AC   MF_00306;
DC   Protein; auto
TR   HAMAP; MF_00306; -; 1; level=0
XX
Names: SRP54
XX
ID   SRP54
case <OC:Archaea>
DE   RecName: Full=Signal recognition particle 54 kDa protein;
DE            Short=SRP54;
DE            EC=3.6.5.4;
GN   Name=srp54;
else case <OC:Bacteria>
DE   RecName: Full=Signal recognition particle protein;
DE            EC=3.6.5.4;
DE   AltName: Full=Fifty-four homolog;
GN   Name=ffh;
end case
XX
case <OC:Archaea>
CC   -!- FUNCTION: Involved in targeting and insertion of nascent membrane
CC       proteins into the cytoplasmic membrane. Binds to the hydrophobic signal
CC       sequence of the ribosome-nascent chain (RNC) as it emerges from the
CC       ribosomes. The SRP-RNC complex is then targeted to the cytoplasmic
CC       membrane where it interacts with the SRP receptor FtsY.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=GTP + H2O = GDP + H(+) + phosphate; Xref=Rhea:RHEA:19669,
CC         ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:37565,
CC         ChEBI:CHEBI:43474, ChEBI:CHEBI:58189; EC=3.6.5.4;
CC   -!- SUBUNIT: Part of the signal recognition particle protein translocation
CC       system, which is composed of SRP and FtsY. Archaeal SRP consists of a
CC       7S RNA molecule of 300 nucleotides and two protein subunits: SRP54 and
CC       SRP19.
else case <OC:Pseudomonadota>
CC   -!- FUNCTION: Involved in targeting and insertion of nascent membrane
CC       proteins into the cytoplasmic membrane. Binds to the hydrophobic signal
CC       sequence of the ribosome-nascent chain (RNC) as it emerges from the
CC       ribosomes. The SRP-RNC complex is then targeted to the cytoplasmic
CC       membrane where it interacts with the SRP receptor FtsY. Interaction
CC       with FtsY leads to the transfer of the RNC complex to the Sec
CC       translocase for insertion into the membrane, the hydrolysis of GTP by
CC       both Ffh and FtsY, and the dissociation of the SRP-FtsY complex into
CC       the individual components.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=GTP + H2O = GDP + H(+) + phosphate; Xref=Rhea:RHEA:19669,
CC         ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:37565,
CC         ChEBI:CHEBI:43474, ChEBI:CHEBI:58189; EC=3.6.5.4;
CC   -!- SUBUNIT: Part of the signal recognition particle protein translocation
CC       system, which is composed of SRP and FtsY. SRP is a ribonucleoprotein
CC       composed of Ffh and a 4.5S RNA molecule.
else
CC   -!- FUNCTION: Involved in targeting and insertion of nascent membrane
CC       proteins into the cytoplasmic membrane. Binds to the hydrophobic signal
CC       sequence of the ribosome-nascent chain (RNC) as it emerges from the
CC       ribosomes. The SRP-RNC complex is then targeted to the cytoplasmic
CC       membrane where it interacts with the SRP receptor FtsY.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=GTP + H2O = GDP + H(+) + phosphate; Xref=Rhea:RHEA:19669,
CC         ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:37565,
CC         ChEBI:CHEBI:43474, ChEBI:CHEBI:58189; EC=3.6.5.4;
CC   -!- SUBUNIT: Part of the signal recognition particle protein translocation
CC       system, which is composed of SRP and FtsY.
end case
CC   -!- SUBCELLULAR LOCATION: Cytoplasm. Note=The SRP-RNC complex is targeted
CC       to the cytoplasmic membrane.
CC   -!- DOMAIN: Composed of three domains: the N-terminal N domain, which is
CC       responsible for interactions with the ribosome, the central G domain,
CC       which binds GTP, and the C-terminal M domain, which binds the RNA and
CC       the signal sequence of the RNC.
CC   -!- SIMILARITY: Belongs to the GTP-binding SRP family. SRP54 subfamily.
XX
DR   Pfam; PF00448; SRP54; 1; trigger=no
DR   Pfam; PF02881; SRP54_N; 1; trigger=no
DR   Pfam; PF02978; SRP_SPB; 1; trigger=no
DR   PROSITE; PS00300; SRP54; 1; trigger=no
DR   NCBIfam; TIGR00959; Ffh; 1; trigger=no
XX
KW   Cytoplasm
KW   Signal recognition particle
KW   GTP-binding
KW   Hydrolase
KW   Nucleotide-binding
KW   Ribonucleoprotein
KW   RNA-binding
XX
GO   GO:0005525; F:GTP binding
GO   GO:0003924; F:GTPase activity
case <OC:Archaea>
GO   GO:0008312; F:7S RNA binding
else case <OC:Bacteria>
GO   GO:0003723; F:RNA binding
end case
GO   GO:0006612; P:protein targeting to membrane
GO   GO:0048500; C:signal recognition particle
GO   GO:1990904; C:ribonucleoprotein complex
XX
FT   From: SRP54_METJA (Q57565)
FT   BINDING         107..114
FT                   /ligand="GTP"
FT                   /ligand_id="ChEBI:CHEBI:37565"
FT   Condition: G-x-x-G-x(1,3)-G-K-T
FT   BINDING         188..192
FT                   /ligand="GTP"
FT                   /ligand_id="ChEBI:CHEBI:37565"
FT   Condition: D-[ST]-[AS]-G-R
FT   BINDING         247..250
FT                   /ligand="GTP"
FT                   /ligand_id="ChEBI:CHEBI:37565"
FT   Condition: x-[KR]-x-D
XX
Size: 430-525;
Related: None;
Template: P0AGD7; O29633; P37105; O07347; Q977V2;
Scope:
 Bacteria
 Archaea
Fusion:
 Nter: None
 Cter: None
Duplicate: None
Plasmid: None
Comments: None
XX
# Revision 1.35 2023/06/01
//