ID   LEXA1_NOCFA             Reviewed;         216 AA.
AC   Q5YP21;
DT   01-FEB-2005, integrated into UniProtKB/Swiss-Prot.
DT   23-NOV-2004, sequence version 1.
DT   03-AUG-2022, entry version 105.
DE   RecName: Full=LexA repressor 1 {ECO:0000255|HAMAP-Rule:MF_00015};
DE            EC=3.4.21.88 {ECO:0000255|HAMAP-Rule:MF_00015};
GN   Name=lexA1 {ECO:0000255|HAMAP-Rule:MF_00015}; OrderedLocusNames=NFA_52180;
OS   Nocardia farcinica (strain IFM 10152).
OC   Bacteria; Actinobacteria; Corynebacteriales; Nocardiaceae; Nocardia.
OX   NCBI_TaxID=247156;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=IFM 10152;
RX   PubMed=15466710; DOI=10.1073/pnas.0406410101;
RA   Ishikawa J., Yamashita A., Mikami Y., Hoshino Y., Kurita H., Hotta K.,
RA   Shiba T., Hattori M.;
RT   "The complete genomic sequence of Nocardia farcinica IFM 10152.";
RL   Proc. Natl. Acad. Sci. U.S.A. 101:14925-14930(2004).
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}.
CC   ---------------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC   ---------------------------------------------------------------------------
DR   EMBL; AP006618; BAD60070.1; -; Genomic_DNA.
DR   RefSeq; WP_011211752.1; NC_006361.1.
DR   AlphaFoldDB; Q5YP21; -.
DR   SMR; Q5YP21; -.
DR   STRING; 247156.NFA_52180; -.
DR   MEROPS; S24.001; -.
DR   EnsemblBacteria; BAD60070; BAD60070; NFA_52180.
DR   GeneID; 61135794; -.
DR   KEGG; nfa:NFA_52180; -.
DR   eggNOG; COG1974; Bacteria.
DR   HOGENOM; CLU_066192_45_0_11; -.
DR   OMA; EGVFCGL; -.
DR   BioCyc; NFAR247156:NFA_RS25880-MON; -.
DR   Proteomes; UP000006820; 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..216
FT                   /note="LexA repressor 1"
FT                   /id="PRO_0000170060"
FT   DNA_BIND        38..58
FT                   /note="H-T-H motif"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   ACT_SITE        140
FT                   /note="For autocatalytic cleavage activity"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   ACT_SITE        177
FT                   /note="For autocatalytic cleavage activity"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT   SITE            105..106
FT                   /note="Cleavage; by autolysis"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
SQ   SEQUENCE   216 AA;  23535 MW;  B36B608435C9C4BF CRC64;
     MTDYDFEHLD TSALPVRQRR ILEVIRDWVV EHGYAPSTRQ IGAAVGLRSM SSVARHLRSL
     EERGFLRRGE GVARPIDVRL FLHGTAAAAP SEDAVTVPVV GDIAAGAPIL AEEHTDDLLT
     LPRELVGRGT VFALRVRGDS MIDAAICDGD TVVVRSQREA NSGDIVAAMI GEEATVKVFR
     RRNGHVLLEP RNPAYDVIDG DEAVILGKVV SVLRRI