ID   LEXA_SYMTH              Reviewed;         205 AA.
AC   Q67NM2;
DT   01-FEB-2005, integrated into UniProtKB/Swiss-Prot.
DT   11-OCT-2004, sequence version 1.
DT   03-NOV-2009, entry version 34.
DE   RecName: Full=LexA repressor;
DE            EC=3.4.21.88;
GN   Name=lexA; OrderedLocusNames=STH1736;
OS   Symbiobacterium thermophilum.
OC   Bacteria; Firmicutes; Clostridia; Clostridiales;
OC   Clostridiales Family XVIII. Incertae Sedis; Symbiobacterium.
OX   NCBI_TaxID=2734;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=T / IAM 14863;
RX   PubMed=15383646; DOI=10.1093/nar/gkh830;
RA   Ueda K., Yamashita A., Ishikawa J., Shimada M., Watsuji T.,
RA   Morimura K., Ikeda H., Hattori M., Beppu T.;
RT   "Genome sequence of Symbiobacterium thermophilum, an uncultivable
RT   bacterium that depends on microbial commensalism.";
RL   Nucleic Acids Res. 32:4937-4944(2004).
CC   -!- FUNCTION: Represses a number of genes involved in the response to
CC       DNA damage (SOS response), including recA and lexA. In the
CC       presence of single-stranded DNA, recA interacts with lexA causing
CC       an autocatalytic cleavage which disrupts the DNA-binding part of
CC       lexA, leading to derepression of the SOS regulon and eventually
CC       DNA repair (By similarity).
CC   -!- CATALYTIC ACTIVITY: Hydrolysis of Ala-|-Gly bond in repressor
CC       lexA.
CC   -!- SUBUNIT: Homodimer (By similarity).
CC   -!- SIMILARITY: Belongs to the peptidase S24 family.
CC   -----------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see http://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution-NoDerivs License
CC   -----------------------------------------------------------------------
DR   EMBL; AP006840; BAD40721.1; -; Genomic_DNA.
DR   RefSeq; YP_075565.1; -.
DR   GeneID; 2979854; -.
DR   GenomeReviews; AP006840_GR; STH1736.
DR   KEGG; sth:STH1736; -.
DR   NMPDR; fig|292459.1.peg.1674; -.
DR   HOGENOM; Q67NM2; -.
DR   OMA; KVIGVFR; -.
DR   BioCyc; STHE292459:STH1736-MON; -.
DR   BRENDA; 3.4.21.88; 20615.
DR   GO; GO:0003677; F:DNA binding; IEA:HAMAP.
DR   GO; GO:0004252; F:serine-type endopeptidase activity; IEA:HAMAP.
DR   GO; GO:0006281; P:DNA repair; IEA:HAMAP.
DR   GO; GO:0006260; P:DNA replication; IEA:HAMAP.
DR   GO; GO:0045892; P:negative regulation of transcription, DNA-d...; IEA:HAMAP.
DR   GO; GO:0006508; P:proteolysis; IEA:InterPro.
DR   GO; GO:0009432; P:SOS response; IEA:HAMAP.
DR   GO; GO:0006350; P:transcription; IEA:UniProtKB-KW.
DR   HAMAP; MF_00015; -; 1.
DR   InterPro; IPR006199; LexA_DNA_bd.
DR   InterPro; IPR006200; Pept_S24_LexA.
DR   InterPro; IPR006197; Peptidase_S24_LexA_cons-reg.
DR   InterPro; IPR019759; Peptidase_S24_S26_cons-reg.
DR   InterPro; IPR011056; Peptidase_S24_S26A/B/C_b-rbn.
DR   InterPro; IPR011991; Wing_hlx_DNA_bd.
DR   Gene3D; G3DSA:2.10.109.10; Pept_S24_S26_C; 1.
DR   Gene3D; G3DSA:1.10.10.10; Wing_hlx_DNA_bd; 1.
DR   Pfam; PF01726; LexA_DNA_bind; 1.
DR   Pfam; PF00717; Peptidase_S24; 1.
DR   PRINTS; PR00726; LEXASERPTASE.
DR   TIGRFAMs; TIGR00498; lexA; 1.
PE   3: Inferred from homology;
KW   Autocatalytic cleavage; Complete proteome; DNA damage; DNA repair;
KW   DNA replication; DNA-binding; Hydrolase; Repressor; SOS response;
KW   Transcription; Transcription regulation.
FT   CHAIN         1    205       LexA repressor.
FT                                /FTId=PRO_0000170097.
FT   DNA_BIND     29     49       H-T-H motif (By similarity).
FT   ACT_SITE    128    128       For autocatalytic cleavage activity (By
FT                                similarity).
FT   ACT_SITE    165    165       For autocatalytic cleavage activity (By
FT                                similarity).
FT   SITE         91     92       Cleavage; by autolysis (By similarity).
SQ   SEQUENCE   205 AA;  23097 MW;  8CAD209C0B362258 CRC64;
     MPEPLTERQR QILQFIKDEI RTKGYPPSVR EIGEAIGLSS SSTVHGHMTR LEEKGYIRRD
     PTKPRAIEVL DGSHTQLKRT IAVPVVGRVT AGQPILAQES IEDHFPLPAD FVRADESELF
     FLTVQGDSMI EAGILDGDYV LVHRQQHANN GDIVVALIED EATVKRFFKE QDHIRLQPEN
     RFMDPIIVPD CQILGKVVGL VRRMG
//