How do bacteria avoid wasteful production of unnecessary proteins when their genes are always on? The answer lies in regulating the operon. As trp levels increase, trp binds to trpR, causing a ...

The lac operon genes are expressed to digest the available lactose until this sugar is depleted, at which point the operon shuts down. However, the lac operon was far from solved. “ [It] turned out ...

When glucose and lactose are both available, allolactose releases LacI from the operator, allowing binding of the RNA polymerase. However, in the absence of cAMP to permit CRP binding, the polymerase ...

Carbon catabolite repression (CCR) is a global regulatory mechanism that inhibits the expression and activities of functions for the use of secondary carbon sources when a preferred carbon source is ...