Why does enzyme activity increase with temperature

The optimum temperature for most enzymes is about There are also enzymes that work well at lower and higher temperatures. For example, Arctic animals have enzymes adapted to lower optimal temperatures; animals in desert climates have enzymes adapted to higher temperatures.

However, enzymes are still proteins, and like all proteins, they begin to break down at temperatures above degrees Fahrenheit. Therefore, the range of enzyme activity is determined by the temperature at which the enzyme begins to activate and the temperature at which the protein begins to decompose. Enzyme Kinetics Enzymology Assays. To discuss more service details, please contact us by calling , or e-mailing us at info creative-enzymes. Website Search Exact Search Search.

Plant Extracts. Mushroom Extracts. Animal Extracts. Fruit Powder. Vegetable Powder. Vegetarian Protein. We preserve our food by refrigerating or freezing it, which slows enzyme activity. Because most enzymes are proteins, they are sensitive to changes in the hydrogen ion concentration or pH.

Ionizable side groups located in the active site must have a certain charge for the enzyme to bind its substrate. An enzyme exhibits maximum activity over the narrow pH range in which a molecule exists in its properly charged form. With the notable exception of gastric juice the fluids secreted in the stomach , most body fluids have pH values between 6 and 8.

Not surprisingly, most enzymes exhibit optimal activity in this pH range. However, a few enzymes have optimum pH values outside this range. For example, the optimum pH for pepsin, an enzyme that is active in the stomach, is 2. Initially, an increase in substrate concentration leads to an increase in the rate of an enzyme-catalyzed reaction.

As the enzyme molecules become saturated with substrate, this increase in reaction rate levels off. The rate of an enzyme-catalyzed reaction increases with an increase in the concentration of an enzyme. At low temperatures, an increase in temperature increases the rate of an enzyme-catalyzed reaction. At higher temperatures, the protein is denatured, and the rate of the reaction dramatically decreases.

An enzyme has an optimum pH range in which it exhibits maximum activity. In non-enzyme-catalyzed reactions, the reaction rate increases as the concentration of reactant is increased. In an enzyme-catalyzed reaction, the reaction rate initially increases as the substrate concentration is increased but then begins to level off, so that the increase in reaction rate becomes less and less as the substrate concentration increases.

As with many chemical reactions, the rate of an enzyme-catalysed reaction increases as the temperature increases. However, at high temperatures the rate decreases again because the enzyme becomes denatured and can no longer function.

This is shown in the graph below. As the temperature increases so does the rate of enzyme activity. An optimum activity is reached at the enzyme's optimum temperature. A continued increase in temperature results in a sharp decrease in activity as the enzyme's active site changes shape.