ID   SSRP_PROMA              Reviewed;         165 AA.
AC   Q7V9Q3;
DT   15-DEC-2003, integrated into UniProtKB/Swiss-Prot.
DT   01-OCT-2003, sequence version 1.
DT   25-MAY-2022, entry version 92.
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=Pro_1776;
OS   Prochlorococcus marinus (strain SARG / CCMP1375 / SS120).
OC   Bacteria; Cyanobacteria; Synechococcales; Prochlorococcaceae;
OC   Prochlorococcus.
OX   NCBI_TaxID=167539;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=SARG / CCMP1375 / SS120;
RX   PubMed=12917486; DOI=10.1073/pnas.1733211100;
RA   Dufresne A., Salanoubat M., Partensky F., Artiguenave F., Axmann I.M.,
RA   Barbe V., Duprat S., Galperin M.Y., Koonin E.V., Le Gall F., Makarova K.S.,
RA   Ostrowski M., Oztas S., Robert C., Rogozin I.B., Scanlan D.J.,
RA   Tandeau de Marsac N., Weissenbach J., Wincker P., Wolf Y.I., Hess W.R.;
RT   "Genome sequence of the cyanobacterium Prochlorococcus marinus SS120, a
RT   nearly minimal oxyphototrophic genome.";
RL   Proc. Natl. Acad. Sci. U.S.A. 100:10020-10025(2003).
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}.
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; AE017126; AAQ00820.1; -; Genomic_DNA.
DR   RefSeq; NP_876167.1; NC_005042.1.
DR   RefSeq; WP_011125925.1; NC_005042.1.
DR   AlphaFoldDB; Q7V9Q3; -.
DR   SMR; Q7V9Q3; -.
DR   STRING; 167539.Pro_1776; -.
DR   EnsemblBacteria; AAQ00820; AAQ00820; Pro_1776.
DR   GeneID; 54201105; -.
DR   KEGG; pma:Pro_1776; -.
DR   PATRIC; fig|167539.5.peg.1876; -.
DR   eggNOG; COG0691; Bacteria.
DR   HOGENOM; CLU_108953_0_1_3; -.
DR   OMA; WTNHSAR; -.
DR   OrthoDB; 1720952at2; -.
DR   Proteomes; UP000001420; 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..165
FT                   /note="SsrA-binding protein"
FT                   /id="PRO_0000103005"
FT   REGION          141..165
FT                   /note="Disordered"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
SQ   SEQUENCE   165 AA;  19019 MW;  2D5DAE2FFA5AD1FB CRC64;
     MSKARNNKKS KLSKAKSNRR LAENRYARHQ YEILEDIEAG IELLGTEVKS IRAGNVNLRD
     GFCLIREGSL LLHNVHISPF NNAGSFFNHE PLRVRKLLAH RKEINKLETQ VNRKGLTLVP
     LNIFLKGSWI KITIGLGKGR KLHDKRENEK RKQSEREVKS ALARY