Enzyme Inhibitors 1A-6

Enzyme activity can be prevented by inhibitors. The two types of inhibitors are competitive and non- competitive.

A competitive inhibitor bears a similar shape to that of the substrate, therefore it can compete with the substrate t bind to the active site of the enzyme. If an inhibitor binds to an enzymes active site before the substrate does, the substrate cannot bind to that particular active site as it has been blocked. If there is a high concentration of inhibitors, the inhibitors will take up almost all of the active sites, leaving non for the substrates. However, if there is a high amount of substrate then the chances of the substrate binding to an active site before the inhibitor does are increased. 

Non-competitive inhibitors bind to the enzyme away from the active site. This changes the shape of the active site and therefore substrates can no longer fit. Unlike w

ith competitive inhibitors, increasing the concentration of substrates will not make much of a difference as they are not both competing for the active site.

The graph shows how increasing the amount of subtrate concentration would affect the rate of reaction for both types of inhibitors.