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Flashcards in Lipolysis Deck (97):
0

Fatty acid oxidation bring the FA to where?

The mitochondria

1

What mobilizes the FA from triglycerides?

Lipases

2

Fatty acid oxidation activates the FA from?

acetyl CoA synthetase and pyrophosphatase

3

How is a FA transported into the matrix of the mitochondria?

By CPT and carnitine

4

Where is the FA transported to?

Then matrix of the mitochondria

5

FA oxidation makes what?

Makes ATP

6

FA oxidation enters the aerobic system(krebs and ETS) by multiple what?

Dehydrogenases

7

Hydrolysis of triglycerides is converted from glycerol to FA by what?

Lipases

8

Lipases TAG goes to DAG by what?

ATGL

9

Lipases DAG goes to MAG by what?

HSL

10

Lipases MAG goes to LCFA and glycerol by what

MGL

11

What are TAG broken down by? And what does it trigger?

Epinephrine and glucagon
And triggers the action of three lipases on a lipid droplet

12

What are the results of epinephrine and glucagon?

Low energy
Low blood sugar

13

What do 3 lipases on a lipid droplet trigger?

Lipases turn triglycerides into free fatty acids

14

Do hormones activate second messengers? And if they do what messengers are stimulated?

Yes, stimulates adenylyl Cyclades

15

What stimulates adenylyl Cyclase?

cAMP
AMP kinase PKA

16

What does PKA stimulate?

Stimulates Lipolysis in fat cells

17

By breaking down a TAG what does it activate?

Activated HSL hormones sensitive lipase

18

What is HSL activated by?

Phosphorylation
DAG to MAG

19

AMP stimulates

Glut4
Glycogen breakdown
Glycolysis
LPLm activation
Fat Burning

20

AMP inhibits?

Glycogen synthesis
TAG synthesis
Cholesterol synthesis
FA synthesis

21

What does insulin do in breaking down TAG?

De phosphorylates HSL
inhibits ATGL

22

What is the fate of glycerol?

Transported in blood to the liver

23

What is glycerol transported by?

Phosphorylated to glycerol 3 phosphate

24

Glycerol 3 phosphate does what?

TAG synthesis
Phospholipid synthesis
DHAP glycolysis and gluconeogenesis

25

Glycerol 3 phosphate is transferred to dihydroxyactone phosphate by what enzyme?

By glycerol 3 phosphate dehydrogenase

26

What is a free fatty acid transported in?

Transported in the blood

27

Free fatty acid in the blood is bound to what and sent to where?

Bound to serum albumin
Sent to target tissues skeletal heart renal cortex and is a fuel source

28

How many free fatty acids can albumin carry?

Can army 10 free fatty acids pet protein monomer

29

What does a FA enter in order to degrade?

Enters the muscle

30

When a FA is activated what does it turn in to?

Acyl CoA

31

FA degradation what does it specifically enter?

The mitochondria

32

Where is a FA in degradation oxidized at?

In the mitochondria OHOT

33

A FA entering the muscle must be chaperoned by a? And escorts it to where?

Protein and is escorted to the surface of the mitochondria

34

Activation of the FA happens how?

Attaching a coenzyme A to the FA Snd crating Acyl CoA

35

After the coenzyme A is attached to the FA and creates Acyl CoA the enzyme is Acyl CoA synthetase it is about to enter what?

The mitochondria

36

Activating the FA is driven by what?

Driven by ATP

37

What is the location that the FA activation takes place?

The outer mitochondrial membrane

38

By activating the FA it does what?

Links between CoA and the fatty acid

39

What is consumed in the process of activating the FA?

ATP

40

ATP is what

AMP + PPi

41

PPI is

2Pi + energy
Pyrophosphotase

42

Pyrophosphotase is what to make the reaction irreversible

Is hydrolyzes
This is common in biosynthesis

43

After hydrolization we do what?

Oxidation

44

What does the CPT (carnitine palmitoyltransferase complex) consists of?

CPT I
Acylcarnitine translocase
CPT II

45

What is the CPT complex responsible for?

Transport of LCFAs

46

What is CPT I considered?

The rate limiting step

47

What's another name for acylcarnitine translocase?

Carnitine acyltransferase

48

CPT complex is reversible inhibited by?

Malonyl CoA (first committed step in FA synthesis)

50

CPT complex is kept at a neutral pH optimum and is inhibited when?

From pH decrease 7.0 to 6.8

51

in the cytosol is where the BLANK are?

the regulatory sites
lactic acid or PH

52

where are the regulatory sites?

on the CPT I

53

What four steps does Beta oxidation refer to?

these steps occur prior to having fat enter the aerobic system
Oxidation
Hydration
Oxidation
Thiolysis

54

During the oxidation phase what occurs?

Acyl CoA converted to Trans Enoyl CoA by Acyl CoA dehydrogenase and loses a FAD to go to a FADH2

55

During the hydration phase what occurs?

trans enoyl CoA is converted to L-3 hydroyacyl CoA by enoyl CoA hydrotase and water is added

56

What occurs during oxidation II phase?

3 hydroxyacyl CoA is converted to 3 ketone CoA by L-3 hydroxyacyl CoA dehydrogenase and NAD+ is lost to go to NADH + H+

57

During the thiolase phase what occurs?

3 ketoacyl CoA is converted to Acyl CoA (minus 2) or Acetyl CoA by B ketothiolase while CoA-SH is added to the reaction

58

What does oxidation produce? and by what?

produces a double bond and FADH2
Dehydrogenase

59

By adding water (a hydroxyl group) and removing a double bond what is the enzyme?

hydratase

60

What does the second oxidation turn the hydroxyl group into?

into a carbonyl group
dehydrogenase

61

Oxidation and hydration in the krebs cycle is what?

Succinate to Fumarate by:
Succinate dehydrogenase
and fumarate to malate by:
Fumarase

62

In the krebs cycle what is Malate converted to and by what?

converted to oxaloacetate and by malate dehydrogenase

63

What are FADH2 and NADH?

both are products that got to the ETS

64

What is Acetyl CoA? what does it enter? what does it produce?

is a product
enters the krebs cycle
produces reduced coenzymes FADH2 and NADH to be sent to ETS

65

what happens to the Acetyl CoA each time you run the B-Oxidation (OHOT)?

is two carbons shorter each time you run the B-oxidation OHOT

66

unsaturated FA degradation?

many of the reactions are the same
two additional enzymes are required

67

what are the two additional additional enzymes required?

reductase and isomerase

68

what two things are the same at getting into the matrix?

translocation and activation

69

What occurs during oxidation?

Acyl CoA to 2,4 dienoyl CoA by Acyl CoA dehydrogenase
FAD enters and leaves as FADH2

70

What occurs during reductase?

2,4 dienoyl CoA to cis enoyl CoA by 2,4 dienoyl CoA reductase
NADPH + H+ enters and leaves as NADP+

71

What occurs during isomerase? (new step)

cis enoyl CoA to trans enoyl CoA by isomerase

72

What occurs during hydration?

trans enoyl CoA to L-3 hydroxyacl CoA by enoyl CoA hydratase and water is added

73

What occurs during Oxidation II?

L-3 hydroxyacyl Coa to 3 ketoacyl CoA by L-3 hydroxyacyl CoA dehydrogenase
NAD+ enters and leaves as NADH + H+

74

What occurs during thiolase?

3 ketoacyl CoA to acyl CoA or Acetyl CoA by beta ketothiolase
CoA-SH enters in

75

what fats require one or two extra enzymes?

polyunsaturated

76

what are odd numbered double bonds? how do they get degraded?

isomerase
degrade two by two just like even chain FA

77

what are even numbered double bonds? how do they get degrade?

reductase and isomerase
they get degraded two by two just like odd chain FA

78

what is the difference between odd and even chain FA?

Odd chain FA are let with propionyl CoA

79

what is propionyl CoA converted to?

succinyl CoA
this conversion is common in converting AA into TCA intermediates

80

what is required for FA oxidation regulation?

energy required

81

what are the energy requirements?

Liver
high NADH/ NAD+ ratio
high concentration of acetyl CoA

82

what does the energy requirement of the liver do?

need energy B xidation in mitochondria
do not need energy form TAG and phospholipids cytosol

83

what does the energy requirement high NADH/NAD+ do?

signals high energy
inhitbits 2nd oxidation step (3 hydroxacyl CoA dehydrogenase?

84

what does concentration of acetyl CoA do?

inhibtis thiolase

85

what is carnitine shuttle and what does it do in the FA oxidation regulation?

is the rate limiting step
FA in mitochondria committed to B oxidation

86

what does glucose do in FA oxidation regulation?

increased glucose increases malonyl CoA
inhibits CPT I inhibits B oxidation

87

what does AMP do in FA oxidation regulation?

exercise or fasting increases concentration of AMP
AMPkinase
stimulate FA oxidation inhibits FA synthesis

88

regulation and stimulation

hormones
epinephrine norepinephrine glucagon
AMP (cAMP)
low energy

89

regulation and inhibition

hormone
insulin
high glucose
high energy
high NADH/NAD+
malonyl CoA

90

what are the key enzymes in FA oxidation?

lipases
acyl CoA cynthetase
acyl Coa dehydrogenases

91

lipases are

free fatty acids from triglycerides

92

acyl CoA sythetases

activates the FA for transport into the mitochondria

93

Acyl CoA dehydrogenases

first enzyme of OHOT (B oxidation)
oxidizes acyl CoA

94

FA oxidation (has 7 things):

mobilizes the FA from Triglyceride- lipases
bring the FA to the mitochondria
activate the FA- acyl CoA synthetase and pyrophosphatase
transport the FA into the matrix of the mitochondria- CPT and carnitine
Beta oxidation- OHOT (acyl CoA Dehydrogenase)
enter the aerobic system(krebs ETS)- multiple dehydrogenases
makes ATP

95

HSL is strongly inhibited by>

insulin

96

ATGL is elevated in

type II diabetics

97

HSL exhibits a 10 fold higher specific activity for

DAG from TAG