ID LEXA_HISS2 Reviewed; 210 AA.
AC B0USF0;
DT 20-MAY-2008, integrated into UniProtKB/Swiss-Prot.
DT 08-APR-2008, sequence version 1.
DT 27-MAR-2024, entry version 95.
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=HSM_0711;
OS Histophilus somni (strain 2336) (Haemophilus somnus).
OC Bacteria; Pseudomonadota; Gammaproteobacteria; Pasteurellales;
OC Pasteurellaceae; Histophilus.
OX NCBI_TaxID=228400;
RN [1]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=2336;
RG US DOE Joint Genome Institute;
RA Siddaramappa S., Duncan A.J., Challacombe J.F., Rainey D., Gillaspy A.F.,
RA Carson M., Gipson J., Gipson M., Bruce D., Detter J.C., Han C.S., Land M.,
RA Tapia R., Thompson L.S., Orvis J., Zaitshik J., Barnes G., Brettin T.S.,
RA Dyer D.W., Inzana T.J.;
RT "Complete sequence of Haemophilus somnus 2336.";
RL Submitted (FEB-2008) 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; CP000947; ACA32376.1; -; Genomic_DNA.
DR RefSeq; WP_011608542.1; NC_010519.1.
DR AlphaFoldDB; B0USF0; -.
DR SMR; B0USF0; -.
DR STRING; 228400.HSM_0711; -.
DR MEROPS; S24.001; -.
DR GeneID; 31486997; -.
DR KEGG; hsm:HSM_0711; -.
DR HOGENOM; CLU_066192_45_3_6; -.
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 DNA-templated transcription; 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; 2.10.109.10; Umud Fragment, subunit A; 1.
DR Gene3D; 1.10.10.10; Winged helix-like DNA-binding domain superfamily/Winged helix DNA-binding domain; 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 NCBIfam; TIGR00498; lexA; 1.
DR PANTHER; PTHR33516; LEXA REPRESSOR; 1.
DR PANTHER; PTHR33516:SF2; LEXA REPRESSOR; 1.
DR Pfam; PF01726; LexA_DNA_bind; 1.
DR Pfam; PF00717; Peptidase_S24; 1.
DR PRINTS; PR00726; LEXASERPTASE.
DR SUPFAM; SSF51306; LexA/Signal peptidase; 1.
DR SUPFAM; SSF46785; Winged helix' DNA-binding domain; 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..210
FT /note="LexA repressor"
FT /id="PRO_1000074057"
FT DNA_BIND 31..51
FT /note="H-T-H motif"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT ACT_SITE 126
FT /note="For autocatalytic cleavage activity"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT ACT_SITE 163
FT /note="For autocatalytic cleavage activity"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
FT SITE 91..92
FT /note="Cleavage; by autolysis"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00015"
SQ SEQUENCE 210 AA; 23490 MW; FFA98AE62014E9EC CRC64;
MSSIKSLTTR QQEVFDLIKR HIESTGMPPT RVEISKELGF RSPNAAEEHL KALARKGVIE
IVSGVSRGIR LLTDIEEPEN EGLPLIGRVA AGEPILAEQH IEATYQVDAN MFKPQADFLL
KVYGQSMKDI GILDGDLLAV HSTKDIRNGQ IVVARIEDEV TVKRFERKGS VVYLHAENEE
FEPIVVDLTQ QPYFEIEGIA VGIIRNNAWM
//
