Cooperative interaction between Cra in the regulation of the cydAB operon of Escherichia coli .
Cra is known to bind to at least one nonconsensus binding site within the cydAB promoter .
For example , Cra binds to a nonconsensus site in the cydAB promoter region .
Cooperative interaction between Cra in the regulation of the cydAB operon of Escherichia coli .