3.4.21.88	additional information	RecA protein and single-stranded DNA are required for activity being attributed to a Ser/Lys dyad. The LexA protein represses the SOS regulon, which regulates the genes involved in DNA repair. In the presence of single-stranded DNA, the RecA protein interacts with repressor LexA, causing it to undergo an autocatalytic cleavage which disrupts the DNA-binding part of the repressor, and inactivates it. The consequent derepression of the SOS regulon leads to DNA repair	
3.4.21.88	additional information	LexA repressor coordinately controls about 20 unlinked genes comprising the bacterial SOS response, an inducible DNA repair system, these genes are necessary for functions as diverse as mutagenesis, DNA repair, recombionation, cell division, and prophage induction, SOS response is activated upon autoproteolysis of LexA repressor into its two separate domains	
3.4.21.88	additional information	interaction of enzyme with DNA motifs recA and yebG. Dissociation rate is 0.045 per s for recA and 0.13 per s for yebG with short-ranged binding potentials showing a stiff hydrogen-bonding network between protein and DNA	
3.4.21.88	additional information	involved in SOS response to DNA damage through recA-lexA regulon	
3.4.21.88	additional information	Vibrio cholerae LexA coordinates CTX prophage gene expression, overview. CTXPhi genes require for virion production initiate transcription from the strong PA promoter, which is dually repressed in lysogens by the phage-encoded repressor RstR and the host-encoded SOS repressor LexA. RstR both positively and negatively autoregulates its own expression from this promoter. LexA is absolutely required for RstR-mediated activation of PR transcription. Mechanisms, detailed overview	
3.4.21.88	additional information	LexA binds to dinBox1 and to half-site dinBox1b in the SOS boxes in the lysogenic promoter P1 of phage GIL01. The dinBox1 is a 14-bp long sequence in the P1 promoter region that is similar to the consensus LexA binding site in Bacillus subtilis (CGAAC(n)4GTTCG). Transcription from promoter P1 is regulated by host LexA and phage-borne factors	
3.4.21.88	additional information	LexA-gp7 interaction forms a heterohexamer with 2:4 stoichiometry. Gp7 interacts with Bacillus thuringiensis LexA C-terminal domain	
3.4.21.88	additional information	Rhodobacter capsulatus LexA binds to the predicted promoter regions of lexA, recA, and cckA and represses cckA and recA transcription. Putative LexA binding sites are present 5' of SOS response gene homologues and the RcGTA regulatory gene cckA