Essay On Pepsin On Proteins

Introduction

An enzyme is a biological catalyst (Purchon 2012). Its most basic function is to speed up the rate of reaction (Enzymes (n.d.). Without the existence of enzymes in living organisms, the process of digestion would take weeks. The function of our muscles, nerves and bones will also decrease in efficiency (Purchon 2012). Therefore, the activities in living systems are dependent on and mostly controlled by enzymes. Similar to other catalysts, enzymes can be reused multiple times, however, their natural properties are easily taken away or altered by heat (Purchon 2012). In order for enzymes to maintain their qualities, they need to be in body temperature and a specific pH (Purchon 2012). The reason why enzymes are so sensitive to heat and pH is because they are protein molecules (Purchon

The protein that we used was albumin (egg white). The main objective was to model the activity of pepsin in the stomach by showing its actions on protein by simulating the effect with pepsin and egg whites. The experiment was carried out at a number of pH levels and temperatures to show that pepsin (and all other enzymes) have an optimal pH range and temperature in which they perform most effectively, in order to model the effect the changing pH has on the activity of the enzyme.

Enzymes have an optimal pH range and anything outside this range prevents its activity (Hendrickson 2010), therefore it was hypothesised that the lower the pH and the higher the temperature, the faster the rate of enzyme reaction (pepsin) activity. Pepsin has an optimal range of pH 2 (Pepsin 2012), which is highly acidic and is found in the stomach of the human body where it digests proteins. This means that any pH less acidic or more basic than this level will not allow the reaction to occur, as these are not the optimal conditions for the activity of the