ID   SSRP_CERS4              Reviewed;         157 AA.
AC   Q3IZG8;
DT   29-APR-2008, integrated into UniProtKB/Swiss-Prot.
DT   08-NOV-2005, sequence version 1.
DT   25-MAY-2022, entry version 90.
DE   RecName: Full=SsrA-binding protein {ECO:0000255|HAMAP-Rule:MF_00023};
DE   AltName: Full=Small protein B {ECO:0000255|HAMAP-Rule:MF_00023};
GN   Name=smpB {ECO:0000255|HAMAP-Rule:MF_00023}; OrderedLocusNames=RHOS4_24980;
GN   ORFNames=RSP_0883;
OS   Cereibacter sphaeroides (strain ATCC 17023 / DSM 158 / JCM 6121 / CCUG
OS   31486 / LMG 2827 / NBRC 12203 / NCIMB 8253 / ATH 2.4.1.) (Rhodobacter
OS   sphaeroides).
OC   Bacteria; Proteobacteria; Alphaproteobacteria; Rhodobacterales;
OC   Rhodobacteraceae; Cereibacter.
OX   NCBI_TaxID=272943;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=ATCC 17023 / DSM 158 / JCM 6121 / CCUG 31486 / LMG 2827 / NBRC 12203
RC   / NCIMB 8253 / ATH 2.4.1.;
RA   Copeland A., Lucas S., Lapidus A., Barry K., Detter J.C., Glavina T.,
RA   Hammon N., Israni S., Pitluck S., Richardson P., Mackenzie C.,
RA   Choudhary M., Larimer F., Hauser L.J., Land M., Donohue T.J., Kaplan S.;
RT   "Complete sequence of chromosome 1 of Rhodobacter sphaeroides 2.4.1.";
RL   Submitted (SEP-2005) to the EMBL/GenBank/DDBJ databases.
CC   -!- FUNCTION: Required for rescue of stalled ribosomes mediated by trans-
CC       translation. Binds to transfer-messenger RNA (tmRNA), required for
CC       stable association of tmRNA with ribosomes. tmRNA and SmpB together
CC       mimic tRNA shape, replacing the anticodon stem-loop with SmpB. tmRNA is
CC       encoded by the ssrA gene; the 2 termini fold to resemble tRNA(Ala) and
CC       it encodes a 'tag peptide', a short internal open reading frame. During
CC       trans-translation Ala-aminoacylated tmRNA acts like a tRNA, entering
CC       the A-site of stalled ribosomes, displacing the stalled mRNA. The
CC       ribosome then switches to translate the ORF on the tmRNA; the nascent
CC       peptide is terminated with the 'tag peptide' encoded by the tmRNA and
CC       targeted for degradation. The ribosome is freed to recommence
CC       translation, which seems to be the essential function of trans-
CC       translation. {ECO:0000255|HAMAP-Rule:MF_00023}.
CC   -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000255|HAMAP-Rule:MF_00023}.
CC       Note=The tmRNA-SmpB complex associates with stalled 70S ribosomes.
CC       {ECO:0000255|HAMAP-Rule:MF_00023}.
CC   -!- SIMILARITY: Belongs to the SmpB family. {ECO:0000255|HAMAP-
CC       Rule:MF_00023}.
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DR   EMBL; CP000143; ABA80066.1; -; Genomic_DNA.
DR   RefSeq; WP_002721091.1; NZ_CP030271.1.
DR   RefSeq; YP_353967.1; NC_007493.2.
DR   AlphaFoldDB; Q3IZG8; -.
DR   SMR; Q3IZG8; -.
DR   STRING; 272943.RSP_0883; -.
DR   EnsemblBacteria; ABA80066; ABA80066; RSP_0883.
DR   GeneID; 57471214; -.
DR   GeneID; 67447639; -.
DR   KEGG; rsp:RSP_0883; -.
DR   PATRIC; fig|272943.9.peg.2849; -.
DR   eggNOG; COG0691; Bacteria.
DR   OMA; WTNHSAR; -.
DR   PhylomeDB; Q3IZG8; -.
DR   Proteomes; UP000002703; Chromosome 1.
DR   GO; GO:0005737; C:cytoplasm; IEA:UniProtKB-SubCell.
DR   GO; GO:0003723; F:RNA binding; IEA:UniProtKB-UniRule.
DR   GO; GO:0070929; P:trans-translation; IEA:UniProtKB-UniRule.
DR   CDD; cd09294; SmpB; 1.
DR   Gene3D; 2.40.280.10; -; 1.
DR   HAMAP; MF_00023; SmpB; 1.
DR   InterPro; IPR023620; SmpB.
DR   InterPro; IPR000037; SsrA-bd_prot.
DR   InterPro; IPR020081; SsrA-bd_prot_CS.
DR   PANTHER; PTHR30308; PTHR30308; 1.
DR   Pfam; PF01668; SmpB; 1.
DR   SUPFAM; SSF74982; SSF74982; 1.
DR   TIGRFAMs; TIGR00086; smpB; 1.
DR   PROSITE; PS01317; SSRP; 1.
PE   3: Inferred from homology;
KW   Cytoplasm; Reference proteome; RNA-binding.
FT   CHAIN           1..157
FT                   /note="SsrA-binding protein"
FT                   /id="PRO_0000331084"
FT   REGION          136..157
FT                   /note="Disordered"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
SQ   SEQUENCE   157 AA;  18166 MW;  250A6F6C53C5561A CRC64;
     MAKHSDPNSK LIAENRRARF DYFIEEEIEA GIMLLGSEVK SLRQGGSNIG ESYASVEEGE
     LWLINGYIAP YLQAKTWGHE ERRKRKLLVS RRELARLWTA TAREGMTIVP IRMYFNDRGI
     VKLKIGIAKG KKLSDKRETS AKRDWSREKQ RLLKQNS