Targets for the MalI repressor at the divergent Escherichia coli K-12 malX-malI promoters.
Random mutagenesis has been used to identify the target DNA sites for the MalI repressor at the divergent Escherichia coli K-12 malX-malI promoters. The malX promoter is repressed by MalI binding to a DNA site located from position -24 to position -9, upstream of the malX promoter transcript start. The malI promoter is repressed by MalI binding from position +3 to position +18, downstream of the malI transcript start. MalI binding at the malI promoter target is not required for repression of the malX promoter. Similarly, MalI binding at the malX promoter target is not required for repression of the malI. Although the malX and malI promoters are regulated by a single DNA site for cyclic AMP receptor protein, they function independently and each is repressed by MalI binding to a different independent operator site.
Lloyd
Georgina S
GS
School of Biosciences, University of Birmingham, Birmingham, UK.
Godfrey
Rita E
RE
Busby
Stephen J W
SJ
D001483:Base Sequence; D001665:Binding Sites; D004269:DNA, Bacterial / Q000378:metabolism*; D048168:Escherichia coli K12 / Q000235:genetics*; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D016296:Mutagenesis; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D012097:Repressor Proteins / Q000378:metabolism*
D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; C551037:MalX protein, E coli; D026901:Membrane Transport Proteins; D012097:Repressor Proteins; C060788:MalI protein, E coli