Proteins: Formation and loss of structure (folding, denaturation) and examples of correlations
between the form and function of a protein. Chapter 5, Campbell & Reese Second edition
Name ______________________________ Date _______________
20 common, stable amino acids make up proteins. Highlight the R group, variable region, in
each. Classify each as hydrophilic (HPL)—polar but uncharged, Hydrophobic (HPB), acidic
(negative), or basic (positive). Identify cysteine & methionine as disulfide bridge formers
(DSB). Remember: carboxyl groups ionize to become negatively charged; amino groups
become + charged UNLESS adjacent to a carbonyl group, CHSP have much lower
electronegativity than O or N, sulfahydryl groups form disulfide bridges. Fill in C & H atoms!
Movies to help with understanding protein structure, folding, shape, & function.
http://www.learner.org/courses/biology/units/proteo/images.html
click The Three-Dimensional Structure of a Protein
watch then define
primary structure of a protein
secondary structure
tertiary structure
quartenary structure
http://www.learner.org/vod/vod_window.html?pid=815
protein folding and functions
We’ve seen the first half of this movie in class (up to the start of tertiary structure)—watch if you need
more help with how proteins attain their functional shape
http://www.learner.org/vod/vod_window.html?pid=816
This movie explains the relationship between genetic code and protein structure and
function Watch first 12 minutes to better understand protein structure, then move to minute
21--22 to understand how mutation results in sickle cell anemia.
http://www.learner.org/resources/series187.html?pop=yes&pid=2036
This movie explains the relationship between a protein’s shape and its role. It
introduces the ways that scientists use info on proteins to control traits or develop
drugs/therapies.
Go to the Campbell place. Click on edition 7. Log in as: Mayfieldstudent1
Password scienceaccount2009
Go to chapter 5. Watch and interact with activity 5.4 protein function.
Type of proteins
function
function
Activity 5.4 Protein structure
Why are proteins called polypeptides?
What happens during formation of primary structure?
correlation between structure and
What part of primary structure is the same for all proteins?
What part of primary structure varies, and how is this variance controlled?
How many amino acids are commonly found in proteins?
What parts of a protein interact during protein folding? Why?
How is an alpha helix different from a Beta pleated sheet? Biologically, why are these
differences important (from Annenberg, learner.org world of chemistry proteins: structure
and function)
What parts of amino acids interact to allow formation of tertiary structure?
What three types of interactions are most important? Describe them.
How are tertiary and quarternary structures similar? Different?
http://www.wisc-online.com/objects/ViewObject.aspx?ID=AP13304
Summary of protein folding
http://www.wiley.com/college/boyer/0470003790/animations/protein_folding/protein_folding.ht
m
How do proteins develop their final shape?
1st:
2nd:
3rd:
4th:
This animation provides an overview of how proteins attain the correct shape, as well as of
how the shape can be distorted during denaturation.
http://highered.mcgrawhill.com/sites/0072943696/student_view0/chapter2/animation__protein_denaturation.html
1. Initially, why does heating a protein cause it to lose its shape? What kinds of bonds are
broken?
2. Why doesn’t the protein return to its native shape after heat is removed?
3. Why do denatured proteins , like cooked egg whites, clump up or coagulate?
http://www.sumanasinc.com/webcontent/animations/content/proteinstructure.html
Add any new understanding to your comments above. Take the postquiz!
http://intro.bio.umb.edu/111F98Lect/folding.html
4. What level of folding is being illustrated? _______________________ What event
seems to have a particularly strong impact?
_______________________________________________________________________
http://www.stolaf.edu/people/giannini/flashanimat/proteins/hydrophobic%20force.swf
what does this animation show?
Watch this animation to review:
http://www.johnkyrk.com/aminoacid.html
How do amino acids differ?
How is the difference between a peptide bond and the single covalent bond that links on R
groups important in protein folding?