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Protein Domain : IPR006200

Name  LexA repressor Short Name  LexA
Type  Family Description  This group of proteins are serine peptidases belong to MEROPS peptidase S24 (LexA family, clan SF). The family contains the LexA proteins. LexA represses around 20 genes of the cellular SOS response to DNA damage in Escherichia coli[]. Damage to cellular DNA results in inactivation of LexA, allowing transcription of the genes involved in DNA repair. In E. coli, this derepression of the DNA repair system is mediated by RecA, which binds to LexA upon interaction with single-stranded DNA. This results in inactivation of LexA by proteolytic self cleavage, disrupting the DNA-binding capabilities of LexA.LexA consists of around 200 amino acids, of which the first 90form the DNA-binding domain. The remaining residues form the protease domain, Ser-119 and Lys-156 being the active residues. The crystal structures of the wild type and several mutant forms of LexA reveal two distinct conformations: one compatible with cleavage, and the other in which the cleavage site is approximately 20 A from the catalytic centre. It is suggested that recA activates the self-cleavage of LexA and related proteins through selective stabilisation of the cleavable conformation [].

Publication Counts Displayer

0 Child Features

4 Contains

DB identifier Name Short Name Type
IPR011991 Winged helix-turn-helix DNA-binding domain WHTH_DNA-bd_dom Domain
IPR019759 Peptidase S24/S26A/S26B Peptidase_S24_S26 Domain
IPR015927 Peptidase S24/S26A/S26B/S26C Peptidase_S24_S26A/B/C Domain
IPR006199 LexA repressor, DNA-binding domain LexA_DNA-bd_dom Domain

2 Cross References

Identifier
Source . Name

Subject . Primary Identifier
TIGR00498 TIGRFAMs IPR006200
MF_00015 HAMAP IPR006200

2 Data Sets

Name URL
InterPro data set  
InterPro GO Annotation data set  

0 Found In

2 GO Annotation


Subject . Secondary Identifier

Subject . Name

Subject . Symbol

Ontology Term . Identifier

Ontology Term . Name
LexA repressor   GO:0004252 serine-type endopeptidase activity
LexA repressor   GO:0006508 proteolysis

2 Ontology Annotations


Subject . Secondary Identifier

Subject . Name

Subject . Symbol

Ontology Term . Identifier

Ontology Term . Name
LexA repressor   GO:0004252 serine-type endopeptidase activity
LexA repressor   GO:0006508 proteolysis

1 Parent Features

DB identifier Name Short Name Type
IPR006197 Peptidase S24, LexA-like Peptidase_S24_LexA Family

0 Proteins