Effects of temperature and pH on the enzymatic activity of a-amylaseIntroductionEnzymes are fundamental molecules within organisms. They are the biological catalysts of cells; increasing the rate of biochemical reactions, thereby ensuring that metabolic needs are met. These molecules are identified as globular proteins with a three-dimensional structure and are composed of one or more polypeptide chains. The polypeptide chain(s) within an enzyme are folded to form a specific active site. Each different structured active site catalyzes only a certain substrate suitable for it; this is called the lock and key model (Cooper, 2000). Enzymes achieve the highest reaction rate when they are in optimal conditions; these conditions include internal temperature and pH levels. When either of these conditions is not within the optimal range, the active sites of the enzyme can be denatured, thereby preventing the substrate from catalyzing and reducing the reaction rate (Berg, Tymoczko, Stryer et Stryer, 2002). The substrate catalyzed in this experiment is starch. Starch is a carbohydrate polysaccharide composed of numerous glucose molecules linked together in straight or branched chains using glycosidic bonds. The enzyme used in this experiment is a-amylase, simulating the starch-catalyzing salivary enzyme found in human saliva. The purpose of this experiment was to study how changes in pH and temperature affect the reaction rate of A-amylase enzymatic activity in a starch substrate. Reaction rates of α-amylase were observed using iodine. Throughout the experiment, the enzymatic reaction of the starch created a maltose product. Iodine reflects a blue color when in contact with a starch molecule and changes to a yellowish color in the middle of the paper. Fire and pH are just some of the conditions that manipulate enzyme activity. The enzyme concentration is directly correlated to the reaction rate up to the enzyme saturation point. Enzyme saturation is the point where the amount of enzymes (catalysis) and substrate are in balance, meaning that all enzymes in action and the maximum reaction rate have been reached. Enzyme concentration is just one of many other factors that can manipulate enzyme activity. Other factors include substrate concentration, inhibitors and viscosity effects. To better understand enzyme specificity, these factors need to be studied (Worthington Biochemical Corporation, 2015). Determining the effects of changes in pH and temperature on the enzymatic activity of α-amylase highlighted the specific nature of the enzymes and how they can only accomplish biochemical reactions under optimal conditions..