10/20/14 have your hw out current science quiz 2.1-2.2 back review the ws (1 st period we’ll fold...
TRANSCRIPT
10/20/14• Have your HW out• Current science• Quiz 2.1-2.2 back• Review the ws (1st period we’ll fold too)• Real world protein example: sickle cell• Protein Intro
• Protein pennies
• Enzyme Lab• Prelab
• HW: individual lab information
Change of Shape is Critical• In lungs conditions cause hemoglobin to bind oxygen
•Near muscles conditions cause hemoglobin to release oxygen
Just 1 Amino Acid Difference
Glutamic Acid Valine
Correct a.a is hydrophyllic
Incorrect a.a is hydrophobic!
• http://www.youtube.com/watch?v=1fN7rOwDyMQ• 4:50• http://www.dnalc.org/resources/3d/17-sickle-cell.html• 0:58
Enzymes Are Specific
•Have complementary structures allowing them to bond with only certain substrates
The Penny-Picker Enzyme
• Function of Penny-Picker:• Pick up pennies and flip them over• The pennies represent a toxic byproduct of cellular
processes that must be converted to a safer form
• Active site: • Specific to ONE substrate. What’s the substrate?
• Pennies
• Only holds ONE penny at a time
Data Table• On your whiteboard make the following table:
After 10s After 20s After 30s After 40s
Trial 1
Trial 2
Trial 3
Trial 4
Trial 5
Procedure - Trial 1: Baseline• Spread out pennies on table HEADS side up
• Without looking (enzymes don’t have eyes!) grab pennies and flip them over, putting them in the corner of your table
• One person flips pennies for FOUR 10-second intervals without looking; one person times and counts
• Record data on your whiteboard.
• DO NOT REPLACE THE PENNIES BETWEEN TIME INTERVALS
Procedure - Trial 2: Denaturation
• Spread out all pennies on table HEADS side up
• Repeat procedure for flipping pennies in four 10-second intervals
• THIS TIME: • Hand used to flip pennies gets taped around all four
fingers (partial denaturation)
• Record data on white board
• Come up with a definition of denaturation.
Procedure - Trial 3: Coenzyme
• Again spread out pennies on table HEADS side up
• Repeat procedure for flipping pennies in four 10-second intervals
• THIS TIME: • Enzyme has the help of a teammate, representing
a coenzyme
• Coenzyme picks up pennies and hands them to enzyme for flipping & moving
• Record data on white board
Co-Enzymes
*No Need to take notes or memorize for quiz – this is just to exemplify importance of enzymes
Procedure - Trial 4: Competitive Inhibitors• Spread out pennies on table with approximately 50/50 mix of
HEADS and TAILS up
• TAILS pennies represent competitive inhibitors. Molecules that have a similar shape and bind to the active site, but cannot be broken down.
• Repeat procedure for flipping pennies in four 10-second intervals
• THIS TIME:
• If your partner picks up a HEADS penny they move it to the edge of the table & flip it to tails and you count it
• If your partner picks up a TAILS penny you must stop them and tell them to put it back down
• Record data on whiteboard
Procedure – Trial 5: Non-Competitive Inhibition
• Spread the pennies out as before• Make your hand into a fist• Tape it closed
• This represents an inhibitor that binds to the enzyme and permanently alters its shape
• Try to pick up pennies for each of the 4 intervals
• Fail to pick up pennies and die
Non-Competitive Inhibitors and Venoms
*No Need to take notes or memorize for quiz – this is just to exemplify importance of enzymes
• Where do genes come from?• The connection to venom!• https://www.youtube.com/watch?v=z9HIYjRRaDE