regulation of PFK1

Question 1

In eukaryotes….

Answer 1

• PFK is homotetrameric
• equilibrium between T state (less active) and R state (more active)

Question 2

Describe the catalytic site of PFK1

Answer 2

where F6P and ATP that is used as S will be binding.
Surrounding allosteric sites are in junctions of subunits

Question 3

PFK1 catalytic vs allosteric ATP binding sites

Answer 3

catalytic: ATP + F6P

Allosteric: (gets used when have high concentrations of ATP.

Question 4

describe function of FBP

Answer 4

binds near dimerization and tetramerization sites to stabilize the R state.
Subunits dimerize, then tetramerize which is what stabilizes the R state

Question 4

Describe PFK1 dimer

Answer 4

PFK1 dimer is inactive, but can tetramerize to become inactive or active (acitve if it’s in R state)

Question 5

Effects of binding ATP or citrate (allosteric effectors) to regulatory site of PFK1

Answer 5

decreases PFK1’s affinity for F6P

NOT referring to catalytic ATP, REFERRING TO N1 ATP

Question 6

AMP control over PFK1

Answer 6

AMP control not fully known, can increase PFK1’s affinity for F6P