Biochem lec 3 - Lipid Metabolism - De novo synthesis of fatty acids

Question 1

carbs and proteins obtained from the diet in excess of the body’s needs can be convereted to what and how is it stored

Answer 1

converted to fatty acid which are stored as triacylglycerols

Question 2

where does adult FAs synthesis occur

Answer 2

-liver (mainly)
-lactaing mammary glands
-adipose tissue (to a lesser extent)

Question 3

where does FA synthesis occur

Answer 3

cytosol

Question 4

what happens in FA synthesis

Answer 4

incorporates carbons from acetyl CoA into the growing fatty acid chain using ATP and NADPH

Question 5

how are FAs synthesized

Answer 5

by repetitive addition of 2 carbon units to the growing end of the hydrocarbon chain

Question 6

what is the first step of de novo synthesis of FA

Answer 6

production of cytosolic acetyl CoA
citrate crosses the membrane to the cytosol where it is reconvereted to oxaloacetate and Acetyl-CoA

Question 7

Acetyl-CoA from where must go where

Answer 7

from the mitochondrion to the cytosol

Question 8

step 2a

Answer 8

conversion of acetyl CoA into acetyl-ACP

Question 9

step 2b

Answer 9

conversion of acetyl CoA into malonyl CoA

Question 10

3a

Answer 10

conversion of acetly ACP into acetyl synthase

Question 11

3b

Answer 11

conversion of malonyl CoA into Malonyl-ACP

Question 12

synthesis of Palmitate by what

Answer 12

multifunctional fatty acid synthase (FAS)

Question 13

where does further elongation of fatty acid chains occur

Answer 13

in the smooth ER by the addition of 2 carbon units
malonyl CoA is the 2 carbon donoar and NADPH supplies the e-