Ch. 2 Review

Question 1

pKa

Answer 1

NH3+ = 9
OH- = 2
SH = 8

Question 2

Gain e-

Answer 2

Reduction

Question 3

Lose e-

Answer 3

Oxidation

Question 4

Phi

Answer 4

C-N bond

Question 5

Psi

Answer 5

C-C bond

Question 6

Ramachandran plot

Answer 6

Show values of psi and phi + locations and angles

Question 7

Secondary structure of a protein

Answer 7

Alpha helix

Question 8

Characteristics of alpha helix

Answer 8

• 5.4 A•
• Hydrogen bonds
• Every 4th AA residue forms H+ bonds

Question 9

Characteristics of Beta-sheet

Answer 9

-anti + parallel strands

Anti: strands run in opposite directions, bonding is shorter and more stable

Parallel: adjacent strands run in same direction

7A•

Question 10

Characteristics of turns and loops

Answer 10

Bond/turn= same

Turns: smaller length, beta is most common

Loops: no H+ between length, no particular character, relatively long, random coil

Question 11

What is a tertiary structure

Answer 11

3D structure

Question 12

Fibrous proteins of:

1) alpha-keratin
2) collagen

Answer 12

1) every 7 AA Is a leucine. There is also a cysteine reach

2) every 3 AA there is a glycine. There is also a proline reach + stiff turn and hydroxyl proline

Question 13

What are globular proteins? Give example.

Answer 13

• Water-soluble proteins
• non-polar cores (hydrophilic outside + hydrophobic inside)

Ex.) myoglobin