Chapter 7 Notes

Question 1

Which structure is identical to the heme structure?

Answer 1

myoglobin

Question 2

__ supplies four nitrogens to bind iron.

Answer 2

Heme

Question 3

What role does Histidine play in heme?

Answer 3

proximal histidine directly bonds to heme; distal histidine is very close in area but doesn’t directly bind

Question 4

Difference in oxygen bonding between myoglobin and hemoglobin?

Answer 4

Hemoglobin: 70%
Myoglobin: 2%

Question 5

What are the P50 values of hemoglobin and myoglobin? What is P50?

Answer 5

P50 = half saturation
Hemoglobin: 26 torr
Myoglobin: 2 torr

Question 6

How do you find the fractional saturation of myoglobin/hemoglobin?

Answer 6

y = (how many sites bonded) / (total # of sites)

Question 7

Most allosteric proteins will have a __ curve.

Answer 7

sigmoidal

Question 8

What is the key way that enzymes are regulated?

Answer 8

allosteric regulation

Question 9

What is the best example for allosteric regulation?

Answer 9

Hemoglobin (the oxygen carrier in blood)