P0AGD7 · SRP54_ECOLI

Function

function

Involved in targeting and insertion of nascent membrane proteins into the cytoplasmic membrane. Binds to the hydrophobic signal sequence of the ribosome-nascent chain (RNC) as it emerges from the ribosomes. The SRP-RNC complex is then targeted to the cytoplasmic membrane where it interacts with the SRP receptor FtsY. Interaction with FtsY leads to the transfer of the RNC complex to the Sec translocase for insertion into the membrane, the hydrolysis of GTP by both Ffh and FtsY, and the dissociation of the SRP-FtsY complex into the individual components.

Catalytic activity

Activity regulation

Conformation of the Ffh-FtsY complex and regulation of its GTPase activity are modulated by the 4.5S RNA. Formation of the FfH-FtsY complex leads to a mutual stimulation of both GTPases.

Features

Showing features for binding site.

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TypeIDPosition(s)Description
Binding site107-114GTP (UniProtKB | ChEBI)
Binding site190-194GTP (UniProtKB | ChEBI)
Binding site248-251GTP (UniProtKB | ChEBI)

GO annotations

AspectTerm
Cellular Componentcytosol
Cellular Componentribonucleoprotein complex
Cellular Componentsignal recognition particle
Molecular Function7S RNA binding
Molecular FunctionATP hydrolysis activity
Molecular FunctionGTP binding
Molecular FunctionGTPase activity
Biological Processprotein targeting to membrane
Biological ProcessSRP-dependent cotranslational protein targeting to membrane

Keywords

Enzyme and pathway databases

Protein family/group databases

Names & Taxonomy

Protein names

  • Recommended name
    Signal recognition particle protein
  • EC number
  • Alternative names
    • Fifty-four homolog
      (Ffh)
    • p48

Gene names

    • Name
      ffh
    • Ordered locus names
      b2610, JW5414

Organism names

  • Taxonomic identifier
  • Strains
    • K12 / W3110 / ATCC 27325 / DSM 5911
    • K12 / MG1655 / ATCC 47076
  • Taxonomic lineage
    Bacteria > Pseudomonadota > Gammaproteobacteria > Enterobacterales > Enterobacteriaceae > Escherichia

Accessions

  • Primary accession
    P0AGD7
  • Secondary accessions
    • P07019
    • P77007
    • P77008

Proteomes

Subcellular Location

Keywords

Phenotypes & Variants

Disruption phenotype

Essential; deletion experiments lead to loss of inner membrane protein targeting. Also leads to reduced targeting of lipoproteins Lpp and BRP.

PTM/Processing

Features

Showing features for chain.

TypeIDPosition(s)Description
ChainPRO_00001011531-453Signal recognition particle protein

Proteomic databases

PTM databases

Interaction

Subunit

Part of the signal recognition particle protein translocation system, which is composed of SRP and FtsY. SRP is a ribonucleoprotein composed of Ffh and a 4.5S RNA molecule. Metal ions are essential for the formation and stability of the SRP complex. Interacts with the ribosomes, via ribosomal protein L23. Interacts with FtsY.

Binary interactions

TypeEntry 1Entry 2Number of experimentsIntact
BINARY P0AGD7ftsY P1012110EBI-369938, EBI-549067
BINARY P0AGD7rpoH P0AGB34EBI-369938, EBI-555342

Protein-protein interaction databases

Family & Domains

Domain

Composed of three domains: the N-terminal N domain, which is responsible for interactions with the ribosome, the central G domain, which binds GTP, and the C-terminal M domain, which binds the RNA and the signal sequence of the RNC.

Sequence similarities

Belongs to the GTP-binding SRP family. SRP54 subfamily.

Phylogenomic databases

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    453
  • Mass (Da)
    49,787
  • Last updated
    2005-12-20 v1
  • Checksum
    E9C7A7101CC04D66
MFDNLTDRLSRTLRNISGRGRLTEDNVKDTLREVRMALLEADVALPVVREFINRVKEKAVGHEVNKSLTPGQEFVKIVRNELVAAMGEENQTLNLAAQPPAVVLMAGLQGAGKTTSVGKLGKFLREKHKKKVLVVSADVYRPAAIKQLETLAEQVGVDFFPSDVGQKPVDIVNAALKEAKLKFYDVLLVDTAGRLHVDEAMMDEIKQVHASINPVETLFVVDAMTGQDAANTAKAFNEALPLTGVVLTKVDGDARGGAALSIRHITGKPIKFLGVGEKTEALEPFHPDRIASRILGMGDVLSLIEDIESKVDRAQAEKLASKLKKGDGFDLNDFLEQLRQMKNMGGMASLMGKLPGMGQIPDNVKSQMDDKVLVRMEAIINSMTMKERAKPEIIKGSRKRRIAAGCGMQVQDVNRLLKQFDDMQRMMKKMKKGGMAKMMRSMKGMMPPGFPGR

Sequence caution

The sequence CAA25957.1 differs from that shown. Reason: Erroneous initiation Truncated N-terminus.

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
X01818
EMBL· GenBank· DDBJ
CAA25957.1
EMBL· GenBank· DDBJ
Genomic DNA Different initiation
U00096
EMBL· GenBank· DDBJ
AAC75659.1
EMBL· GenBank· DDBJ
Genomic DNA
AP009048
EMBL· GenBank· DDBJ
BAA16495.2
EMBL· GenBank· DDBJ
Genomic DNA

Genome annotation databases

Similar Proteins

Disclaimer

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