In a feedback-regulated enzymatic pathway, the most likely true statement is that the final product of the pathway binds to an earlier enzyme in the pathway and deactivates it or inhibits its activity. This negative feedback mechanism prevents overproduction of the final product by shutting down or reducing activity in earlier steps of the pathway. Key points:
- Feedback regulation occurs when a product of the enzymatic reaction binds to an allosteric site on an enzyme, affecting its catalytic activity.
- Negative feedback inhibition typically involves the final product of a pathway binding to and inhibiting an earlier enzyme in the pathway.
- This feedback inhibition reduces the activity of earlier enzymes to stop or slow the pathway, conserving resources and preventing waste.
- Usually, the final product binds to the first or an early enzyme in the pathway, such as enzyme 1 (E1), to exert inhibitory control.
Thus, the statement "P4 (final product) binds to E1 (the first enzyme) and deactivates it" is most likely to be true in the case of a feedback-regulated enzymatic pathway.
