How is the tertiary structure of an enzyme important to its function?

The tertiary structure involves four types of bonds being made between secondary alpha helices or beta pleated sheets. These are disulfide bridges, hydrophilic/hydrophobic bonds, ionic bonds and hydrogen bonds. These bonds determine the enzyme's overall 3D shape, including that of the active site. For the enzyme to work, according to the induced fit model, the shape of the active site must be exactly complementary to the shape of the substrate, in order to form an enzyme-substrate complex. If the tertiary structure is altered, an enzyme-substrate complex cannot be formed, and the enzyme is said to be denatured.