Synthesis of fatty acids Flashcards
what is fatty acid synthesis not the reverse of
b oxidation
where does fatty acid synthesis occur
in the cystol of our liver cells and in lactating mammary glands
what are the reductants in fatty acid synthesis
NADPH
why does elongation occur
due to the sequential addition of two carbon units derived from the acetyl CoA
when does elongation stop
at 16 carbohydrates
where are enzymes attached
to a single poly peptide chain “fatty acid synthase”
how do we remove xs citrate from the TCA cycle
via the pyruvate malate cycle
how does the pyruvate malate cycle work
citrate is moved out of the matrix by a transport protein and then converted back into oxaloacetate and Acetyl CoA by ATP citrate lyase using ATP
why is the pyruvate malate cycle important
it is a way of getting citrate out of the cycle
and it is a source of NADPH production
what is insulin uprugulate
ATP citrate lyase
what is the RDS in forming fatty acids
malonyl CoA step
describe the formation of malonyl coA
CO2- biotin enzyme + acetyl coA —-> malonyl coA + biotin enzyme using the enzyme acetyl coA carboxylase( biotin) and citrate
how is the formation of of malonyl coA regulated
by a high AMP:ATP ratio
and by insulin
and glucagon and epinephrine( inhibit phosphatase)
how does a high AMP:ATP ratio regulate malonyl coA formation
as the enzyme kinase is used and ATP to inactivate the acetyl CoA carboxylase enzyme
how does insulin regulate malonyl coA formation
as insulin up regulates the enzyme phosphatase which converts the inactive form of acetyl coA carboxylase into the activated from
what is a derivative of pantothenic acid (vitamin B5)
4’ phosphopentetheine
what does 4’ phosphopentetheine carry units
acetyl and acyl units on the terminal thiol group during fatty acid synthesis
describe step 1
acetyl coA + ACP-SH via the enzyme Acetyl Coa ACP transacylase—> to form acetyl S ACP + coA
what is the end product of fatty acids synthesis
palmitate
