Proteolytic Enzymes in Detergents: Evidence of Their Presence through Activity Measurements Based on Electrophoresis

O well-established application of biotechnology is the use of enzymes in detergents. Enzymes are proteins that act as biochemical catalysts and that increase the rate of specific reactions by several orders of magnitude (usually g10). Cells cannot function without enzymes, but under controlled conditions, enzymes can work outside of the cell. This discovery led to the development of a growing number of industrial applications of enzymes. One of the main applications of enzymes is their use in detergents (especially laundry and dishwashing detergents) to help in cleaning. Enzymes (especially proteolytic enzymes) are found in products ranging from household laundry and dishwashing detergents to products for contact lens and denture cleaning. However, household laundry is the biggest market. A measure of success of a laboratory exercise, both in terms of effective learning and motivation, is student engagement. A problembased approach is one way to achieve this, especially if the laboratory relates to familiar industrial or home activities. Thus, a household detergent was chosen to study one of the applications of the catalytic power of enzymes. A number of basic concepts can be examined: the amino acid composition of proteins, the influence of factors such as pH or temperature on enzyme activity, the effect of denaturation, enzyme inhibition, and so forth. Students also become acquainted with polyacrylamide gel electrophoresis, which is used to see the products of the proteolytic enzyme activity on a protein substrate. This exercise has received positive response from students over the four years it has been performed.