_dom_IV.
DR InterPro; IPR003132; Protein_A_Ig-bd.
DR InterPro; IPR041909; Sbi_C3_db_domIV.
DR Pfam; PF02216; B; 2.
DR Pfam; PF11621; Sbi-IV; 1.
DR SUPFAM; SSF46997; SSF46997; 2.
PE 3: Inferred from homology;
KW Cell membrane; IgG-binding protein; Membrane; Repeat; Secreted; Signal;
KW Virulence.
FT SIGNAL 1..29
FT /evidence="ECO:0000255"
FT CHAIN 30..437
FT /note="Immunoglobulin-binding protein Sbi"
FT /id="PRO_0000361888"
FT REPEAT 43..94
FT /note="B 1"
FT REPEAT 95..148
FT /note="B 2"
FT REPEAT 267..271
FT /note="2-1"
FT REPEAT 272..276
FT /note="2-2"
FT REPEAT 277..281
FT /note="2-3"
FT REPEAT 282..286
FT /note="2-4"
FT REPEAT 287..291
FT /note="2-5"
FT REPEAT 292..296
FT /note="2-6"
FT REPEAT 297..301
FT /note="2-7"
FT REPEAT 302..306
FT /note="2-8"
FT REGION 42..94
FT /note="Sbi-I"
FT REGION 103..153
FT /note="Sbi-II"
FT REGION 154..195
FT /note="Sbi-III"
FT REGION 196..253
FT /note="Sbi-IV"
FT REGION 266..295
FT /note="Disordered"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT REGION 267..306
FT /note="8 X 5 AA tandem repeat of P-[KQ]-[AISV]-[EKQ]-
FT [AKLSV]"
SQ SEQUENCE 437 AA; 50192 MW; B9487B788F719C67 CRC64;
MKNKYISKLL VGAATITLAT MISNGEAKAS ENTQQTSTKH QTTQNNYVTD QQKAFYQVLH
LKGITEEQRN QYIKTLREHP ERAQEVFSES LKDSKNPDRR VAQQNAFYNV LKNDNLTEQE
KNNYIAQIKE NPDRSQQVWV ESVQSSKAKE RQNIENADKA IKDFQDNKAP HDKSAAYEAN
SKLPKDLRDK NNRFVEKVSI EKAIVRHDER VKSANDAISK LNEKDSIENR RLAQREVNKA
PMDVQKHLQK QLDALVAQKD AEKKVAPKVE APQIQSPQIE KPKAESPKVE VPQIQSPKVE
VPQSKLLGYY QSLKDSFNYG YKYLTDTYKS YKEKYDTAKY YYNKYYQYKG LIDKTVLTTI
GSGYGSYIKP LEVSKESGNL AKSYAQVRNY VTESINTGKV LYAFYQKPEL VKTAIKAQET
ATTFKNALTG IFKSFWK
