ID   CHPB_ECOLI              Reviewed;         116 AA.
AC   P33647; Q2M680;
DT   01-FEB-1994, integrated into UniProtKB/Swiss-Prot.
DT   01-FEB-1994, sequence version 1.
DT   02-SEP-2026, entry version 156.
DE   RecName: Full=Endoribonuclease toxin ChpB;
DE            EC=3.1.-.-;
DE   AltName: Full=Toxin ChpB;
DE   AltName: Full=mRNA interferase ChpB;
GN   Name=chpB; Synonyms=chpBK, yjfE; OrderedLocusNames=b4225, JW4184;
OS   Escherichia coli (strain K12).
OC   Bacteria; Pseudomonadati; Pseudomonadota; Gammaproteobacteria;
OC   Enterobacterales; Enterobacteriaceae; Escherichia.
OX   NCBI_TaxID=83333;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA], FUNCTION, AND PROBABLE OPERON STRUCTURE.
RC   STRAIN=K12 / MC1000 / ATCC 39531;
RX   PubMed=8226627; DOI=10.1128/jb.175.21.6850-6856.1993;
RA   Masuda Y., Miyakawa K., Nishimura Y., Ohtsubo E.;
RT   "chpA and chpB, Escherichia coli chromosomal homologs of the pem locus
RT   responsible for stable maintenance of plasmid R100.";
RL   J. Bacteriol. 175:6850-6856(1993).
RN   [2]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=K12 / MG1655 / ATCC 47076;
RX   PubMed=7610040; DOI=10.1093/nar/23.12.2105;
RA   Burland V.D., Plunkett G. III, Sofia H.J., Daniels D.L., Blattner F.R.;
RT   "Analysis of the Escherichia coli genome VI: DNA sequence of the region
RT   from 92.8 through 100 minutes.";
RL   Nucleic Acids Res. 23:2105-2119(1995).
RN   [3]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=K12 / MG1655 / ATCC 47076;
RX   PubMed=9278503; DOI=10.1126/science.277.5331.1453;
RA   Blattner F.R., Plunkett G. III, Bloch C.A., Perna N.T., Burland V.,
RA   Riley M., Collado-Vides J., Glasner J.D., Rode C.K., Mayhew G.F.,
RA   Gregor J., Davis N.W., Kirkpatrick H.A., Goeden M.A., Rose D.J., Mau B.,
RA   Shao Y.;
RT   "The complete genome sequence of Escherichia coli K-12.";
RL   Science 277:1453-1462(1997).
RN   [4]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=K12 / W3110 / ATCC 27325 / DSM 5911;
RX   PubMed=16738553; DOI=10.1038/msb4100049;
RA   Hayashi K., Morooka N., Yamamoto Y., Fujita K., Isono K., Choi S.,
RA   Ohtsubo E., Baba T., Wanner B.L., Mori H., Horiuchi T.;
RT   "Highly accurate genome sequences of Escherichia coli K-12 strains MG1655
RT   and W3110.";
RL   Mol. Syst. Biol. 2:E1-E5(2006).
RN   [5]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 1-30.
RC   STRAIN=K12;
RX   PubMed=3525538; DOI=10.1016/s0021-9258(18)67610-0;
RA   Weiss D.L., Johnson D.I., Weith H.L., Somerville R.L.;
RT   "Structural analysis of the ileR locus of Escherichia coli K12.";
RL   J. Biol. Chem. 261:9966-9971(1986).
RN   [6]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 20-116.
RC   STRAIN=K12;
RX   PubMed=2848015; DOI=10.1128/jb.170.12.5901-5907.1988;
RA   Lahti R., Pitkaeranta T., Valve E., Ilta I., Kukko-Kalske E., Heinonen J.;
RT   "Cloning and characterization of the gene encoding inorganic
RT   pyrophosphatase of Escherichia coli K-12.";
RL   J. Bacteriol. 170:5901-5907(1988).
RN   [7]
RP   GENE MAPPING, AND DISRUPTION PHENOTYPE.
RC   STRAIN=K12 / W3110 / ATCC 27325 / DSM 5911;
RX   PubMed=8083180; DOI=10.1128/jb.176.18.5861-5863.1994;
RA   Masuda Y., Ohtsubo E.;
RT   "Mapping and disruption of the chpB locus in Escherichia coli.";
RL   J. Bacteriol. 176:5861-5863(1994).
RN   [8]
RP   FUNCTION, RNA CLEAVAGE, AND DISRUPTION PHENOTYPE.
RC   STRAIN=K12 / MG1655 / ATCC 47076;
RX   PubMed=12972253; DOI=10.1016/s0022-2836(03)00922-7;
RA   Christensen S.K., Pedersen K., Hansen F.G., Gerdes K.;
RT   "Toxin-antitoxin loci as stress-response-elements: ChpAK/MazF and ChpBK
RT   cleave translated RNAs and are counteracted by tmRNA.";
RL   J. Mol. Biol. 332:809-819(2003).
RN   [9]
RP   FUNCTION AS AN RNA ENDORIBONUCLEASE, SUBUNIT, AND INTERACTION WITH CHPS.
RX   PubMed=16413033; DOI=10.1016/j.jmb.2005.12.033;
RA   Kamphuis M.B., Bonvin A.M., Monti M.C., Lemonnier M., Munoz-Gomez A.,
RA   van den Heuvel R.H., Diaz-Orejas R., Boelens R.;
RT   "Model for RNA binding and the catalytic site of the RNase Kid of the
RT   bacterial parD toxin-antitoxin system.";
RL   J. Mol. Biol. 357:115-126(2006).
RN   [10]
RP   FUNCTION, AND ACTIVITY REGULATION.
RX   PubMed=21419338; DOI=10.1016/j.molcel.2011.02.023;
RA   Belitsky M., Avshalom H., Erental A., Yelin I., Kumar S., London N.,
RA   Sperber M., Schueler-Furman O., Engelberg-Kulka H.;
RT   "The Escherichia coli extracellular death factor EDF induces the
RT   endoribonucleolytic activities of the toxins MazF and ChpBK.";
RL   Mol. Cell 41:625-635(2011).
RN   [11]
RP   RETRACTED PAPER.
RC   STRAIN=K12 / MG1655 / ATCC 47076;
RX   PubMed=21788497; DOI=10.1073/pnas.1100186108;
RA   Maisonneuve E., Shakespeare L.J., Joergensen M.G., Gerdes K.;
RT   "Bacterial persistence by RNA endonucleases.";
RL   Proc. Natl. Acad. Sci. U.S.A. 108:13206-13211(2011).
RN   [12]
RP   RETRACTION NOTICE OF PUBMED:21788497.
RX   PubMed=29531044; DOI=10.1073/pnas.1803278115;
RA   Maisonneuve E., Shakespeare L.J., Joergensen M.G., Gerdes K.;
RL   Proc. Natl. Acad. Sci. U.S.A. 115:E2901-E2901(2018).
CC   -!- FUNCTION: Toxic component of a type II toxin-antitoxin (TA) system.
CC       ChpB is a sequence-specific mRNA and (weak) tmRNA endoribonuclease that
CC       inhibits protein synthesis and induces bacterial stasis. Cleavage is
CC       independent of the ribosome. Cleavage occurs at ACY sequences where Y
CC       is not C. The endoribonuclease activity is not as strong as that of
CC       MazF. The endoribonuclease activity (a toxin) is inhibited by its
CC       labile cognate antitoxin ChpS. Toxicity results when the levels of ChpS
CC       decrease in the cell, leading to mRNA degradation. Both ChpS and ChpB
CC       probably bind to the promoter region of the chpS-chpB operon to
CC       autoregulate their synthesis. {ECO:0000269|PubMed:12972253,
CC       ECO:0000269|PubMed:16413033, ECO:0000269|PubMed:21419338,
CC       ECO:0000269|PubMed:8226627}.
CC   -!- ACTIVITY REGULATION: Stimulated in vitro in a concentration-dependent
CC       fashion by extracellular death factor (EDF, a quorum sensing
CC       pentapeptide sequence NNWNN, probably produced from the zwf gene
CC       product glucose-6-phosphate 1-dehydrogenase), which is able to overcome
CC       inhibition by cognate antitoxin ChpS. {ECO:0000269|PubMed:21419338}.
CC   -!- SUBUNIT: Homodimer, interacts with ChpS, which inhibits the
CC       endoribonuclease activity. {ECO:0000269|PubMed:16413033}.
CC   -!- INDUCTION: Part of the chpS-chpB operon. {ECO:0000269|PubMed:8226627}.
CC   -!- DISRUPTION PHENOTYPE: No visible phenotype (PubMed:12972253,
CC       PubMed:8083180). {ECO:0000269|PubMed:12972253,
CC       ECO:0000269|PubMed:8083180}.
CC   -!- SIMILARITY: Belongs to the PemK/MazF family. {ECO:0000305}.
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DR   EMBL; D16451; BAA03920.1; -; Genomic_DNA.
DR   EMBL; M14018; -; NOT_ANNOTATED_CDS; Genomic_DNA.
DR   EMBL; U14003; AAA97122.1; -; Genomic_DNA.
DR   EMBL; U00096; AAC77182.1; -; Genomic_DNA.
DR   EMBL; M23550; -; NOT_ANNOTATED_CDS; Unassigned_DNA.
DR   EMBL; AP009048; BAE78226.1; -; Genomic_DNA.
DR   PIR; D49339; D49339.
DR   RefSeq; NP_418646.1; NC_000913.3.
DR   RefSeq; WP_000239577.1; NZ_CP009789.1.
DR   AlphaFoldDB; P33647; -.
DR   SMR; P33647; -.
DR   BioGRID; 4259311; 4.
DR   ComplexPortal; CPX-4063; ChpBS toxin-antitoxin complex.
DR   FunCoup; P33647; 121.
DR   STRING; 511145.b4225; -.
DR   jPOST; P33647; -.
DR   PaxDb; 511145-b4225; -.
DR   EnsemblBacteria; AAC77182; AAC77182; b4225.
DR   GeneID; 948747; -.
DR   KEGG; ecj:JW4184; -.
DR   KEGG; eco:b4225; -.
DR   KEGG; ecoc:C3026_22815; -.
DR   PATRIC; fig|511145.12.peg.4357; -.
DR   EchoBASE; EB2020; -.
DR   eggNOG; COG2337; Bacteria.
DR   HOGENOM; CLU_121823_2_1_6; -.
DR   InParanoid; P33647; -.
DR   OMA; IWHVNGD; -.
DR   OrthoDB; 9808744at2; -.
DR   PhylomeDB; P33647; -.
DR   BioCyc; EcoCyc:EG12096-MONOMER; -.
DR   BioCyc; MetaCyc:EG12096-MONOMER; -.
DR   PRO; PR:P33647; -.
DR   Proteomes; UP000000625; Chromosome.
DR   AbasyAtlas; P33647; -.
DR   GO; GO:0110001; C:toxin-antitoxin complex; IPI:ComplexPortal.
DR   GO; GO:0003677; F:DNA binding; IEA:InterPro.
DR   GO; GO:0004521; F:RNA endonuclease activity; IDA:UniProtKB.
DR   GO; GO:0016891; F:RNA endonuclease activity producing 5'-phosphomonoesters, hydrolytic mechanism; IDA:EcoCyc.
DR   GO; GO:0006402; P:mRNA catabolic process; IBA:GO_Central.
DR   GO; GO:0030308; P:negative regulation of cell growth; IMP:EcoCyc.
DR   GO; GO:0006355; P:regulation of DNA-templated transcription; NAS:ComplexPortal.
DR   GO; GO:0040008; P:regulation of growth; NAS:ComplexPortal.
DR   GO; GO:0043488; P:regulation of mRNA stability; IDA:UniProtKB.
DR   GO; GO:0016075; P:rRNA catabolic process; IBA:GO_Central.
DR   GO; GO:0044010; P:single-species biofilm formation; NAS:ComplexPortal.
DR   Gene3D; 2.30.30.110; -; 1.
DR   InterPro; IPR003477; PemK-like.
DR   InterPro; IPR011067; Plasmid_toxin/cell-grow_inhib.
DR   NCBIfam; NF007320; PRK09812.1; 1.
DR   PANTHER; PTHR33988; ENDORIBONUCLEASE MAZF-RELATED; 1.
DR   PANTHER; PTHR33988:SF3; ENDORIBONUCLEASE TOXIN CHPB-RELATED; 1.
DR   Pfam; PF02452; PemK_toxin; 1.
DR   SUPFAM; SSF50118; Cell growth inhibitor/plasmid maintenance toxic component; 1.
PE   1: Evidence at protein level;
KW   DNA-binding; Endonuclease; Hydrolase; Nuclease; Reference proteome;
KW   RNA-binding; Toxin-antitoxin system.
FT   CHAIN           1..116
FT                   /note="Endoribonuclease toxin ChpB"
FT                   /id="PRO_0000201899"
SQ   SEQUENCE   116 AA;  12492 MW;  4D641F3E302FCF58 CRC64;
     MVKKSEFERG DIVLVGFDPA SGHEQQGAGR PALVLSVQAF NQLGMTLVAP ITQGGNFARY
     AGFSVPLHCE EGDVHGVVLV NQVRMMDLHA RLAKRIGLAA DEVVEEALLR LQAVVE
//