BetterScholar BetterScholar
Title Claps Level Year L/Y
Unusual organization, complexity and redundancy at the Escherichia coli hcp-hcr operon promoter.
David L. Chismon, D. Browning, Gregory K. Farrant, S. Busby
Expression from the Escherichia coli hcp-hcr operon promoter is optimally induced during anaerobic conditions in the presence of nitrite. This expression depends on transcription activation by FNR (fumarate and nitrate reduction regulator), which bi…
Expression from the Escherichia coli hcp-hcr operon promoter is optimally induced during anaerobic conditions in the presence of nitrite. This expression depends on transcription activation by FNR (fumarate and nitrate reduction regulator), which binds to a target centred at position -72.5 upstream of the transcript start site. Mutational analysis was exploited to identify the corresponding -10 and -35 hexamer elements. A DNA site for NarL and NarP, located at position -104.5, plays only a minor role, whereas NsrR binding to a DNA target centred at position +6 plays a major role in induction of the hcp-hcr operon promoter. Electrophoretic mobility-shift assays show that NsrR binds to this target. The consequences of this for the kinetics of induction of the hcp-hcr operon are discussed.
Published in Biochemical Journal
0
4 2010