Nucleotide Sequence of the LexA Gene of E. Coli

Using a cloned fragment containing the lexA gene of E. coli, the entire nucleotide sequence of the lexA gene has been determined. The probable coding region of the lexA gene contains 606 nucleotide residues and encodes a single protein of 202 amino acids. The initiation site of in vitro transcription of the lexA messenger RNA has been determined by analysis of the 5' nucleotide sequence. Comparison of the DNA sequence of the promoter region of the lexA gene with that of the recA gene reveals the presence of sequences that are common to both. There is some similarity between the amino acid sequences of the lexA and the lambda repressor proteins.