Secondary Structure Flashcards
1
Q
How many residues are in a 360 degree rotation of an alpha helix?
A
3.6 residues
2
Q
What is the distance (in A) per 3.6 residues in an alpha helix?
A
5.4 A
3
Q
Which direction do R groups point in alpha helices?
A
Outward
4
Q
What two amino acids are not favored in alpha helices?
A
Glycine and Proline
5
Q
What is the bonding pattern of an alpha helix?
A
i+4
5
Q
What is the direction of the dipole moment in an alpha helix?
A
Positive to negative
6
Q
Which is more stable and why?
A
Antiparallel is more stable due to its colinear hydrogen bonding pattern.
6
Q
What are the two types of beta sheets?
A
Antiparallel and parallel
7
Q
What is the length (in A) of antiparallel bonding versus parallel bonding?
A
Antiparallel = 7A
Parallel= 6.5 A
8
Q
How many residues per A are in beta sheets?
A
2 residues
