substances which bind to enzymes and slow down their ROR, so less product is made (many drugs and poisons work this way)
How do enzyme inhibitors reduce the ROR?
they can prevent a substrate binding to the active site of an enzyme - this means no/reduced E-S complexes formed
What are the 2 types of enzyme inhibitors?
competitive and non-competitive
What are competitive inhibitors?
they have a similar structure to the substrate and they compete for the active site. This means less E-S complexes are formed so less product is made
What do the competitive inhibitors do?
they bind temporarily to the active site so it is reversible. Effect can be overcome by increased substrate concentration
What non-competitive inhibitors do?
they attach to a binding site which is not the active site -doesn't compete with the substrate for the active site
What issue does the non-competitive inhibitor cause?
it causes distortion of the shape of the active site and changes its shape. This means the substrate can no longer bind to the active site so less E-S complexes are formed so less product is made. It also binds permanently so it is irreversible
When are the competitive inhibitors most likely to bind to the active site?
when there's low concentrations of substrate. This means fewer E-S complexes are formed, lowering ROR
How can you stop competitive inhibitors?
increase substrate concentration. This decreases the effect of the competitive inhibitor so ROR increases
What happens when there's no non-competitive inhibitor?
the maximum reaction rate is achieved at high substrate concentration
What happens when there's a non-competitive inhibitor?
maximum reaction rate is never achieved. The effect of the inhibitor can't be overcome by increasing the substrate concentration. The active site remains changed so no E-S complexes as the substrate can't bind to the active site