ID   SSRP_STRGC              Reviewed;         155 AA.
AC   A8AW61;
DT   20-MAY-2008, integrated into UniProtKB/Swiss-Prot.
DT   23-OCT-2007, sequence version 1.
DT   25-MAY-2022, entry version 86.
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=SGO_0720;
OS   Streptococcus gordonii (strain Challis / ATCC 35105 / BCRC 15272 / CH1 /
OS   DL1 / V288).
OC   Bacteria; Firmicutes; Bacilli; Lactobacillales; Streptococcaceae;
OC   Streptococcus.
OX   NCBI_TaxID=467705;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=Challis / ATCC 35105 / BCRC 15272 / CH1 / DL1 / V288;
RX   PubMed=17720781; DOI=10.1128/jb.01023-07;
RA   Vickerman M.M., Iobst S., Jesionowski A.M., Gill S.R.;
RT   "Genome-wide transcriptional changes in Streptococcus gordonii in response
RT   to competence signaling peptide.";
RL   J. Bacteriol. 189:7799-7807(2007).
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; CP000725; ABV10118.1; -; Genomic_DNA.
DR   RefSeq; WP_002894882.1; NC_009785.1.
DR   AlphaFoldDB; A8AW61; -.
DR   SMR; A8AW61; -.
DR   STRING; 467705.SGO_0720; -.
DR   EnsemblBacteria; ABV10118; ABV10118; SGO_0720.
DR   GeneID; 61536847; -.
DR   KEGG; sgo:SGO_0720; -.
DR   eggNOG; COG0691; Bacteria.
DR   HOGENOM; CLU_108953_0_0_9; -.
DR   OMA; WTNHSAR; -.
DR   Proteomes; UP000001131; Chromosome.
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..155
FT                   /note="SsrA-binding protein"
FT                   /id="PRO_1000074376"
SQ   SEQUENCE   155 AA;  17827 MW;  C4E536610A09AF54 CRC64;
     MAKGEGKVVA QNKKARHDYT IVDTIEAGMV LTGTEIKSVR AARINLKDGF AQIKNGEAWL
     SNVHIAPYEE GNIWNQEPER RRKLLLHKKQ IQKLEQETKG TGMTLVPLKV YLKDGYAKLL
     LGLAKGKHDY DKRESIKRRE QNRDIARQMK NFNTR