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Flashcards in Unit 5A Deck (16)
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1

Site of catabolism:
Site of anabolism

Catabolism- mitochondria
Anabolism- cytosol

2

Catabolism produces:

Acetyl-CoA and NADH (reducing power)

3

Anabolism requires:

Acetyl-CoA
Malonyl-CoA
Reducing power from NADPH

4

What happens in the cytosol

NADPH production

Storage of NADPH/NADP+

Isoprenoid and sterol synthesis (early stages)

Fatty acid synthesis

5

What happens in the mitochondria in animals and yeast cells

Fatty acid oxidation

Acetyl-CoA production

Ketone body synthesis

Fatty acid elongation

6

What happens in the ER

Phospholipid synthesis

Sterol synthesis (late stages)

Fatty acid elongation

Fatty acid desaturation

7

Fatty acid synthesis occurs where?

In cell compartments where NADPH levels are high and available for reductive synthesis (Cytosol for animals)

8

Sources of NADPH in adipocytes:

Pentose phosphate pathway (PPP) and malic enzyme.
Here NADPH made as malate converts to pyruvate + CO2

9

Sources of NADPH in hepatocytes and mammary gland

Pentose phosphate pathway (PPP)

Here, NADPH is made as glucose-6-phosphate converts to ribulose-6-phosphate

10

2 routes to produce NADPH and their catalyst

1- Malate to pyruvate. Coenzyme: Malic enzyme

2- Glucose-6-phosphate to ribulose-5-phosphate.
Coenzyme: PPP

11

Steps in fatty acid biosynthesis

1- Shuttle of acetyl-coa to cytosol via citrate shuttle

2- Carboxylation of acetyl-coa to malonyl coa via acetyl-coa carboxylase (ACC)

3- Reactions of FA syntheses (remember CRDR)

12

How is acetyl-coa transported into the cytosol for FA synthesis?

Acetyl-coa is converted to citrate with oxaloacetate (catalyzed by citrate synthase)

Citrate then passes through the citrate transporter

13

Citrate in the cytosol is cleaved by _____ _____, regenerating:

citrate lyase

acetyl-coa and oxaloacetate (Reaction requires ATP)

Acetyl Coa can now be used for lipid synthesis

14

Malate dehydrogenase in the cytosol reduces to:

malate

15

In the cytosol, what can happen to malate?

It can be converted to NADPH and pyruvate via the malic enzyme

or it can be converted back to the mt via malate-a-ketogluterate transporter

16

NADPH is used for

lipid synthesis