Rate limiting steps of metabolism

Question 1

Glycolysis

Answer 1

Phosphofructokinase-1 (PFK-1)

+ by AMP and fructose-2,6-bisphosphate
- by ATP and citrate

Question 2

Gluconeogenesis

Answer 2

Fructose-1,6-bisphosphatase

+ by citrate
- by AMP and fructose-2,6-bisphosphate

Question 3

TCA cycle

Answer 3

Isocitrate dehydrogenase

+ADP
-ATP, NADH

Question 4

Glycogenesis

Answer 4

Glycogen synthase

+ by G-6-P, insulin, cortison
- by Epi and glucagon

Question 5

Glycogenolysis

Answer 5

Glycogen phosphorylase

+ by Epi, glucagon and AMP
- by G6P, insulin and ATP

Question 6

HMP shunt

Answer 6

G6P dehydrogenase

+ NADP+
- NADPH

Question 7

De novo pyramidine synth

Answer 7

Carbamoyl phosphate synthase II

+ ATP PRPP
- UTP

Question 8

De novo purinie synth

Answer 8

Glutamine-phosphoribosylpyrophosphatase amidotransferase

-AMP, IMP, GMP

Question 9

Urea cycle

Answer 9

Carbamoyl phosphate synthase I

+ N-acetylglutamate

Question 10

FA synthesis

Answer 10

Acetyl-CoA carboxylase

+ Insulin, citrate
- glucagon, palmitoyl-CoA

Question 11

FA oxidation

Answer 11

Carnitine acyltransferase I

-malonyl CoA

Question 12

Ketogenesis

Answer 12

HMG CoA synthase

Question 13

Cholesterol synthesis

Answer 13

HMG CoA reductase

+insulin, thyroxine
- glucagon, cholesterol