Metabolism Biochemistry (Enzymes and pathways) Flashcards
What is metabolized in the mitochondria?
- Fatty acid Beta oxidation
- CoA production
- TCA Cycle
- Oxidative phosphorylation
What is metabolized in the cytoplasm?
- Glycolysis
- Fatty acid synthesis
- HMP Shunt
- Protein synthesis
- Steroid synthesis
- Cholesterol synthesis
What reactions can occur in both the mitochondria and the cytoplasm?
- Heme synthesis
- Urea cycle
- Gluconeogensis
What is the rate limiting enzyme of glycolysis?
Phosphofructokinase-1
What is the rate limiting enzyme of gluconeogenesis?
Fructose-1,6-bisphosphatase
What is the rate limiting enzyme of the TCA cycle?
Isocitrate dehydrogenase
What is the rate limiting enzyme of glycogenesis?
Glycogen synthase
What is the rate limiting enzyme of glycogenolysis?
Glycogen phosphorylase
What is the rate limiting enzyme of the HMP Shunt?
G6PD
What is the rate limiting enzyme of de novo pyrimidine synthesis?
Carbamoyl phosphate synthetase II
What is the rate limiting enzyme of de novo purine synthesis?
Glutamine-PRPP-amidotransferase
What is the rate limiting enzyme of urea cycle?
Carbamoyl phosphate synthetase I
What is the rate limiting enzyme of fatty acid synthesis?
Acetyl-CoA carboxylase
What is the rate limiting enzyme of fatty acid oxidation?
Carnitine acyltransferase I
What is the rate limiting enzyme of ketogenesis?
HMG-CoA synthase
What is the rate limiting enzyme of cholesterol synthesis?
HMG-CoA reductase
How many ATP can be generated from glucose when the malate aspartate shuttle is used?
32
How many ATP can be generated from glucose when the glycerol-3-P shuttle is used?
30
What is the first step of glycolysis?
Glucose -> Glucose-6-P, means the glucose is trapped in the cell
What enzyme catalyzes the first step of glycolysis?
- Hexokinase in MOST tissues
2. gLucokinase in LIVER
What enzyme that phosphorylates glucose is induced by insulin?
Glucokinase
Glucose-6P ->Fructose-6P->Fructose-1,6BP is sent on through glycolysis if the person is in what state?
Fed state, insulin around
Glucose-6P ->Fructose-6P->Fructose-1,6BP is sent on to what process if in the fasting state? What enzymes are involved?
Gluconeogenesis, FBPase-1 sends it back to F-6P
What cofactor does arsenic inhibit?
Lipoic acid
What builds up if there is a pyruvate dehydrogenase complex deficiency? What clinical findings present?
Lactate and Alanine -> Lactic acidosis and neurologic defects
What reactions of the TCA cycle generate GTP?
Succinyl-CoA -> Succinate
What reactions of TCA cycle generate NADH?
- Isocitrate -> Alpha-ketogluterate
- Alpha-ketogluterate ->Succinyl-CoA
- Malate ->Oxaloacetate
What reactions of the TCA cycle generate FADH2?
Succinate ->Fumarate
What are the irreversible enzymes of Gluconeogenesis?
- Pyruvate carboxylase
- Phosphoenolpyruvate carboxykinase
- Fructose -1,6-Bisphosphatase
- Glucose-6-Phosphatase
What is the use of the HMP Shunt? Where is it performed?
- Generates NADPH (reducing power)
- Liver, adrenal cortex, RBCs
What agents can induce hemolysis in G6PD patients?
- Fava beans
- Sulfonamides
- Primaquine