2.6 Fatty Acid Biosynthesis Flashcards
What is the main substrate for synthesis?
Acetyl CoA
Where does Fatty Acid Biosynthesis occur?
Cytosol of Liver
How does Acetyl CoA move across the mitochondrial membrane?
Acetyl CoA + Oxaloacetate = Citrate
Citrate can be moved across the membrane
What enzyme catalyzes reaction of Acetyl CoA and Oxaloacetate to Citrate
Citrate Synthase
What enzyme catalyzes the reaction that occurs to take Citrate to Acetyl CoA and Oxaloacetate
Citrate Lyase
What 3 things regulate FA biosynthesis
High Citrate
High ATP
High Acetyl CoA
WHat enzyme catalyzes reaction of Acetyl CoA to Malonyl CoA
Acetyl CoA Carboxylase
What is the coenzyme in the reaction of acetyl CoA to Malonyl COA
Biotin
What is the rate limiting step of FA biosynthesis
Acetyl CoA –> Malonyl CoA
Carboxylation reactions require what three things?
Biotin
ATP
CO2
How is Acetyl CoA Carboxylase activated?
PP2A dephosphorylates Acetyl CoA Carboxylase
What three things regulate Acetyl CoA Carboxylase
High levels of AMP deactivate
High levels of Insulin
Low levels of Glucagon and Epinephrine
T or F, High levels of Citrate promote FA biosynthesis
True
Low levels of Malate and Epinephrine do what to Acetyl CoA Carboxylase?
They Activate the enzyme and therefore promote FA synthesis.
What are the normal substrates to form a Palmitate molecule
8 Acetyl CoA, 14 NADPH, 7 ATP, 14 H+
What four reactions are involved in Fatty Acid synthesis
Condensation –> Reduction –> Dehydration –> Reduction
In what two pathways does the NADPH come from that helps FA Synthesis
Pentose Phosphate Pathway
Malate to Pyruvate
What do you lose when Acetyl CoA is added to Malonyl CoA
CO2 (condensation)
When the four carbon unit is removed from ACP and moved to CE acp, what is needed?
2 NADPH
Where does Fatty Acid ELongation occur?
on the cytoplasmic face of ER
What enzyme is involved in Fatty Acid Elongation
Fatty Acid Elongase
Fatty Acid Desaturation takes place where and by what enzyme?
In the ER
Fatty Acid Desaturase
What are the essential precursors of TAGs
G3P
DHP (Dihydroxyacetone Phosphate)
FFA
Phosphatidate
Where are TAGs synthesized
Liver and Adipose tissue
