FA synthesis Flashcards
lipids are stored in ____ form ( more compact)
anhydrous
lipids - fatty acids are more _____ than amino acid or monosaccharides (CHO)
reduced (CH2)
Fatty acid synthesis. the point is, ?
store carbon and electrons **(e- from pentose pathway)
in form of reduced carbon which you will later oxidize to CO2
FA biosynthesis located?
cytoplasm*
FA breakdown located?
mitochondrial matrix/peroxisomes
FA synthesis - requird what in cytoplsm?
acetyl coa and NADPH
FA synthesis - rate limiting step
carboxylation of acetyl coa –> malonyl coa(C3)
5 step reaction catalzed in mammal by?
fatty acid synthase
acetyl coa is primarily found in where?
mitochondrial matrix
acetly coa to cytosol
acetyl coa and amino acid is exported from mitochondria via what system?
citrate transport system ( citrate malate pyruvate shuttle)
citrate malate pyruvate shuttle
citrate is easy to move around in membrane
shuttle system: fatty acid
2C from acetyl coa
NADPH
this catalyzes the rate limiting step of FA synthesis (uses biotin)
Acetyl Coa carboxylase
this typically acts as a CO2 carrier/activator - bound to e-NH3 of lysines
Biotin
Malonyl transfererase is how specific?
very specific
acetyl transferase is how specific?
less
odd number of chain FA are built starting with____?
proprionyl group (C3) instead of acetate (C2)
FA synthesis, what is the reducing agent?
NADPH
Fats are storing electron*
final reaction of FA synthesis, rounds of synthesis continue until ____group is formed
C16 palmitoyl group
palmitoyl-ACP is hydrolyzed by?
thioesterase
break carbon sulfur bond
respiratory distress syndrome in infant due to what?
surfactant
four levels of regulation of FA synthesis
- transcriptional regulation
- polymerzation
- phosphorylation
- hormones
Allosteric control by palmitoyl CoA and citrate?
polymerization of ACC
polymer ( = active)
to make longer FA, where it’s made?
ER
Humans can’t make FA with ___or ____from the w end
double bonds 3 carbons (w3) or 6 carbons (w6)
thus, these are essential FA***
derivatives of 20 carbon polyunsaturated FA to make ____?
eicosanoids
once tricyglycerol is made, FA’s are bound to ____ for storage as TAGs
glycerol
triacylglycerol is made only in ?
eukaryote
where triacylglycerol is made via a phosphatidic acid intermediate?
In liver and adipose tissue,
FAS is proposed to act as ___?
oncogene – overexpression correlated with some tumors, e.g. prostate, may be target for treatment
Fatty acid synthase is regulated primarily by?
Transcriptional regulation
regulation of AcetylCoA carboxylase (ACC), the RATE LIMITING step of fatty acid synthesis, with regulation of the actual fatty acid synthase complex, which it seems is only regulated at transcriptional level
