AC   MF_00015;
DC   Protein; auto
TR   HAMAP; MF_00015; -; 1; level=0
XX
Names: LexA
XX
ID   LEXA
DE   RecName: Full=LexA repressor;
DE            EC=3.4.21.88;
GN   Name=lexA;
XX
case <OC:Enterobacterales>
CC   -!- FUNCTION: Represses a number of genes involved in the response to DNA
CC       damage (SOS response), including recA and lexA. Binds to the 16 bp
CC       palindromic sequence 5'-CTGTATATATATACAG-3'. In the presence of single-
CC       stranded DNA, RecA interacts with LexA causing an autocatalytic
CC       cleavage which disrupts the DNA-binding part of LexA, leading to
CC       derepression of the SOS regulon and eventually DNA repair.
else
CC   -!- FUNCTION: Represses a number of genes involved in the response to DNA
CC       damage (SOS response), including recA and lexA. In the presence of
CC       single-stranded DNA, RecA interacts with LexA causing an autocatalytic
CC       cleavage which disrupts the DNA-binding part of LexA, leading to
CC       derepression of the SOS regulon and eventually DNA repair.
end case
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=Hydrolysis of Ala-|-Gly bond in repressor LexA.; EC=3.4.21.88;
CC   -!- SUBUNIT: Homodimer.
CC   -!- SIMILARITY: Belongs to the peptidase S24 family.
XX
DR   Pfam; PF01726; LexA_DNA_bind; 1; trigger=no
DR   Pfam; PF00717; Peptidase_S24; 1; trigger=no
DR   PRINTS; PR00726; LEXASERPTASE; 1; trigger=no
DR   NCBIfam; TIGR00498; LexA; 1; trigger=no
XX
KW   Transcription
KW   Transcription regulation
KW   Repressor
KW   DNA-binding
KW   DNA damage
KW   Autocatalytic cleavage
KW   Hydrolase
KW   DNA replication
KW   DNA repair
KW   SOS response
XX
GO   GO:0003677; F:DNA binding
GO   GO:0004252; F:serine-type endopeptidase activity
GO   GO:0006281; P:DNA repair
GO   GO:0006260; P:DNA replication
GO   GO:0045892; P:negative regulation of DNA-templated transcription
GO   GO:0006974; P:DNA damage response
GO   GO:0009432; P:SOS response
XX
FT   From: LEXA_ECOLI (P0A7C2)
FT   DNA_BIND        28..48
FT                   /note="H-T-H motif"
FT   ACT_SITE        119
FT                   /note="For autocatalytic cleavage activity"
FT   Condition: S
FT   ACT_SITE        156
FT                   /note="For autocatalytic cleavage activity"
FT   Condition: K
FT   SITE            84..85
FT                   /note="Cleavage; by autolysis"
FT   Condition: A-G
XX
Size: 192-275;
Related: None;
Template: P31080; P0A7C2; Q9ZFA4;
Scope:
 Bacteria
Fusion:
 Nter: None
 Cter: None
Duplicate: in GEOSL, NOCFA, PSEPK, PSESM, XANAC, XANCP
Plasmid: None
Comments: None
XX
# Revision 1.45 2023/06/01
//