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Preprotein translocase SecY subunit superfamily

SCOP classification
Root:   SCOP hierarchy in SUPERFAMILY [ 0] (11)
Class:   Membrane and cell surface proteins and peptides [ 56835] (58)
Fold:   Preprotein translocase SecY subunit [ 103490]
Superfamily:   Preprotein translocase SecY subunit [ 103491]
Families:   Preprotein translocase SecY subunit [ 103492]


Superfamily statistics
Genomes (3,228) Uniprot 2018_03 genome PDB chains (SCOP 1.75)
Domains 4,214 28,733 2
Proteins 4,174 28,668 2


Functional annotation
General category Processes_IC
Detailed category Transport

Document:
Function annotation of SCOP domain superfamilies

Arabidopsis Plant Ontology (AP)

(show details)
AP termFDR (all)SDAP levelAnnotation (direct or inherited)
Plant ANatomical entity (PAN)cardinal part of multi-tissue plant structure0Least InformativeDirect
Plant ANatomical entity (PAN)flower0Least InformativeDirect
Plant ANatomical entity (PAN)leaf0Least InformativeDirect
Plant ANatomical entity (PAN)collective phyllome structure0Least InformativeDirect
Plant structure DEvelopment stage (PDE)LP.10 ten leaves visible stage0Least InformativeDirect
Plant structure DEvelopment stage (PDE)LP.08 eight leaves visible stage0Least InformativeDirect
Plant structure DEvelopment stage (PDE)LP.02 two leaves visible stage0Least InformativeDirect

Document: AP annotation of SCOP domains

InterPro annotation
Cross references IPR002208 SSF103491 Protein matches
Abstract

Secretion across the inner membrane in some Gram-negative bacteria occurs via the preprotein translocase pathway. Proteins are produced in the cytoplasm as precursors, and require a chaperone subunit to direct them to the translocase component. [PubMed2202721]. From there, the mature proteins are either targeted to the outer membrane, or remain as periplasmic proteins. The translocase protein subunits are encoded on the bacterial chromosome.

The translocase itself comprises 7 proteins, including a chaperone protein (SecB), an ATPase (SecA), an integral membrane complex (SecCY, SecE and SecG), and two additional membrane proteins that promote the release of the mature peptide into the periplasm (SecD and SecF) [PubMed2202721]. The chaperone protein SecB [PubMed11336818] is a highly acidic homotetrameric protein that exists as a "dimer of dimers" in the bacterial cytoplasm. SecB maintains preproteins in an unfolded state after translation, and targets these to the peripheral membrane protein ATPase SecA for secretion [PubMed10418149]. The structure of the Escherichia coli SecYEG assembly revealed a sandwich of two membranes interacting through the extensive cytoplasmic domains [PubMed12167867]. Each membrane is composed of dimers of SecYEG. The monomeric complex contains 15 transmembrane helices.

The eubacterial secY protein [PubMed1406280] interacts with the signal sequences of secretory proteins as well as with two other components of the protein translocation system: secA and secE. SecY is an integral plasma membrane protein of 419 to 492 amino acid residues that apparently contains 10 transmembrane (TM), 6 cytoplasmic and 5 periplasmic regions.

Cytoplasmic regions 2 and 3, and TM domains 1, 2, 4, 5, 7 and 10 are well conserved: the conserved cytoplasmic regions are believed to interact with cytoplasmic secretion factors, while the TM domains may participate in protein export [PubMed2110998]. Homologs of secY are found in archaebacteria [PubMed1764515]. SecY is also encoded in the chloroplast genome of some algae [PubMed1544427] where it could be involved in a prokaryotic-like protein export system across the two membranes of the chloroplast endoplasmic reticulum (CER) which is present in chromophyte and cryptophyte algae.


InterPro database


PDBeMotif information about ligands, sequence and structure motifs
Cross references PDB entries
Ligand binding statistics
Nucleic-acid binding statistics
Occurrence of secondary structure elements
Occurrence of small 3D structural motifs

PDBeMotif resource

Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation · Arabidopsis Plant Ontology (AP) ]

Internal database links

Browse genome assignments for this superfamily. The SUPERFAMILY hidden Markov model library has been used to carry out SCOP domain assignments to all genomes at the superfamily level.


Alignments of sequences to 4 models in this superfamily are available by clicking on the 'Alignments' icon above. PDB sequences less than 40% identical are shown by default, but any other sequence(s) may be aligned. Select PDB sequences, genome sequences, or paste in or upload your own sequences.


Browse and view proteins in genomes which have different domain combinations including a Preprotein translocase SecY subunit domain.


Examine the distribution of domain superfamilies, or families, across the major taxonomic kingdoms or genomes within a kingdom. This gives an immediate impression of how superfamilies, or families, are restricted to certain kingdoms of life.


Explore domain occurrence network where nodes represent genomes and edges are domain architectures (shared between genomes) containing the superfamily of interest.

There are 4 hidden Markov models representing the Preprotein translocase SecY subunit superfamily. Information on how the models are built, and plots showing hydrophobicity, match emmission probabilities and insertion/deletion probabilities can be inspected.


Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation · Arabidopsis Plant Ontology (AP) · Internal database links ]