Introduction to Enzymes
Enzymes have the added property of providing for selectivity of reactants and products of the chemical reaction they catalyze. The enzyme has provided for both reactant (called the substrate in enzyme terminology) and product specificity. Another thing that the enzyme accomplished was that it allowed the reaction to proceed at neutral pH as compared with low pH for the nonenzymatic reaction. The enzyme also binds a molecule of acetic acid (as a second substrate) such that it is located and oriented just right to react with the 3-hydroxyl of the d-glucose to produce 3-acetyl-d-glucose. By providing favorable micro-environments, and proper orientation of substrates in these micro-environments, enzymes accomplish a lowering of the activation energy of the reaction. Enzymes are capable of very large increases in chemical reaction rates. There are many ways for measuring enzyme reaction rates. Enzymes cannot, under most circumstances, be directly measured by their abilities to bind their substrates as we do with receptor-ligand interactions.