Patent ID: 7989611

Claim:
An expression control sequence which controls expression of a target gene linked downstream of the expression control sequence depending on an intracellular concentration of an amino acid, wherein in a bacterium which harbors a DNA construct comprising the expression control sequence, a promoter linked upstream of the expression control sequence and the target gene linked downstream of the expression control sequence, frequency of termination in the expression control sequence when transcription initiates from the promoter is decreased due to an increase in the intracellular concentration of an amino acid, whereby expression of the target gene increases, wherein said expression control sequence comprises a region coding for a leader peptide comprising said amino acid and a ρ independent terminator, wherein when translation of the leader peptide stops at codon of said amino acid in the course of the translation in case of starvation of said amino acid, a base paring structure of the ρ independent terminator is formed in a transcript of the expression control sequence, whereby the frequency of termination in the expression control sequence, of the transcription increases; wherein said expression control sequence comprises five segments which are from an attenuator of a tryptophan operon of Escherichia coli and an attenuator of a histidine operon of Escherichia coli when the five segments are numbered in order from an upstream side, the first and second segments, and a coding region for the leader peptide comprise the corresponding part of the attenuator of the tryptophan operon, the fourth and fifth segments comprise the corresponding part of the attenuator of the histidine operon, and the third segment comprises a combination of the corresponding parts of the attenuators of the tryptophan operon and the histidine operon; wherein the first segment overlaps with codon of the amino acid in the leader peptide; and wherein the sequence of each segment or a part thereof and the sequence of the adjacent segment or a part thereof constitute an inverted repeat sequence.