ID   LEXA_COLP3              Reviewed;         211 AA.
AC   Q48AA9;
DT   18-MAR-2008, integrated into UniProtKB/Swiss-Prot.
DT   13-SEP-2005, sequence version 1.
DT   03-AUG-2022, entry version 111.
DE   RecName: Full=LexA repressor {ECO:0000255|HAMAP-Rule:MF_00015};
DE            EC=3.4.21.88 {ECO:0000255|HAMAP-Rule:MF_00015};
GN   Name=lexA {ECO:0000255|HAMAP-Rule:MF_00015}; OrderedLocusNames=CPS_0237;
OS   Colwellia psychrerythraea (strain 34H / ATCC BAA-681) (Vibrio
OS   psychroerythus).
OC   Bacteria; Proteobacteria; Gammaproteobacteria; Alteromonadales;
OC   Colwelliaceae; Colwellia.
OX   NCBI_TaxID=167879;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=34H / ATCC BAA-681;
RX   PubMed=16043709; DOI=10.1073/pnas.0504766102;
RA   Methe B.A., Nelson K.E., Deming J.W., Momen B., Melamud E., Zhang X.,
RA   Moult J., Madupu R., Nelson W.C., Dodson R.J., Brinkac L.M.,
RA   Daugherty S.C., Durkin A.S., DeBoy R.T., Kolonay J.F., Sullivan S.A.,
RA   Zhou L., Davidsen T.M., Wu M., Huston A.L., Lewis M., Weaver B.,
RA   Weidman J.F., Khouri H., Utterback T.R., Feldblyum T.V., Fraser C.M.;
RT   "The psychrophilic lifestyle as revealed by the genome sequence of
RT   Colwellia psychrerythraea 34H through genomic and proteomic analyses.";
RL   Proc. Natl. Acad. Sci. U.S.A. 102:10913-10918(2005).
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.
CC       {ECO:0000255|HAMAP-Rule:MF_00015}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=Hydrolysis of Ala-|-Gly bond in repressor LexA.; EC=3.4.21.88;
CC         Evidence={ECO:0000255|HAMAP-Rule:MF_00015};
CC   -!- SUBUNIT: Homodimer. {ECO:0000255|HAMAP-Rule:MF_00015}.
CC   -!- SIMILARITY: Belongs to the peptidase S24 family. {ECO:0000255|HAMAP-
CC       Rule:MF_00015}.
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DR   EMBL; CP000083; AAZ27640.1; -; Genomic_DNA.
DR   RefSeq; WP_011041111.1; NC_003910.7.
DR   AlphaFoldDB; Q48AA9; -.
DR   SMR; Q48AA9; -.
DR   STRING; 167879.CPS_0237; -.
DR   MEROPS; S24.001; -.
DR   EnsemblBacteria; AAZ27640; AAZ27640; CPS_0237.
DR   KEGG; cps:CPS_0237; -.
DR   eggNOG; COG1974; Bacteria.
DR   HOGENOM; CLU_066192_45_3_6; -.
DR   OMA; HVWLLPH; -.
DR   OrthoDB; 1933795at2; -.
DR   Proteomes; UP000000547; Chromosome.
DR   GO; GO:0003677; F:DNA binding; IEA:UniProtKB-UniRule.
DR   GO; GO:0004252; F:serine-type endopeptidase activity; IEA:UniProtKB-UniRule.
DR   GO; GO:0006281; P:DNA repair; IEA:UniProtKB-UniRule.
DR   GO; GO:0006260; P:DNA replication; IEA:UniProtKB-UniRule.
DR   GO; GO:0045892; P:negative regulation of transcription, DNA-templated; IEA:UniProtKB-UniRule.
DR   GO; GO:0006508; P:proteolysis; IEA:InterPro.
DR   GO; GO:0009432; P:SOS response; IEA:UniProtKB-UniRule.
DR   CDD; cd06529; S24_LexA-like; 1.
DR   Gene3D; 1.10.10.10; -; 1.
DR   HAMAP; MF_00015; LexA; 1.
DR   InterPro; IPR006200; LexA.
DR   InterPro; IPR039418; LexA-like.
DR   InterPro; IPR036286; LexA/Signal_pep-like_sf.
DR   InterPro; IPR006199; LexA_DNA-bd_dom.
DR   InterPro; IPR006197; Peptidase_S24_LexA.
DR   InterPro; IPR015927; Peptidase_S24_S26A/B/C.
DR   InterPro; IPR036388; WH-like_DNA-bd_sf.
DR   InterPro; IPR036390; WH_DNA-bd_sf.
DR   Pfam; PF01726; LexA_DNA_bind; 1.
DR   Pfam; PF00717; Peptidase_S24; 1.
DR   PRINTS; PR00726; LEXASERPTASE.
DR   SUPFAM; SSF46785; SSF46785; 1.
DR   SUPFAM; SSF51306; SSF51306; 1.
DR   TIGRFAMs; TIGR00498; lexA; 1.
PE   3: Inferred from homology;
KW   Autocatalytic cleavage; DNA damage; DNA repair; DNA replication;
KW   DNA-binding; Hydrolase; Reference proteome; Repressor; SOS response;
KW   Transcription; Transcription regulation.
FT   CHAIN           1..211
FT                   /note="LexA repressor"
FT                   /id="PRO_0000322726"
FT   DNA_BIND        35..55
FT                   /note="H-T-H motif"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   ACT_SITE        128
FT                   /note="For autocatalytic cleavage activity"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   ACT_SITE        165
FT                   /note="For autocatalytic cleavage activity"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   SITE            93..94
FT                   /note="Cleavage; by autolysis"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
SQ   SEQUENCE   211 AA;  23540 MW;  C1E08A9B1126E81F CRC64;
     MIDSTTELRP LTKRQQQIYD LIKAKIQDTG MPPTRAEIAN FFGFKSANAA EEHLKALAKK
     GYIEMLAGTS RGIRLVEEML EAEGLPLIGR VAAGEPILAQ EHIEEHYKMD GNLFHPAADY
     LLRVNGESMK DIGILDGDLL AVHQTTEVQN GQVVVARVEN DVTVKRFKRE GNVVYLHAEN
     EDFSPIKVDL ANQEFNIEGI AVGIIRSGRW M