First and Last Name ______________________________ SID __ __ __-__ __ __-__ __ __
R. Lannan _________ ___ _ CHEM 153A___________ __Mon, Mar 18, 2024
3:00 pm
Final Exam
Instructions (please read carefully)
1. The exam consists of 10 questions (12 pages total)
2. Pen is preferred but if you use a pencil you MUST write dark
3. Take the time to write your name and ID on EVERY page
4. Please bubble in your answers – light checkmarks can’t be read by the AI
5. Do NOT write on the back of any page of the exam as we don’t scan the backs of pages.
If you cannot fit your answer in the provided space, write your answer on Page 10.
6. If you are in need of assistance, please raise your hand quietly. Do your best!
________________________________________________________________________
1
, First and Last Name ______________________________ SID __ __ __-__ __ __-__ __ __
1. Amino acids and protein structure (12 pts)
a. Do the following using the α-helix model provided:
iiif
i. (2 pts) Notate the orientation of the N and C
termini for this α-helix.
N C
C N
ii. (2 pts) Notate the orientation of the inherent
dipole moment of this α-helix ivf
- +
+ -
iii. (1 pt) The bond labeled ‘iii’ represents a…
φ angle Ѱ angle
iv. (1 pt) The bond labeled ‘iv’ represents a…
φ angle Ѱ angle
b. (2 pts) Consider the polypeptide chain within a
right-handed α-helix. Given the Ramachandran
plot provided, what is a possible φ and Ѱ angle for
an amino acid residue within this structure?
φ = 60° φ = -90° φ = -90° φ = 60°
Ѱ = -120° Ѱ = -20° Ѱ = 150° Ѱ = 45°
c. (2 pts) Your lab is working on developing self-assembling macromolecular
structures. For a proof-of-principle, you’ve developed simple β-sheet
peptides that will spontaneously stick together (pair-wise) in an aqueous
environment (see below diagram). What is a reasonable primary sequence
for a strand of this β-sheet? f
K-S-L-A-E-N-F-I-K-D
I-E-F-D-L-K-L-S-F-N
L-I-E-K-A-V-N-S-A-L
d. (2 pts) A solution of aspartic acid is set to a pH of 9. Which of the following
species predominates in solution?
2
R. Lannan _________ ___ _ CHEM 153A___________ __Mon, Mar 18, 2024
3:00 pm
Final Exam
Instructions (please read carefully)
1. The exam consists of 10 questions (12 pages total)
2. Pen is preferred but if you use a pencil you MUST write dark
3. Take the time to write your name and ID on EVERY page
4. Please bubble in your answers – light checkmarks can’t be read by the AI
5. Do NOT write on the back of any page of the exam as we don’t scan the backs of pages.
If you cannot fit your answer in the provided space, write your answer on Page 10.
6. If you are in need of assistance, please raise your hand quietly. Do your best!
________________________________________________________________________
1
, First and Last Name ______________________________ SID __ __ __-__ __ __-__ __ __
1. Amino acids and protein structure (12 pts)
a. Do the following using the α-helix model provided:
iiif
i. (2 pts) Notate the orientation of the N and C
termini for this α-helix.
N C
C N
ii. (2 pts) Notate the orientation of the inherent
dipole moment of this α-helix ivf
- +
+ -
iii. (1 pt) The bond labeled ‘iii’ represents a…
φ angle Ѱ angle
iv. (1 pt) The bond labeled ‘iv’ represents a…
φ angle Ѱ angle
b. (2 pts) Consider the polypeptide chain within a
right-handed α-helix. Given the Ramachandran
plot provided, what is a possible φ and Ѱ angle for
an amino acid residue within this structure?
φ = 60° φ = -90° φ = -90° φ = 60°
Ѱ = -120° Ѱ = -20° Ѱ = 150° Ѱ = 45°
c. (2 pts) Your lab is working on developing self-assembling macromolecular
structures. For a proof-of-principle, you’ve developed simple β-sheet
peptides that will spontaneously stick together (pair-wise) in an aqueous
environment (see below diagram). What is a reasonable primary sequence
for a strand of this β-sheet? f
K-S-L-A-E-N-F-I-K-D
I-E-F-D-L-K-L-S-F-N
L-I-E-K-A-V-N-S-A-L
d. (2 pts) A solution of aspartic acid is set to a pH of 9. Which of the following
species predominates in solution?
2
