Laboratory Introduction
What is a protocol?
What is an enzyme?
Why do scientists �use protocols?
What are some examples �of enzymes in our lives?
Now let’s�practice�pipetting!
Enzyme/Substrate Reactions�
Using Mushroom Tyrosinase
What will happen?
Can it be prevented?
How?
Enzymes are Proteins
DNA → RNA → Protein
Organisms produce proteins, each having a different function…
Hormones
Hair and Nails
Structural Support
Enzymes
Muscle Contraction
Antibodies
Receptors, membrane channels
Nutrient Storage
All living things produce enzymes…�
Enzymes in our bodies have special jobs, too.
Digestion
DNA Replication
Metabolism
RNA Synthesis
Reproduction
Enzymes are the Construction�Workers of the Cell…�
Enzymes help
BUILD UP or BREAK DOWN
molecular structures
Enzymes are usually named with the suffix –ase added to the name of the substrate or reaction
Inhibitors�slow down�enzymes!
Paperclipase
Toothpickase
Enzymes in our daily lives:
PROTEASE
HYDROLASE
LACTASE
How do enzymes �speed up reactions?
The enzyme creates a favorable environment for the reaction.
Substrate
Enzyme
Substrate binds enzyme in active site.
Active site
Enzymes can be�used again and again!
CROSSING A STEEP
MOUNTAIN ROAD
By FOOT
Time: Days
BIKING
Time: One Day
DRIVING
Time: Hours
Weak Catalyst
Strong Catalyst
Normal Rate
They increase the rate of a chemical reaction�by lowering the energy requirement.
Enzymes “catalyze” reactions
Chemical�Reaction:
What happened?
Can it be prevented?
How?
a series of reactions involving the enzyme tyrosinase
Enzymatic Browning
Write one thing about enzymes that you can share with family or friends back in the classroom.
Remember to share �interesting facts about enzymes�with your classmates�during the lab!
��
Tyrosinase is produced in
Bacteria • Fungi • Plants • Animals
Tyrosinase & Albinism
Heat-Sensitive Tyrosinase
Mushroom Tyrosinase Lab�Protocol Overview
What’s a protocol again?
STEP 1: Extract Enzyme
Tyrosinase
STEP 2: Add Enzyme to Substrate
L-DOPA
Tyrosinase + L-DOPA = Dopachrome (pigment)
STEP 3: Measure Product
Enzyme
Substrate
Product
+
=
STEP 4: Graph Data Over Time
Amount
of product
Time
TEMPERATURE
pH
INHIBITOR
STEP 5: Test Enzyme Activity �Under Different Conditions
Summary of Protocol
- pH
- Temperature
- Inhibitor
What happened?�
What did you do in this lab?
Let’s review the steps!
STEP 1: Extract Enzyme
Tyrosinase
STEP 2: Add Enzyme to Substrate
L-DOPA
Tyrosinase + L-DOPA = Dopachrome (pigment)
STEP 3: Measure Product
Enzyme
Substrate
Product
+
=
STEP 4: Graph Data Over Time
Amount
of product
Time
STEP 5: Test Enzyme Activity �Under Different Conditions
TEMPERATURE
pH
INHIBITOR
Laboratory Follow-up
Obstacles during the lab
Solutions
Give details!�What was hard and why?
How can we make this lab�easier to understand?
Now it’s time �for your proposals!