Rate-determining enzymes of metabolic processes

Question 1

Glycolysis?

Answer 1

Phosphofructokinase 1

(+) AMP, Fructose 2,6 bisphosphate
(-) ATP, Citrate

Question 2

Guconeogenesis

Answer 2

Fructose 1,6 bisphosphatase

(+) ATP, acetyl-coA
(-) AMP, fructose 2,6 bisphosphate

Question 3

TCA cycle

Answer 3

Isocitrate dehydrogenase

(+) ADP
(-) ATP, NADH

Question 4

Glycogenesis

Answer 4

Glycogen synthase

(+) Glucose 6 phosphate, insulin, cortisol
(-) epinephrine, glucagon

Question 5

Glycogenolysis

Answer 5

Glycogen phosphorylase

(+) Epinephrin, Glucagon, AMP
(-) Glucose 6 phosphate, insulin, ATP

Question 6

HMP shunt

Answer 6

Glucose-6-phosphate dehydrogenase (G6PD)

(+) NADP+
(-) NADPH

Question 7

De novo pyrimidine synthesis

Answer 7

Carbamoyl phosphate synthetase II (cytoplasm)

(+) ATP
(-) UTP

Question 8

De novo purine synthesis

Answer 8

Glutamine-phosphoribosylpyrophosphate (PRPP) amidotransferase

(-) AMP, inosine monophosphate, GMP

Question 9

Urea Cycle

Answer 9

Carbamoyl phosphate synthetase I (mitochondria)

(+) N-acetylglutamate

Question 10

Fatty acid synthesis

Answer 10

Acetyl CoA carboxylase (ACC)

(+) insulin, citrate
(-) glucagon, palmitoyl-coA

Question 11

Ketogenesis

Answer 11

HMG-coA synthase

Question 12

Cholesterol synthesis

Answer 12

HMG-coA reductase

(+) insulin, thyroxine
(-) Glucagon, cholesterol

Question 13

Heme synthesis

Answer 13

(not metabolism related but still important)

Aminolevulinic acid synthase