Day 8

Question 1

can be found in almost any cellular proces

Answer 1

protein ligand complexes

Question 2

mediates the uptake and storage of cargo, such as oxygen uptake in myoglobin and hemoglobin

Answer 2

protein ligand interaction

Question 3

provides a measure of the affinity for the ligand L for the protein

Answer 3

association constant (Ka)

Question 4

higher Ka means what for affinity

Answer 4

higher affinity

Question 5

reciprocal of Ka

Answer 5

dissociation constant

Question 6

lower Kd means what for affinity

Answer 6

higher affinity

Question 7

when ligand conc = Kd, how much of the ligand binding sites are occupied

Answer 7

1/2

Question 8

which is easier to measure, partial pressure of O2 or O2 conc

Answer 8

partial pressure

Question 9

partial pressure of oxygen at which half of the binding sites are occupied in the dissociation curve of O2 binding to myoglobin

Answer 9

P50

Question 10

tetrameric protein with 4 heme groups

Answer 10

hemoglobin

Question 11

how many heme groups in 1 hemoglobin

Answer 11

4

Question 12

two conformations of hemoglobin

Answer 12

r state and t state

Question 13

hemoglobin has a higher affinity for O2, which conformation

Answer 13

r state

Question 14

more stable when O2 is absent

Answer 14

t state

Question 15

lower affinity for O2, which conformation of hemoglobin

Answer 15

t state

Question 16

predominant conformation of deoxyhemoglobin

Answer 16

t state

Question 17

what kind of binding curve does hemoglobin have for oxygen

Answer 17

hybrid sigmoid curve

Question 18

binding of a ligand to one site affects the binding properties of another site on the same protein

Answer 18

allosteric protein

Question 19

binding of a ligand to one site affects the binding properties of another site on the same protein, what kind of binding is this

Answer 19

cooperative binding

Question 20

how many models are there for cooperative binding

Answer 20

2

Question 21

all subunits in same conformation, what model of cooperative binding

Answer 21

MWC model=concerted model

Question 22

ligand binds more tightly to the R state, which model of cooperative binding

Answer 22

MWC model=concerted model

Question 23

each subunit can be in either conformation, which model

Answer 23

sequential model

Question 24

equilibrium is altered as additional ligands are bound, progressively favoring the R state, which model

Answer 24

sequential

Question 25

what two products does hemoglobin carry

Answer 25

H+ and CO2

Question 26

what isn’t soluble in aqueous solutions

Answer 26

CO2

Question 27

catalyzes the hydration of CO2 to bicarbonate

Answer 27

carbonic anhydrase

Question 28

what binding to hemoglobin is inversely related to binding of O2

Answer 28

CO2

Question 29

describes the effect of pH and [CO2] on the binding and release of O2 by hemoglobin

Answer 29

Bohr effect

Question 30

structural effects of H+ and CO2 binding to hemoglobin favor what state

Answer 30

t state

Question 31

what regulates oxygen binding to hemoglobin

Answer 31

2,3 bisphosphoglycerate

Question 32

single amino acid substitution, beta chains produces a hydrophobic patch

Answer 32

sickle cell anemia

Question 33

deoxygenated hemoglobin becomes…

Answer 33

insoluble and forms polymers that aggegate