module 9- Fatty acid synthesis Flashcards
(47 cards)
location of fatty acid synthesis
cytosol
ATP-citrate lyase
cleaves citrate into acetyl CoA & oxaloacetate
what enzyme catalyzes acetyl CoA + oxaloacetate -> citrate
citrate synthase
oxaloacetate is reduced using?
NADH
malic enzyme
malate -> pyruvate
pyruvate fate
back to mitochondria to make more acetyl CoA
how is acetyl CoA activated
by converting it to malonyl CoA
acetyl CoA carboxylase
acetyl CoA -> Malonyl CoA
what enzyme contains biotin group
acetyl CoA carboxylase
palmitate
16 carbon saturated fatty acid, synthesized via 4 reactions
fatty acid synthase complex
large enzyme system that synthesizes fatty acids
fatty acid synthase complex in plants vs yeast vs vertebraes
plants- made of individual proteins
yeast- made of 2 polypeptides
vertebrates- made of 1 polypeptide
acyl carrier protein (ACP)
has phosphoantetheine group, acts as an arm to synthesize palmitate
odd chain fatty acids begin with ( ) and even chain ( )
propionate, accetyl CoA
4 steps of FA synthesis & their enzymes
1) condensation- B-ketoacyl synthase
2) reduction- b-ketoacyl reductase
3) dehydration- 3-hydroxyacyl dehydratase
4) reduction- enoyl reductase
in order to complete the synthesis of a free fatty acid, ( ) must be released from ACP
palmitate
what enzyme produces palmitate at the last step of FA synthesis
thioesterase
how many molecules of NADPH are required for 1 FA synthesized?
14
for every acetyl CoA brought into the cytosol, ( ) molecule of NADPH is also produced
1
how many molecules of acetyl CoA & NADPH to make palmitate
8, 8
where do the other 6 molecules of NADPH for palmitate synthesis come from?
pentose phosphate pathway
T or F: tumors high have need for FA
T
what enzyme can be used to inhibit tumors
B-ketoacyl ACP synthase
longer fatty acids are made by adding ( ) carbon-units to the carboxyl end using ( ) as the substrate
2, malonyl CoA
