The existence of repressors, as pre-existing chemicals tailored to both products (inducers) and their production mechanism (operons), are fascinating -- it seems that a molecule would be special if such an intricate chemical mechanism evolved to regulate it. Other than lactose, the example I'm familiar with, for which types of molecules do repressors exist?
closed as not a real question by Mad Scientist♦ Oct 30 '12 at 13:31
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