ID   LEXA_SHEFN              Reviewed;         204 AA.
AC   Q089E2;
DT   15-JAN-2008, integrated into UniProtKB/Swiss-Prot.
DT   31-OCT-2006, sequence version 1.
DT   03-AUG-2022, entry version 95.
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=Sfri_0260;
OS   Shewanella frigidimarina (strain NCIMB 400).
OC   Bacteria; Proteobacteria; Gammaproteobacteria; Alteromonadales;
OC   Shewanellaceae; Shewanella.
OX   NCBI_TaxID=318167;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=NCIMB 400;
RG   US DOE Joint Genome Institute;
RA   Copeland A., Lucas S., Lapidus A., Barry K., Detter J.C.,
RA   Glavina del Rio T., Hammon N., Israni S., Dalin E., Tice H., Pitluck S.,
RA   Fredrickson J.K., Kolker E., McCuel L.A., DiChristina T., Nealson K.H.,
RA   Newman D., Tiedje J.M., Zhou J., Romine M.F., Culley D.E., Serres M.,
RA   Chertkov O., Brettin T., Bruce D., Han C., Tapia R., Gilna P., Schmutz J.,
RA   Larimer F., Land M., Hauser L., Kyrpides N., Mikhailova N., Richardson P.;
RT   "Complete sequence of Shewanella frigidimarina NCIMB 400.";
RL   Submitted (AUG-2006) to the EMBL/GenBank/DDBJ databases.
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; CP000447; ABI70123.1; -; Genomic_DNA.
DR   RefSeq; WP_011635750.1; NC_008345.1.
DR   AlphaFoldDB; Q089E2; -.
DR   SMR; Q089E2; -.
DR   STRING; 318167.Sfri_0260; -.
DR   MEROPS; S24.001; -.
DR   EnsemblBacteria; ABI70123; ABI70123; Sfri_0260.
DR   KEGG; sfr:Sfri_0260; -.
DR   eggNOG; COG1974; Bacteria.
DR   HOGENOM; CLU_066192_45_3_6; -.
DR   OMA; HVWLLPH; -.
DR   OrthoDB; 1933795at2; -.
DR   Proteomes; UP000000684; 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..204
FT                   /note="LexA repressor"
FT                   /id="PRO_1000001336"
FT   DNA_BIND        28..48
FT                   /note="H-T-H motif"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   ACT_SITE        121
FT                   /note="For autocatalytic cleavage activity"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   ACT_SITE        158
FT                   /note="For autocatalytic cleavage activity"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   SITE            86..87
FT                   /note="Cleavage; by autolysis"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
SQ   SEQUENCE   204 AA;  22591 MW;  793FB5F98E44B7C1 CRC64;
     MRPLTPRQAE ILDLIKNNIA ETGMPPTRAE IANRLGFKSA NAAEEHLKAL AKKGFIEIMP
     GTSRGIRLPQ EEQVETGLPL IGQVAAGEPI LAQEHVEQYY QVDPNMFKPA ADFLLRVRGD
     SMKNIGILEG DLLAVHKMQQ ARNGQVVVAR VDDDVTVKRF EQKGNVIYLH AENEDYNPIK
     VDLSCQSLTI EGLAVGVIRN GDWL