ID   IBPB_YERPA              Reviewed;         154 AA.
AC   Q1C3K9;
DT   15-JAN-2008, integrated into UniProtKB/Swiss-Prot.
DT   11-JUL-2006, sequence version 1.
DT   25-MAY-2022, entry version 80.
DE   RecName: Full=Small heat shock protein IbpB {ECO:0000255|HAMAP-Rule:MF_02001};
DE   AltName: Full=16 kDa heat shock protein B {ECO:0000255|HAMAP-Rule:MF_02001};
GN   Name=ibpB {ECO:0000255|HAMAP-Rule:MF_02001}; OrderedLocusNames=YPA_3001;
OS   Yersinia pestis bv. Antiqua (strain Antiqua).
OC   Bacteria; Proteobacteria; Gammaproteobacteria; Enterobacterales;
OC   Yersiniaceae; Yersinia.
OX   NCBI_TaxID=360102;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=Antiqua;
RX   PubMed=16740952; DOI=10.1128/jb.00124-06;
RA   Chain P.S.G., Hu P., Malfatti S.A., Radnedge L., Larimer F., Vergez L.M.,
RA   Worsham P., Chu M.C., Andersen G.L.;
RT   "Complete genome sequence of Yersinia pestis strains Antiqua and Nepal516:
RT   evidence of gene reduction in an emerging pathogen.";
RL   J. Bacteriol. 188:4453-4463(2006).
CC   -!- FUNCTION: Associates with aggregated proteins, together with IbpA, to
CC       stabilize and protect them from irreversible denaturation and extensive
CC       proteolysis during heat shock and oxidative stress. Aggregated proteins
CC       bound to the IbpAB complex are more efficiently refolded and
CC       reactivated by the ATP-dependent chaperone systems ClpB and
CC       DnaK/DnaJ/GrpE. Its activity is ATP-independent. {ECO:0000255|HAMAP-
CC       Rule:MF_02001}.
CC   -!- SUBUNIT: Homodimer. Forms homomultimers of about 100-150 subunits at
CC       optimal growth temperatures. Conformation changes to oligomers at high
CC       temperatures or high ionic concentrations. The decrease in size of the
CC       multimers is accompanied by an increase in chaperone activity.
CC       {ECO:0000255|HAMAP-Rule:MF_02001}.
CC   -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000255|HAMAP-Rule:MF_02001}.
CC   -!- DOMAIN: The N- and C-terminal flexible termini are involved in
CC       oligomerization and in the binding of non-native substrate proteins,
CC       and are essential for chaperone activity. {ECO:0000255|HAMAP-
CC       Rule:MF_02001}.
CC   -!- SIMILARITY: Belongs to the small heat shock protein (HSP20) family.
CC       {ECO:0000255|HAMAP-Rule:MF_02001, ECO:0000255|PROSITE-
CC       ProRule:PRU00285}.
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; CP000308; ABG14963.1; -; Genomic_DNA.
DR   RefSeq; WP_002209635.1; NZ_CP009906.1.
DR   AlphaFoldDB; Q1C3K9; -.
DR   SMR; Q1C3K9; -.
DR   EnsemblBacteria; ABG14963; ABG14963; YPA_3001.
DR   GeneID; 66843676; -.
DR   KEGG; ypa:YPA_3001; -.
DR   OMA; KESEYLH; -.
DR   Proteomes; UP000001971; Chromosome.
DR   GO; GO:0005737; C:cytoplasm; IEA:UniProtKB-SubCell.
DR   GO; GO:0050821; P:protein stabilization; IEA:UniProtKB-UniRule.
DR   CDD; cd06470; ACD_IbpA-B_like; 1.
DR   Gene3D; 2.60.40.790; -; 1.
DR   HAMAP; MF_02001; HSP20_IbpB; 1.
DR   InterPro; IPR002068; A-crystallin/Hsp20_dom.
DR   InterPro; IPR037913; ACD_IbpA/B.
DR   InterPro; IPR008978; HSP20-like_chaperone.
DR   InterPro; IPR022848; HSP20_IbpB.
DR   Pfam; PF00011; HSP20; 1.
DR   SUPFAM; SSF49764; SSF49764; 1.
DR   PROSITE; PS01031; SHSP; 1.
PE   3: Inferred from homology;
KW   Chaperone; Cytoplasm; Stress response.
FT   CHAIN           1..154
FT                   /note="Small heat shock protein IbpB"
FT                   /id="PRO_1000022033"
FT   DOMAIN          26..137
FT                   /note="sHSP"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00285"
SQ   SEQUENCE   154 AA;  17489 MW;  F03AD1D39FE6A0C4 CRC64;
     MRNYDLSPLL RQWIGFDKLA STMQGGQEPQ GFPPYNIEKT DDNHYRISLA LAGFKQSELD
     IEVEGPRLTV RGKPTPVEKQ VEYLHQGLVR KEFSLTFTLA EHLNVDNAQF ENGLLHIDLL
     RQVPEALQPQ RIAIGSATPQ ERQVLESPEA PDQQ