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LexA/Signal peptidase superfamily

SCOP classification
Root:   SCOP hierarchy in SUPERFAMILY [ 0] (11)
Class:   All beta proteins [ 48724] (174)
Fold:   LexA/Signal peptidase [ 51305]
Superfamily:   LexA/Signal peptidase [ 51306] (2)
Families:   LexA-related [ 51307] (3)
  Type 1 signal peptidase [ 51312]


Superfamily statistics
Genomes (3,166) Uniprot 2018_03 genome PDB chains (SCOP 1.75)
Domains 12,343 100,185 12
Proteins 12,250 98,934 12


Functional annotation
General category Information
Detailed category Transcription

Document:
Function annotation of SCOP domain superfamilies

Enzyme Commission (EC)

(show details)
EC termFDR (all)SDEO levelAnnotation (direct or inherited)
Enzyme Commission (EC)Acting on peptide bonds (peptide hydrolases)0Least InformativeDirect
Enzyme Commission (EC)Serine endopeptidases0Moderately InformativeDirect

Document: EC annotation of SCOP domains

Worm Phenotype (WP)

(show details) Document: WP annotation of SCOP domains

Yeast Phenotype (YP)

(show details)
YP termFDR (all)SDYP levelAnnotation (direct or inherited)
Yeast Phenotype (YP)resistance to chemicals0Least InformativeDirect

Document: YP annotation of SCOP domains

Xenopus Anatomy (XA)

(show details)
XA termFDR (all)SDXA levelAnnotation (direct or inherited)
Xenopus ANatomical entity (XAN)urogenital system0Least InformativeDirect
Xenopus ANatomical entity (XAN)germ cell0Moderately InformativeDirect
Xenopus DEvelopment stage (XDE)post-embryonic stage0Least InformativeDirect
Xenopus DEvelopment stage (XDE)climax stage0Moderately InformativeDirect

Document: XA annotation of SCOP domains

Arabidopsis Plant Ontology (AP)

(show details)
AP termFDR (all)SDAP levelAnnotation (direct or inherited)
Plant ANatomical entity (PAN)guard cell0Least InformativeDirect

Document: AP annotation of SCOP domains

Enzyme Commission (EC)

(show details)
EC termFDR (all)SDEC levelAnnotation (direct or inherited)
Enzyme Commission (EC)Hydrolases0Least InformativeDirect
Enzyme Commission (EC)Acting on peptide bonds (peptidases)0Moderately InformativeDirect
Enzyme Commission (EC)Serine endopeptidases0InformativeDirect

Document: EC annotation of SCOP domains

InterPro annotation
Cross references IPR015927 SSF51306 Protein matches
Abstract

This signature is associated with serine peptidases belong to MEROPS peptidase families: S24 (LexA family, clan SF); S26A (signal peptidase I), S26B (signalase) and S26C TraF peptidase.

The S26 family includes Escherichia coli signal peptidase, SPase, which is a membrane-bound endopeptidase, with two N-terminal transmembrane segments and a C-terminal catalytic region [PubMed9823901]. SPase functions to release proteins that have been translocated into the inner membrane from the cell interior, by cleaving off their signal peptides.

The S24 family includes:

  • the lambda repressor CI/C2 family and related bacterial prophage repressor proteins [PubMed10892750].
  • LexA, the repressor of genes in the cellular SOS response to DNA damage [PubMed11551506].
  • MucA and the related UmuD proteins, which are lesion-bypass DNA polymerases, induced in response to mitogenic DNA damage [PubMed8994967].
  • RulA, a component of the rulAB locus that confers resistance to UV.

All of these proteins, with the possible exception of RulA, interact with RecA, which activates self cleavage either derepressing transcription in the case of CI and LexA [PubMed10692372] or activating the lesion-bypass polymerase in the case of UmuD and MucA. UmuD'2, is the homodimeric component of DNA pol V, which is produced from UmuD by RecA-facilitated self-cleavage. The first 24 N-terminal residues of UmuD are removed; UmuD'2 is a DNA lesion bypass polymerase [PubMed10692372, PubMed11483531]. MucA [PubMed9925794, PubMed11016960], like UmuD, is a plasmid encoded a DNA polymerase (pol RI) which is converted into the active lesion-bypass polymerase by a self-cleavage reaction involving RecA [PubMed11114935]

This group of proteins also contains proteins not recognised as peptidases as well as those classified as non-peptidase homologues as they either have been found experimentally to be without peptidase activity, or lack amino acid residues that are believed to be essential for catalytic activity.


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 · Enzyme Commission (EC) · Worm Phenotype (WP) · Yeast Phenotype (YP) · Xenopus Anatomy (XA) · Arabidopsis Plant Ontology (AP) · Enzyme Commission (EC) ]

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 5 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 LexA/Signal peptidase 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 5 hidden Markov models representing the LexA/Signal peptidase 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 · Enzyme Commission (EC) · Worm Phenotype (WP) · Yeast Phenotype (YP) · Xenopus Anatomy (XA) · Arabidopsis Plant Ontology (AP) · Enzyme Commission (EC) · Internal database links ]