Strong acids contain many H+ ions. Strong bases contain many OH- ions. These ions disrupt certain bonds within enzymes called hydrogen bonds, ionic bonds, hydrophobic interactions or hydrophilic interactions. Disrupting these bonds causes the active site of the enzyme to change shape, altering the enzymes tertiary structure. This means that substrates can no longer fit in to the enzymes active site because they are no longer complementary in shape, which stops the enzyme performing its funtion
