LexA

• Description: transcriptional repressor of the SOS regulon
  
  

Gene name	lexA
Synonyms	dinR
Essential	no
Product	transcriptional repressor of the SOS regulon
Function	regulation of DNA damage repair
Function and regulation of this protein in SubtiPathways: Phosphorelay
MW, pI	22 kDa, 5.155
Gene length, protein length	615 bp, 205 aa
Immediate neighbours	fosB, yneA
Get the DNA and protein sequences (Barbe et al., 2009)
Genetic context This image was kindly provided by SubtiList

The gene

Basic information

• Locus tag: BSU17850

Database entries

• DBTBS entry: [1]

• SubtiList entry: [2]

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity: Represses uvrB, dinB, dinC, recA genes and itself by binding to the 14 bp palindromic sequence 5'-CGAACNNNNGTTCG-3'. In the presence of single-stranded DNA, RecA interacts with LexA causing an autocatalytic cleavage which disrupts the DNA-binding part of LexA, leading to derepression of the SOS regulon and eventually DNA repair. (according to Swiss-Prot)

• Protein family: peptidase S24 family (according to Swiss-Prot)

• Paralogous protein(s):

Extended information on the protein

• Kinetic information:

• Domains:

• Modification:

• Cofactor(s):

• Effectors of protein activity:

• Interactions:

• Localization:

Database entries

• Structure: 1JHH (from E. coli, S119A mutant, 33% identity, 52% similarity) PubMed

• UniProt: P31080

• KEGG entry: [3]

• E.C. number:

Expression and regulation

• Operon: lexA PubMed

• Sigma factor: SigB PubMed

• Regulation:
  • induced upon DNA damage (LexA) PubMed

• Regulatory mechanism: autorepression
  • LexA: transcription repression PubMed

• Additional information:

Biological materials

• Mutant:

• Expression vector:

• lacZ fusion:

• GFP fusion:

• two-hybrid system:

• Antibody: