Competitive and non-competitive enzyme inhibitors
The level of activity of an enzyme depends on the type of inhibitor acting on it.
Competitive inhibitors act by binding to the active site and preventing the substrate from binding.
The level of inhibition of the enzyme is dependent on the relative concentration of the competitive inhibitor to the substrate.
Through increasing the substrate concentration, it is possible to achieve the maximum reaction rate regardless of the presence of an inhibitor.
Non-competitive inhibitors bind elsewhere on the enzyme, but affect the shape of the active site, so the substrate can no longer bind.
When a non-competitive inhibitor is present the maximal reaction rate can never be achieved.