ID   SSRP_NITWN              Reviewed;         157 AA.
AC   Q3SRA4;
DT   15-JAN-2008, integrated into UniProtKB/Swiss-Prot.
DT   11-OCT-2005, sequence version 1.
DT   25-MAY-2022, entry version 102.
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=Nwi_1927;
OS   Nitrobacter winogradskyi (strain ATCC 25391 / DSM 10237 / CIP 104748 /
OS   NCIMB 11846 / Nb-255).
OC   Bacteria; Proteobacteria; Alphaproteobacteria; Hyphomicrobiales;
OC   Bradyrhizobiaceae; Nitrobacter.
OX   NCBI_TaxID=323098;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=ATCC 25391 / DSM 10237 / CIP 104748 / NCIMB 11846 / Nb-255;
RX   PubMed=16517654; DOI=10.1128/aem.72.3.2050-2063.2006;
RA   Starkenburg S.R., Chain P.S.G., Sayavedra-Soto L.A., Hauser L., Land M.L.,
RA   Larimer F.W., Malfatti S.A., Klotz M.G., Bottomley P.J., Arp D.J.,
RA   Hickey W.J.;
RT   "Genome sequence of the chemolithoautotrophic nitrite-oxidizing bacterium
RT   Nitrobacter winogradskyi Nb-255.";
RL   Appl. Environ. Microbiol. 72:2050-2063(2006).
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; CP000115; ABA05187.1; -; Genomic_DNA.
DR   RefSeq; WP_011315183.1; NC_007406.1.
DR   AlphaFoldDB; Q3SRA4; -.
DR   SMR; Q3SRA4; -.
DR   STRING; 323098.Nwi_1927; -.
DR   EnsemblBacteria; ABA05187; ABA05187; Nwi_1927.
DR   KEGG; nwi:Nwi_1927; -.
DR   eggNOG; COG0691; Bacteria.
DR   HOGENOM; CLU_108953_0_1_5; -.
DR   OMA; WTNHSAR; -.
DR   OrthoDB; 1720952at2; -.
DR   Proteomes; UP000002531; 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..157
FT                   /note="SsrA-binding protein"
FT                   /id="PRO_1000002094"
FT   REGION          133..157
FT                   /note="Disordered"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
FT   COMPBIAS        133..152
FT                   /note="Basic and acidic residues"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
SQ   SEQUENCE   157 AA;  18008 MW;  79E5B4C6F6600070 CRC64;
     MADKGERAIK VVAENRKARF NYAIEDTVEA GIALTGTEVK SIRNGKTTIA ESYADSKNGE
     IWLINSNIPE YLQANRFNHE PKRPRKLLLH RKQINKLMGA VDREGMTLIP LKLYFNERGR
     AKLLLAIAKG KKLHDKRESE KKRDWGREKG RLLRARG