BCH 351 EXAM 2 (DR. KUO) UPDATED ACTUAL
QUESTIONS AND CORRECT ANSWERS
Question:
1. Describe globular proteins
Answer:
1.) Spherical 3-D structure (more compact)
2.) Incorporate several types of secondary structures
3.) Charged/ polar amino acids in the interior
4.) Hydrophobic amino acids in the interior
5.) soluble proteins
Question:
2. What is a ligand?
Answer:
A molecule that binds to a protein, typically a small molecule
Question:
3. What is a binding site?
Answer:
A region in a protein where a ligand binds
Question:
4. How do ligands bind?
Answer:
Noncovalent interactions that dictate protein structure (allows interaction to
be transient)
Question:
5. What does myoglobin do?
Answer:
Stores/ delivers O₂ in muscles
Question:
6. What does hemoglobin do?
Answer:
Transports O₂ in the blood
, Question:
7. What do all members of the globin family have in
common?
Answer:
All bind to O₂ although not all transport O₂
Question:
8. What are prosthetic groups?
Answer:
Tightly bound organic coenzymes which are also called heme
Question:
9. What are prosthetic groups composed of?
Answer:
1.) porphyrin ring
2.) Fe²⁺
Question:
10. Explain the structure of pyrrole rings
Answer:
1.) 4 pyrrole rings are linked and the N of each binds to Fe²⁺
2.) planar structure
3.) binds in a hydrophobic pocket of the protein
Question:
11. How do pyrrole rings bind to O2?
Answer:
1.) Fe forms a complex with 6 atoms (4 w/ N in the heme, 1 w/ N of His
prox., 1 w/ O of O₂)
2.) Other O of O₂ forms H-bond with N of His distal
3.) O₂ is bounded reversibly so it can bind and then dissociate
Question:
12. What is CO poisoning?
Answer:
When CO binds to heme irreversibly
Question:
13. What does O2 binding to the heme group cause?
Answer:
Conformation changes; when O binds to Fe, it causes the heme to become
planar and the entire helix shifts
QUESTIONS AND CORRECT ANSWERS
Question:
1. Describe globular proteins
Answer:
1.) Spherical 3-D structure (more compact)
2.) Incorporate several types of secondary structures
3.) Charged/ polar amino acids in the interior
4.) Hydrophobic amino acids in the interior
5.) soluble proteins
Question:
2. What is a ligand?
Answer:
A molecule that binds to a protein, typically a small molecule
Question:
3. What is a binding site?
Answer:
A region in a protein where a ligand binds
Question:
4. How do ligands bind?
Answer:
Noncovalent interactions that dictate protein structure (allows interaction to
be transient)
Question:
5. What does myoglobin do?
Answer:
Stores/ delivers O₂ in muscles
Question:
6. What does hemoglobin do?
Answer:
Transports O₂ in the blood
, Question:
7. What do all members of the globin family have in
common?
Answer:
All bind to O₂ although not all transport O₂
Question:
8. What are prosthetic groups?
Answer:
Tightly bound organic coenzymes which are also called heme
Question:
9. What are prosthetic groups composed of?
Answer:
1.) porphyrin ring
2.) Fe²⁺
Question:
10. Explain the structure of pyrrole rings
Answer:
1.) 4 pyrrole rings are linked and the N of each binds to Fe²⁺
2.) planar structure
3.) binds in a hydrophobic pocket of the protein
Question:
11. How do pyrrole rings bind to O2?
Answer:
1.) Fe forms a complex with 6 atoms (4 w/ N in the heme, 1 w/ N of His
prox., 1 w/ O of O₂)
2.) Other O of O₂ forms H-bond with N of His distal
3.) O₂ is bounded reversibly so it can bind and then dissociate
Question:
12. What is CO poisoning?
Answer:
When CO binds to heme irreversibly
Question:
13. What does O2 binding to the heme group cause?
Answer:
Conformation changes; when O binds to Fe, it causes the heme to become
planar and the entire helix shifts
