ID   LEXA_ALBFT              Reviewed;         224 AA.
AC   Q21U48;
DT   18-MAR-2008, integrated into UniProtKB/Swiss-Prot.
DT   18-APR-2006, sequence version 1.
DT   03-AUG-2022, entry version 99.
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=Rfer_2994;
OS   Albidiferax ferrireducens (strain ATCC BAA-621 / DSM 15236 / T118)
OS   (Rhodoferax ferrireducens).
OC   Bacteria; Proteobacteria; Betaproteobacteria; Burkholderiales;
OC   Comamonadaceae; Rhodoferax.
OX   NCBI_TaxID=338969;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=ATCC BAA-621 / DSM 15236 / T118;
RA   Copeland A., Lucas S., Lapidus A., Barry K., Detter J.C.,
RA   Glavina del Rio T., Hammon N., Israni S., Pitluck S., Brettin T., Bruce D.,
RA   Han C., Tapia R., Gilna P., Kiss H., Schmutz J., Larimer F., Land M.,
RA   Kyrpides N., Ivanova N., Richardson P.;
RT   "Complete sequence of chromosome of Rhodoferax ferrireducens DSM 15236.";
RL   Submitted (FEB-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; CP000267; ABD70705.1; -; Genomic_DNA.
DR   RefSeq; WP_011465271.1; NC_007908.1.
DR   AlphaFoldDB; Q21U48; -.
DR   SMR; Q21U48; -.
DR   STRING; 338969.Rfer_2994; -.
DR   MEROPS; S24.001; -.
DR   EnsemblBacteria; ABD70705; ABD70705; Rfer_2994.
DR   KEGG; rfr:Rfer_2994; -.
DR   eggNOG; COG1974; Bacteria.
DR   HOGENOM; CLU_066192_45_3_4; -.
DR   OMA; HVWLLPH; -.
DR   OrthoDB; 1933795at2; -.
DR   Proteomes; UP000008332; 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..224
FT                   /note="LexA repressor"
FT                   /id="PRO_0000322756"
FT   DNA_BIND        31..51
FT                   /note="H-T-H motif"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   ACT_SITE        142
FT                   /note="For autocatalytic cleavage activity"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   ACT_SITE        179
FT                   /note="For autocatalytic cleavage activity"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   SITE            107..108
FT                   /note="Cleavage; by autolysis"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
SQ   SEQUENCE   224 AA;  24620 MW;  2AC72EC89CC4F465 CRC64;
     MLGSPKLTAR QQQILDLIQN AITLTGSPPT RAEIATELGF RSANAAEEHL QALARKGAIE
     LVSGTSRGIR LKSEALRSIN ESRSKQFPLS LPGLSQLMLP LIGRVAAGSP ILAQEHIDQT
     YYVESSLFQR KPDYLLKVRG MSMRDAGIMD GDLLAVQSTR DAKNGQIVVA RLGDEVTVKR
     FRRTKDLIEL CPENPDYQII VVEPGEPFEI EGLAVGLIRN TMLM