ID   LEXA_GEOSW              Reviewed;         207 AA.
AC   C5D9K3;
DT   22-SEP-2009, integrated into UniProtKB/Swiss-Prot.
DT   28-JUL-2009, sequence version 1.
DT   03-AUG-2022, entry version 68.
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=GWCH70_1236;
OS   Geobacillus sp. (strain WCH70).
OC   Bacteria; Firmicutes; Bacilli; Bacillales; Bacillaceae; Geobacillus;
OC   unclassified Geobacillus.
OX   NCBI_TaxID=471223;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=WCH70;
RG   US DOE Joint Genome Institute;
RA   Lucas S., Copeland A., Lapidus A., Glavina del Rio T., Dalin E., Tice H.,
RA   Bruce D., Goodwin L., Pitluck S., Chertkov O., Brettin T., Detter J.C.,
RA   Han C., Larimer F., Land M., Hauser L., Kyrpides N., Mikhailova N.,
RA   Brumm P., Mead D.A., Richardson P.;
RT   "Complete sequence of chromosome of Geopacillus sp. WCH70.";
RL   Submitted (JUN-2009) 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; CP001638; ACS24089.1; -; Genomic_DNA.
DR   RefSeq; WP_015863561.1; NC_012793.1.
DR   AlphaFoldDB; C5D9K3; -.
DR   SMR; C5D9K3; -.
DR   STRING; 471223.GWCH70_1236; -.
DR   MEROPS; S24.001; -.
DR   EnsemblBacteria; ACS24089; ACS24089; GWCH70_1236.
DR   KEGG; gwc:GWCH70_1236; -.
DR   eggNOG; COG1974; Bacteria.
DR   HOGENOM; CLU_066192_45_1_9; -.
DR   OMA; HVWLLPH; -.
DR   OrthoDB; 1933795at2; -.
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; cd00090; HTH_ARSR; 1.
DR   CDD; cd06529; S24_LexA-like; 1.
DR   Gene3D; 1.10.10.10; -; 1.
DR   HAMAP; MF_00015; LexA; 1.
DR   InterPro; IPR011991; ArsR-like_HTH.
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; Repressor; SOS response; Transcription;
KW   Transcription regulation.
FT   CHAIN           1..207
FT                   /note="LexA repressor"
FT                   /id="PRO_1000201823"
FT   DNA_BIND        28..48
FT                   /note="H-T-H motif"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   ACT_SITE        129
FT                   /note="For autocatalytic cleavage activity"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   ACT_SITE        167
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   207 AA;  23086 MW;  8FD1CCE84F23EA41 CRC64;
     MTKLSKRQQQ ILDFIKKEVK TKGYPPSVRE IGEAVGLASS STVHGHLARL ESKGYIRRDP
     TKPRAIEILD ADFSASNQTD DVISVPIIGK VTAGQPITAI ENIEDYFPLP KRLVSSEDHV
     FMLEVMGDSM IEAGILDGDY VIVRQQQSAD NGDIVVAMTE DNEATVKRFF KEKDHIRLQP
     ENSNLEPIIV RDCTILGKVI GVYRVIH