Enzymes The protein catalyst of life

Enzyme Vocabulary Enzymes end in –ase Enzymes end in –ase –Maltase binds to maltose –Lactase binds to lactose –Lipase breaks down fat –Amylase is found in saliva Catalyst: Catalyst: –Substance that affects the rate of a chemical reaction WITHOUT BEING ALTERED –Because it is not altered, can do same thing over, and, over, and, over, and over……. –Enzymes are ORGANIC OR BIOLOGICAL CATALYSTS

Enzymes are little Energizer Bunnies!

Enzyme Vocabulary con’t…. Substrate: Substrate: –The substance upon which the enzyme reacts Active site: Active site: –Site where enzyme binds to substrate Denature: Denature: –When enzyme’s shape is altered due to: 1.high temp 2.Wrong (pH) acids or bases

You Tube clip: How enzymes work 75us18&feature=related 75us18&feature=related 75us18&feature=related 75us18&feature=related

Importance of Enzyme Shape Enzymes have specific shapes Enzymes have specific shapes This means enzymes are specific to their substrate This means enzymes are specific to their substrate They will only attach to substrate that “fits” their shape They will only attach to substrate that “fits” their shape If shape of enzyme is denatured, will it be able to bind to its substrate? If shape of enzyme is denatured, will it be able to bind to its substrate? –NO ! Two things can cause denaturing: Two things can cause denaturing: 1.Temperature 2.pH

Enzyme-Substrate Complex Formed when enzyme binds to substrate Formed when enzyme binds to substrate –Very specific Lock and Key Model: Lock and Key Model: –Enzyme-substrate complex often compared to a lock and key –Active site on enzyme can only “FIT” or bind to a specific substrate specific substrate  Example: Amylase will bind to starch, but not cellulose which is also made of just glucose DEMO

Enzyme-substrate Complex

The Enzyme Jingle! SUNG TO “JINGLE BELLS”! Shape, Shape, Shape Enzymes have a shape If active site is denatured It won’t bind su-ubstra-ate Shape, shape, shape Enzymes have a shape Wrong pH or temperature Will affect its shape

What affects Enzyme Reaction Rates? Remember, enzymes speed up reactions Remember, enzymes speed up reactions What can affect the rate at which enzymes perform? What can affect the rate at which enzymes perform? 1.It’s shape!  Denaturing affects rate 2.The amount of enzyme and substrate!

Enzyme shape and reaction rate: Temperature Enzymes have a specific temperature range at which they work best Enzymes have a specific temperature range at which they work best –EX. Human enzymes work best at 37°C Temps not in the optimal range will cause enzymes to denature Temps not in the optimal range will cause enzymes to denature Shape is altered, so reaction rates are SLOWED or stopped altogether Shape is altered, so reaction rates are SLOWED or stopped altogether Reaction rates will DROP dramatically depending on how much denaturing of enzyme Reaction rates will DROP dramatically depending on how much denaturing of enzyme DEMO

Temperature vs. Reaction Rate

Enzyme shape and reaction rate: pH Enzymes have a specific pH range at which they work best Enzymes have a specific pH range at which they work best –EX. Most enzymes work best at pH 7 –Where in the body would enzymes be optimal at a low (acidic) pH? Why?  In stomach. This is because stomach acid has a low pH pH not in the optimal range will cause enzymes to denature pH not in the optimal range will cause enzymes to denature Shape is altered, so reaction rates are SLOWED or stopped altogether Shape is altered, so reaction rates are SLOWED or stopped altogether Reaction rates will DROP dramatically depending on how much denaturing of enzyme Reaction rates will DROP dramatically depending on how much denaturing of enzyme

pH vs. Reaction Rate

Enzyme amount and reaction rate Enzyme rate also depends on the amount enzyme and substrate Enzyme rate also depends on the amount enzyme and substrate –Little enzyme, lots o’ substrate:  Slower rates  How can we speed up the rate? –Add more enzyme until max. rate achieved.

Substrate Concentration vs. Reaction Rate

CAPTAIN ENZYME! He is a biological superhero, roaming our bodies for health and justice. 1. Create a quote that captain enzyme would say using the vocab we have learned this week. 2. Make sure you are using the terms properly! 3. Grade will be based on: 1.Use of vocab 2.Creativity 3.Superhero Impersonation