Enzymes are large biological molecules that are responsible for the thousands of metabolic processes that sustain life. • They are: • highly selective catalysts • greatly accelerating rate of metabolic reactions • greatly decrease the energy needed for a reaction • Mostly proteins, although some catalytic RNA molecules have been identified.
Structure • Enzymes are a 3-D structure that are highly complex. • Their structure is very important because they are specific to their substrates. • Enzyme origins: • Listen, will be important when we get to genetics.
Lock and Key Model • Enzyme, Substrate, Product
Amylase • Foods with Maltose • Sweet potatoes • Grain Cereals • Pears • McDonald Hotcakes • Catsup [Ketchup] • Tootsies rolls Lock and Key
Energy savers • Like all catalysts, enzymes work by lowering the activation energy • this dramatically increasing the rate of the reaction. • Most enzyme reaction rates are millions of times faster than those of comparable un-catalyzed reactions. • As with all catalysts, enzymes are not consumed by the reactions they catalyze • However, enzymes do differ from most other catalysts in that they are highly specific for their substrates. • Enzymes are known to catalyze about 4,000 biochemical reactions.
Enzyme activity can be affected by: • Other molecules • Inhibitors • Activators • Many drugs and poisons are enzyme inhibitors • Temperature • Pressure • Chemical environment (pH) • Concentration of substrate
Pressure • How could pressure effect enzymes? • Under pressure, dun dundundadi dun dum!
The experiment • What’s the enzyme? • What’s the substrate? • What’s the product?
The experiment • What’s the enzyme? • Catalase • What’s the substrate? • H2O2 • What’s the product? • H20 + O2
The Experiment • Basic Idea???? • How would you test pH’s affect on catalase? • How would you test temperatures effect on catalase? • How would you test for different amounts of substrate?
The Experiment • Test for pH • Keep the concentration of yeast the same but make a range of pH to test. • Test for temperature • Keep the concentration of yeast the same but make a range of temperatures. • Substrate concentration • Change the concentration of the substrate.