SPM_004485

Uniprot: A0A037UKH4
Description: single-stranded DNA-binding protein
EC number:
Annotation score: 2 out of 5
Miscellaneous [CC]:
Protein existence: Inferred from homology
Catalytic activity:
Cofactor:
Enzyme regulation:
Function [CC]: FUNCTION: Required for rescue of stalled ribosomes mediated by trans-translation. Binds to transfer-messenger RNA (tmRNA), required for stable association of tmRNA with ribosomes. tmRNA and SmpB together mimic tRNA shape, replacing the anticodon stem-loop with SmpB. tmRNA is encoded by the ssrA gene; the 2 termini fold to resemble tRNA(Ala) and it encodes a "tag peptide", a short internal open reading frame. During trans-translation Ala-aminoacylated tmRNA acts like a tRNA, entering the A-site of stalled ribosomes, displacing the stalled mRNA. The ribosome then switches to translate the ORF on the tmRNA; the nascent peptide is terminated with the "tag peptide" encoded by the tmRNA and targeted for degradation. The ribosome is freed to recommence translation, which seems to be the essential function of trans-translation. {ECO:0000256|HAMAP-Rule:MF_00023}.; FUNCTION: Required for rescue of stalled ribosomes mediated by trans-translation. Binds to transfer-messenger RNA (tmRNA), required for stable association of tmRNA with ribosomes. tmRNA and SmpB together mimic tRNA shape, replacing the anticodon stem-loop with SmpB. tmRNA is encoded by the ssrA gene; the 2 termini fold to resemble tRNA(Ala) and it encodes a 'tag peptide', a short internal open reading frame. During trans-translation Ala-aminoacylated tmRNA acts like a tRNA, entering the A-site of stalled ribosomes, displacing the stalled mRNA. The ribosome then switches to translate the ORF on the tmRNA; the nascent peptide is terminated with the 'tag peptide' encoded by the tmRNA and targeted for degradation. The ribosome is freed to recommence translation, which seems to be the essential function of trans-translation. {ECO:0000256|SAAS:SAAS00308991}.
Pathway:
Active site:
Binding site:
Calcium binding:
DNA binding:
Metal binding:
Nucleotide binding:
Site:
Gene names (primary): smpB
Gene names (synonym):
Mass: 17,005
Subunit structure [CC]:
Gene ontology (GO): cytoplasm [GO:0005737]; DNA binding [GO:0003677]; RNA binding [GO:0003723]; trans-translation [GO:0070929]
Gene ontology IDs: GO:0003677; GO:0003723; GO:0005737; GO:0070929
Chain:
Signal peptide:
Domain [CC]:
Sequence similarities: SIMILARITY: Belongs to the SmpB family. {ECO:0000256|HAMAP-Rule:MF_00023, ECO:0000256|SAAS:SAAS00543763}.
Protein families: SmpB family
Coiled coil:
Domain [FT]:
Motif:
Region:
EMBL: AGBZ02000003
ProteinModelPortal:
MEROPS:
EnsemblBacteria KO: KAI92429
UniPathway:
CDD:
Gene3D: cd09294
HAMAP: 2.40.280.10
InterPro: MF_00023
PANTHER: IPR023620;IPR000037;IPR020081
PIRSF:
PRINTS:
PROSITE:
Pfam: PS01317
ProDom: PF01668
SMART: PD004488
SUPFAM:
TIGRFAMs: SSF74982

57130-57562(-)

>nucleotide sequence
TTAATACTTCCGGCGTAAACGCTCATTATCCCGTTGTTTAATTGTTTCACGTTTATCATA
ATTCTTTTTCCCACGAACTAAAGCAATTTCTAATTTAGCATAATTATTTTTAAGATATAA
CTTTAACGGTACTAACGTTAAACGTTCTAATTTAATTCGTTGCAAAATTTTCTTAATTTC
TTTTTTATGTAAAAGCAATTTTCTAGTACGGTCAGCATCTGGCACGTATGCTGTTGAAAA
TTTATATTGAGCAATTATCATATTAATAACAAACGCCTCATTTTTACGAATAATAACAAA
CGCCTCATTAATTGATACATCATTATTCCGAATTGACTTAATCTCACTGCCTGTCAAAAC
AATGCCAGCTTCATAGGTTTCAATAATTTCATAATTATACCGTGCTTTTTTATTAACTGT
AATTGTCAACAT

>protein sequence
MLTITVNKKARYNYEIIETYEAGIVLTGSEIKSIRNNDVSINEAFVIIRKNEAFVINMII
AQYKFSTAYVPDADRTRKLLLHKKEIKKILQRIKLERLTLVPLKLYLKNNYAKLEIALVR
GKKNYDKRETIKQRDNERLRRKY