ID   LEXA_SHELP              Reviewed;         205 AA.
AC   A3Q951;
DT   15-JAN-2008, integrated into UniProtKB/Swiss-Prot.
DT   17-APR-2007, sequence version 1.
DT   03-AUG-2022, entry version 103.
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=Shew_0127;
OS   Shewanella loihica (strain ATCC BAA-1088 / PV-4).
OC   Bacteria; Proteobacteria; Gammaproteobacteria; Alteromonadales;
OC   Shewanellaceae; Shewanella.
OX   NCBI_TaxID=323850;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=ATCC BAA-1088 / PV-4;
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   Chain P., Malfatti S., Shin M., Vergez L., Schmutz J., Larimer F., Land M.,
RA   Hauser L., Kyrpides N., Mikhailova N., Romine M.F., Serres G.,
RA   Fredrickson J., Tiedje J., Richardson P.;
RT   "Complete sequence of Shewanella loihica PV-4.";
RL   Submitted (MAR-2007) 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; CP000606; ABO21999.1; -; Genomic_DNA.
DR   RefSeq; WP_011863936.1; NC_009092.1.
DR   AlphaFoldDB; A3Q951; -.
DR   SMR; A3Q951; -.
DR   STRING; 323850.Shew_0127; -.
DR   MEROPS; S24.001; -.
DR   EnsemblBacteria; ABO21999; ABO21999; Shew_0127.
DR   KEGG; slo:Shew_0127; -.
DR   eggNOG; COG1974; Bacteria.
DR   HOGENOM; CLU_066192_45_3_6; -.
DR   OMA; HVWLLPH; -.
DR   OrthoDB; 1933795at2; -.
DR   Proteomes; UP000001558; 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..205
FT                   /note="LexA repressor"
FT                   /id="PRO_1000001337"
FT   DNA_BIND        28..48
FT                   /note="H-T-H motif"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   ACT_SITE        122
FT                   /note="For autocatalytic cleavage activity"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   ACT_SITE        159
FT                   /note="For autocatalytic cleavage activity"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   SITE            87..88
FT                   /note="Cleavage; by autolysis"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
SQ   SEQUENCE   205 AA;  22668 MW;  326689492A1DA062 CRC64;
     MRPLTPRQAE ILDLIKRNIA DTGMPPTRAE IARRLGFKSA NAAEEHLKAL AKKGCIEIMP
     GTSRGIKLTQ EEEPEDLGLP LIGQVAAGEP ILAQEHVEQH YQVDPSMFRP SADFLLRVRG
     DSMKDIGILE GDLLAVHKVE QARNGQIVVA RVEDDVTVKR FEKRGSTVYL HAENEEYSPI
     VVDLTTQSLS IEGLAVGVIR NGDWQ