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Unformatted text preview: trp repressor must first bind to a molecule of tryptophan before it can bind effectively to the trp operator. The trpR gene encodes the repressor. trpO is the operator. trpA encodes the enzyme tryptophan synthetase. A trpR-repressor cannot bind tryptophan. A trpO-operator cannot be bound by the repressor. And the enzyme encoded by trpA-mutant is completely inactive. Do you expect to find active tryptophan synthesetase in each of the following strains when the cells are grown in the presence of tryptophan and in its absence? (+) indicates wild type. R + O + A + R-O + A + / R + O + A-R + O- A + / R + O + A-R + O- A + / R + O- A-R-O + A + s fi n d tr y...
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- Spring '08
- trp operon