Enzyme inhibition

Explain how temperature above the optimum temperature can denature an enzyme

The thermal energy breaks the hydrogen bonds holding the secondary and tertiary structure of the enzyme together so the enzyme and its active site lose their shape so the substrate can no longer bind

Competitive inhibitors

Occupy the active site of an enzyme

Non competitive inhibitors

Attach to the enzyme at a site other than the active site

Lock and key model

Suggests that the enzyme is a lock and the substrate is like a key that fits into it due tot heir complementary in shape

The enzymes active site is a fixed shape and that due to random collisions the substrate can collide and attach to the enzyme- this forms an enzyme substrate collision

Once the enzyme substrate complex has formed the charged groups within the active site are thought to distort the substrate and therefore lower the activation energy. The products are then released and the enzyme active site is empty and ready to be reused

Induced fit model

Model suggests that the enzyme is like a glove and the substrate is like your hand- the empty glove is not exactly complementary in shape to your hand , but when your hand enters it enables the glove to mould around tour hand to become completely complementary

Enzyme active site is induced, or slightly changed shape to mould around the substrate-

when the enzyme substrate complex occurs due to the enzyme moulding around the substrate it puts strain on the bonds and therefore lowers the activation energy

The products are then removed and the enzyme active site returns to its original shape

The induced fit model is the accepted model for how enzymes function