Enzyme

Enzymes generally have an optimum pH range in which they are most active. The pH of the environment will effect the ionization state of catalytic groups at the active site and the ionization of the substrate. Electrostatic interactions are therefore controlled by pH. pH may also control the conformation of the enzyme through ionizable amino acids which are located distant from the active site, but are nevertheless critical for the three-dimensional shape of the macromolecule.

Figure 5. Illustration by Hans & Cassidy. Courtesy of Gale Group.

Figure 6. Illustration by Hans & Cassidy. Courtesy of Gale Group.