Enzyme Specificity (lock and key model) Mrs. Paparella October 28,2013

Enzyme names help to identify their corresponding substrate The carbohydrate molecule called sucrose is what is found in cane sugar. Sucrose is called a disaccharide because it is made of 2 sugars: glucose and fructose. It must be broken down by sucrase (an enzyme) in order to be small enough to be absorbed into the blood stream on the other side of the small intestine villi. What is the name of the substrate in this reaction? What suffix does the enzyme have?

Enzymes are Specific for the Substrates they act upon

Analysis of Enzyme-Substrate Action Notice in the previous slide that the active sites have a specific shape to fit the sucrose molecule edges. Why do you think this is called a hydrolysis reaction? What happens to the enzyme shape in the overall process? What would happen to the enzyme shape if we changed the pH or the temperature?

People born with congenital sucrase-isomaltase deficiency (CSID) can’t digest sucrose Sucraid® is a sucrase enzyme replacement therapy that catalyzes the hydrolysis of sucrose into glucose and fructose, thereby facilitating absorption from the small intestine into the bloodstream. [www.sucraid.net] .

Protease Works on Protein What are the building blocks of protein? Why do proteins need to be digested? What is the ending suffix of the enzyme? What kind of foods provide protein?

Starch is an example of a complex carbohydrate made of many simple sugar molecules What is the name of the enzyme in this reaction? What is the enzyme’s suffix? What is another name for a simple sugar? ( answer is not shown here) Polysaccharide is another name for a complex carbohydrate. What foods are polysaccharides?

Lipase acts on lipids Lipids are an organic molecule commonly known as fats/oils. Lipids are made up of fatty acids and glycerol. What foods are examples of lipids? What is the suffix of the enzyme?

Vocabulary to Review Enzyme Active site Lipase Carbohydrase Sucrase protease Substrate Hydrolysis Lipid Carbohydrate Sucrose protein