ID   LEXA_XANP2              Reviewed;         237 AA.
AC   A7INJ8;
DT   24-MAR-2009, integrated into UniProtKB/Swiss-Prot.
DT   11-SEP-2007, sequence version 1.
DT   03-AUG-2022, entry version 87.
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=Xaut_4371;
OS   Xanthobacter autotrophicus (strain ATCC BAA-1158 / Py2).
OC   Bacteria; Proteobacteria; Alphaproteobacteria; Hyphomicrobiales;
OC   Xanthobacteraceae; Xanthobacter.
OX   NCBI_TaxID=78245;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=ATCC BAA-1158 / Py2;
RG   US DOE Joint Genome Institute;
RA   Copeland A., Lucas S., Lapidus A., Barry K., Glavina del Rio T., Hammon N.,
RA   Israni S., Dalin E., Tice H., Pitluck S., Sims D., Brettin T., Bruce D.,
RA   Detter J.C., Han C., Tapia R., Brainard J., Schmutz J., Larimer F.,
RA   Land M., Hauser L., Kyrpides N., Kim E., Ensigns S.A., Richardson P.;
RT   "Complete sequence of chromosome of Xanthobacter autotrophicus Py2.";
RL   Submitted (JUL-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; CP000781; ABS69592.1; -; Genomic_DNA.
DR   RefSeq; WP_012116341.1; NC_009720.1.
DR   AlphaFoldDB; A7INJ8; -.
DR   SMR; A7INJ8; -.
DR   STRING; 78245.Xaut_4371; -.
DR   MEROPS; S24.001; -.
DR   EnsemblBacteria; ABS69592; ABS69592; Xaut_4371.
DR   KEGG; xau:Xaut_4371; -.
DR   eggNOG; COG1974; Bacteria.
DR   HOGENOM; CLU_066192_45_2_5; -.
DR   OMA; HVWLLPH; -.
DR   OrthoDB; 1933795at2; -.
DR   PhylomeDB; A7INJ8; -.
DR   Proteomes; UP000002417; 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..237
FT                   /note="LexA repressor"
FT                   /id="PRO_1000089603"
FT   DNA_BIND        26..46
FT                   /note="H-T-H motif"
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   ACT_SITE        196
FT                   /note="For autocatalytic cleavage activity"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   SITE            123..124
FT                   /note="Cleavage; by autolysis"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
SQ   SEQUENCE   237 AA;  25887 MW;  AB25B4103DC6A70A CRC64;
     MLTRKQYDLL RFIHERLKET GVPPSFDEMK EALDLRSKSG IHRLITALEE RGFIRRLPNR
     ARALEVVRLP DSVAPGLATP RSASRGFSPS VIEGSLGKVR PAADDDEGAG QVVTVPVMGR
     IAAGSPISAI QTRSHTLNIP PEMLGSGEHF ALEVRGDSMI EAGILDGDTV LIRKCDTADT
     GDIIVALVDD EEATLKRLRK KGASIALEAA NPAYETRIFG PDRVRIQGRL IGLMRRY