STXB_SHIDY
ID STXB_SHIDY Reviewed; 89 AA.
AC Q7BQ98;
DT 04-DEC-2007, integrated into UniProtKB/Swiss-Prot.
DT 05-JUL-2004, sequence version 1.
DT 03-AUG-2022, entry version 87.
DE RecName: Full=Shiga toxin subunit B;
DE Flags: Precursor;
GN Name=stxB;
OS Shigella dysenteriae.
OC Bacteria; Proteobacteria; Gammaproteobacteria; Enterobacterales;
OC Enterobacteriaceae; Shigella.
OX NCBI_TaxID=622;
RN [1]
RP PROTEIN SEQUENCE.
RX PubMed=3771511; DOI=10.1016/s0021-9258(18)66961-3;
RA Seidah N.G., Donohue-Rolfe A., Lazure C., Auclair F., Keusch G.T.,
RA Chretien M.;
RT "Complete amino acid sequence of Shigella toxin B-chain. A novel
RT polypeptide containing 69 amino acids and one disulfide bridge.";
RL J. Biol. Chem. 261:13928-13931(1986).
RN [2]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX PubMed=3049254; DOI=10.1016/0378-1119(88)90398-8;
RA Kozlov Y.V., Kabishev A.A., Lukyanov E.V., Bayev A.A.;
RT "The primary structure of the operons coding for Shigella dysenteriae toxin
RT and temperature phage H30 shiga-like toxin.";
RL Gene 67:213-221(1988).
RN [3]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX PubMed=2830229; DOI=10.1128/jb.170.3.1116-1122.1988;
RA Strockbine N.A., Jackson M.P., Sung L.M., Holmes R.K., O'Brien A.D.;
RT "Cloning and sequencing of the genes for Shiga toxin from Shigella
RT dysenteriae type 1.";
RL J. Bacteriol. 170:1116-1122(1988).
RN [4]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RC STRAIN=3818 / Type 1;
RX PubMed=10594830; DOI=10.1046/j.1365-2958.1999.01669.x;
RA McDonough M.A., Butterton J.R.;
RT "Spontaneous tandem amplification and deletion of the Shiga toxin operon in
RT Shigella dysenteriae 1.";
RL Mol. Microbiol. 34:1058-1069(1999).
RN [5]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RC STRAIN=H2765-39/81 / Type 1;
RX PubMed=10948097; DOI=10.1128/iai.68.9.4856-4864.2000;
RA Unkmeir A., Schmidt H.;
RT "Structural analysis of phage-borne stx genes and their flanking sequences
RT in shiga toxin-producing Escherichia coli and Shigella dysenteriae type 1
RT strains.";
RL Infect. Immun. 68:4856-4864(2000).
RN [6]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 1-70.
RA Kozlov Y.V., Kabishev A.A., Fedchenko V.I., Bayev A.A.;
RT "Cloning and primary structure of Shigella toxin genes.";
RL Dokl. Biochem. 295:744-749(1987).
RN [7]
RP INDUCTION.
RX PubMed=6360895; DOI=10.1128/iai.43.1.195-201.1984;
RA Maurelli A.T., Blackmon B., Curtiss R. III;
RT "Temperature-dependent expression of virulence genes in Shigella species.";
RL Infect. Immun. 43:195-201(1984).
RN [8]
RP FUNCTION.
RX PubMed=2677606; DOI=10.1111/j.1365-2958.1989.tb00273.x;
RA Donohue-Rolfe A., Jacewicz M., Keusch G.T.;
RT "Isolation and characterization of functional Shiga toxin subunits and
RT renatured holotoxin.";
RL Mol. Microbiol. 3:1231-1236(1989).
RN [9]
RP BINDING TO RECEPTOR.
RX PubMed=9712788; DOI=10.1128/iai.66.9.4355-4366.1998;
RA Cooling L.L.W., Walker K.E., Gille T., Koerner T.A.W.;
RT "Shiga toxin binds human platelets via globotriaosylceramide (Pk antigen)
RT and a novel platelet glycosphingolipid.";
RL Infect. Immun. 66:4355-4366(1998).
RN [10]
RP MUTAGENESIS OF ASP-36; ASP-37; ASP-38; SER-58 AND LYS-73.
RX PubMed=2404947; DOI=10.1128/jb.172.2.653-658.1990;
RA Jackson M.P., Wadolkowski E.A., Weinstein D.L., Holmes R.K., O'Brien A.D.;
RT "Functional analysis of the Shiga toxin and Shiga-like toxin type II
RT variant binding subunits by using site-directed mutagenesis.";
RL J. Bacteriol. 172:653-658(1990).
RN [11]
RP MUTAGENESIS OF ARG-53; ALA-63 AND GLY-80.
RX PubMed=1991714; DOI=10.1128/jb.173.3.1151-1160.1991;
RA Perera L.P., Samuel J.E., Holmes R.K., O'Brien A.D.;
RT "Identification of three amino acid residues in the B subunit of Shiga
RT toxin and Shiga-like toxin type II that are essential for holotoxin
RT activity.";
RL J. Bacteriol. 173:1151-1160(1991).
RN [12]
RP MUTAGENESIS OF ARG-53 AND TRP-54.
RX PubMed=7768810; DOI=10.1128/jb.177.11.3128-3132.1995;
RA Jemal C., Haddad J.E., Begum D., Jackson M.P.;
RT "Analysis of Shiga toxin subunit association by using hybrid A polypeptides
RT and site-specific mutagenesis.";
RL J. Bacteriol. 177:3128-3132(1995).
RN [13]
RP CRYSTALLIZATION.
RX PubMed=8345529; DOI=10.1006/jmbi.1993.1421;
RA Kozlov Y.V., Chernaia M.M., Fraser M.E., James M.N.G.;
RT "Purification and crystallization of Shiga toxin from Shigella
RT dysenteriae.";
RL J. Mol. Biol. 232:704-706(1993).
RN [14]
RP X-RAY CRYSTALLOGRAPHY (2.5 ANGSTROMS) OF 21-89.
RX PubMed=7656009; DOI=10.1038/nsb0194-59;
RA Fraser M.E., Chernaia M.M., Kozlov Y.V., James M.N.G.;
RT "Crystal structure of the holotoxin from Shigella dysenteriae at 2.5 A
RT resolution.";
RL Nat. Struct. Biol. 1:59-64(1994).
RN [15]
RP X-RAY CRYSTALLOGRAPHY (2.5 ANGSTROMS) OF 21-89.
RX PubMed=15075327; DOI=10.1074/jbc.m401939200;
RA Fraser M.E., Fujinaga M., Cherney M.M., Melton-Celsa A.R., Twiddy E.M.,
RA O'Brien A.D., James M.N.G.;
RT "Structure of shiga toxin type 2 (Stx2) from Escherichia coli O157:H7.";
RL J. Biol. Chem. 279:27511-27517(2004).
CC -!- FUNCTION: The B subunit is responsible for the binding of the holotoxin
CC to specific receptors on the target cell surface, such as
CC globotriaosylceramide (Gb3) in human intestinal microvilli.
CC {ECO:0000269|PubMed:2677606}.
CC -!- SUBUNIT: Shiga toxin contains a single subunit A and five copies of
CC subunit B.
CC -!- INTERACTION:
CC Q7BQ98; Q7BQ99: stxA; NbExp=2; IntAct=EBI-1025922, EBI-1025915;
CC -!- INDUCTION: Maximal induction occurs at 37 degrees Celsius and in low-
CC iron environments. {ECO:0000269|PubMed:6360895}.
CC -!- DOMAIN: There are three Gb3-binding sites in each subunit B monomer,
CC allowing for a tighter binding to the target cell. Binding sites 1 and
CC 2 have higher binding affinities than site 3.
CC -!- SIMILARITY: Belongs to the StxB family. {ECO:0000305}.
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DR EMBL; M24352; AAA26539.1; -; Genomic_DNA.
DR EMBL; M19437; AAA98348.1; -; Genomic_DNA.
DR EMBL; AF153317; AAF28122.1; -; Genomic_DNA.
DR EMBL; AJ271153; CAC05623.1; -; Genomic_DNA.
DR EMBL; X07903; CAA30742.1; -; Genomic_DNA.
DR RefSeq; WP_000752026.1; NZ_UAUQ01000013.1.
DR PDB; 1DM0; X-ray; 2.50 A; B/C/D/E/F/G/H/I/J/K=21-89.
DR PDB; 1R4Q; X-ray; 2.50 A; B/C/D/E/F/G/H/I/J/K=21-89.
DR PDBsum; 1DM0; -.
DR PDBsum; 1R4Q; -.
DR AlphaFoldDB; Q7BQ98; -.
DR SMR; Q7BQ98; -.
DR DIP; DIP-36367N; -.
DR IntAct; Q7BQ98; 2.
DR ChEMBL; CHEMBL3856169; -.
DR BioCyc; MetaCyc:MON-18744; -.
DR EvolutionaryTrace; Q7BQ98; -.
DR GO; GO:0005576; C:extracellular region; IEA:InterPro.
DR GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
DR GO; GO:0019836; P:hemolysis by symbiont of host erythrocytes; IEA:InterPro.
DR InterPro; IPR008992; Enterotoxin.
DR InterPro; IPR003189; SLT_beta.
DR Pfam; PF02258; SLT_beta; 1.
DR SUPFAM; SSF50203; SSF50203; 1.
PE 1: Evidence at protein level;
KW 3D-structure; Direct protein sequencing; Disulfide bond; Signal; Toxin;
KW Virulence.
FT SIGNAL 1..20
FT CHAIN 21..89
FT /note="Shiga toxin subunit B"
FT /id="PRO_0000312305"
FT DISULFID 24..77
FT MUTAGEN 36
FT /note="D->N: Complete loss of cytotoxicity; when associated
FT with N-37."
FT /evidence="ECO:0000269|PubMed:2404947"
FT MUTAGEN 36
FT /note="D->N: No effect on cytotoxicity."
FT /evidence="ECO:0000269|PubMed:2404947"
FT MUTAGEN 37
FT /note="D->N: Complete loss of cytotoxicity; when associated
FT with N-36."
FT /evidence="ECO:0000269|PubMed:2404947"
FT MUTAGEN 37
FT /note="D->N: No effect on cytotoxicity."
FT /evidence="ECO:0000269|PubMed:2404947"
FT MUTAGEN 38
FT /note="D->N: No effect on cytotoxicity."
FT /evidence="ECO:0000269|PubMed:2404947"
FT MUTAGEN 53
FT /note="R->D: Loss of cytotoxicity."
FT /evidence="ECO:0000269|PubMed:1991714,
FT ECO:0000269|PubMed:7768810"
FT MUTAGEN 54
FT /note="W->G,F: 100-fold reduction in cytotoxicity."
FT /evidence="ECO:0000269|PubMed:7768810"
FT MUTAGEN 58
FT /note="S->P: No effect on cytotoxicity."
FT /evidence="ECO:0000269|PubMed:2404947"
FT MUTAGEN 63
FT /note="A->T: Great decrease in cytotoxicity."
FT /evidence="ECO:0000269|PubMed:1991714"
FT MUTAGEN 73
FT /note="K->I: 10-fold decrease in cytotoxicity."
FT /evidence="ECO:0000269|PubMed:2404947"
FT MUTAGEN 80
FT /note="G->D: Great decrease in cytotoxicity."
FT /evidence="ECO:0000269|PubMed:1991714"
FT STRAND 25..27
FT /evidence="ECO:0007829|PDB:1DM0"
FT STRAND 29..34
FT /evidence="ECO:0007829|PDB:1DM0"
FT STRAND 40..44
FT /evidence="ECO:0007829|PDB:1DM0"
FT STRAND 48..51
FT /evidence="ECO:0007829|PDB:1R4Q"
FT HELIX 54..65
FT /evidence="ECO:0007829|PDB:1DM0"
FT STRAND 69..72
FT /evidence="ECO:0007829|PDB:1DM0"
FT STRAND 86..89
FT /evidence="ECO:0007829|PDB:1DM0"
SQ SEQUENCE 89 AA; 9743 MW; C78F7795CCD7242E CRC64;
MKKTLLIAAS LSFFSASALA TPDCVTGKVE YTKYNDDDTF TVKVGDKELF TNRWNLQSLL
LSAQITGMTV TIKTNACHNG GGFSEVIFR
