pyruvate dehydrogenase and citric acid cycle Flashcards Preview

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Flashcards in pyruvate dehydrogenase and citric acid cycle Deck (49):
1

where are PDH and TCA located?

in the matrix of mitochondria

2

what is the purpose of pyruvate dehydrogenase for the TCA cycle?

to make pyruvate so that it can be converted to acetylcoA

3

What is the main structure in the cell that produces ATP?

the mitochondria/ power plant

4

What is the purpose of the TCA cycle?

to produce energy

5

what are the fates of pyruvate?

lactate, oxaloacetate, alanine, acetyl CoA

6

what is the process called when pyruvate forms alanine?

transamnation-transfer ofone amino group to another

7

what is the process called that allows for pyruvate to be transfered into oxaloacetate?

carboxylation

8

when pyruvate is oxidized and decarboxylated what does it form?

Acetyl CoA

9

when pyruvate is reduced what is formed?

lactate

10

how is acetyl CoA oxidized further?

it enters the TCA cycle

11

what are some important intermediates in the TCA cycle that can be derived from other process?

Succinyl CoA, Oxaloacetate, Fumarate, alpha ketoglutarate

12

what are the two reasons that pyruvate dehydrogenase is important?

because it is the link between glycolysis and the kreb cycle and it also provides us with energy

13

what are the three catalytic enzymes for the pyruvate dehydrogenase complex?

pyruvate dehydrogenase, dihydrolipoyl dehydrogenase, and dihydrolipoyl transacetylase

14

what are the regulatory proteins involved in the pyruvate dehydrogenase complex?

protein kinase(phosphorylation) and protein phosphatase (dephosphorylation)

15

what are the 5 coenzymes in the pyruvate dehydrogenase complex?

CoAsh, FAD, NAD, thiamine pyrophosphate (TTP), lipoic acid

16

is PDH only found in the mitochondrial matrix?

YES

17

in the PDH complex, pyruvate is decarboxylated by pyruvate dehydrogenase and transfers what group to the acyl carrier ?

transfers the acetyl group to pyrintriphosphotase (acyl carrier)

18

after being transfered to pyrintriphosphate the acetyl group is then phosphorylated to

acyl lipoate (Dihydrolipoyl transacetylase- acetyl carrier)

19

what does acyl lioate get converted to ?

CaAsh to acetyl CoA

20

when lipoic acid is reduced, the electrons can be oxidized to and will transfer its elecrtrons to?

FAD--> FADH2

21

after FADH2 is formed from getting electrons from the oxidized lipoic acid what will it do with these electrons?

it passes them yo NAD+ to NADH (electron carries dihydrolipoyl dehydrogenase)

22

what activates PDH?

dephosphorylation, insulin in adipocytes and liver, catecholamines in cardiac muscle, calcium in skeletal muscle

23

what inhibits PDH?

phosphorylation, acetyl CoA, ATP, NADH

24

is PDH activated when it is phosphorylated?

no it is inactive

25

what would be needed to activate the phosphorylated PDH?

PDH phosphotase

26

how is PDH phosphotase activated?

by Ca+ and Mg+2

27

what are NADH, ATP, ACETYL-CoA used for in the PDH complex?

PDH kinase

28

how many acetyl CoA's will go into the TCA cycle?

2

29

what are the two amino acidsthat can form acetyl CoA?

leucine, lysine

30

what are the three fates of acetyl CoA?

tricarboxylic acid cycle, ketone bodies, sterols- fatty acids

31

howmany carbons does citrate have?

6

32

in the kreb cycle, what happens with cisaconitrate and isocitrate?

isomerization

33

with isocitrate to oxalosuccinate when using isocitrate dehydrogenase what happens that is important here?

the first electron accepted ( NAD+ to NADH+H+)

34

from oxalosuccinate to alpha keto glutarate using isocitrat dehydrogenase what is lost?

the first carbon is lost by way of carbon dioxide

35

from alpha keto glutarate to succinyl CoA, what happens here?

the second carbon is lost andthe second NADH to NAD+ occurs

36

from succinyl CoA to succinate how many carbons do you have?

4

37

what is formed when succinyl CoA synthetase is used to transfer succinly CoA to succinate?

GTP

38

when succinate is changed to fumarate by succinate dehydrogenase what happens here?

FAD forms FADH

39

from fumarate to L malate what enzymeis used?

fumarase

40

from L-Malate to oxaloacetate by malate dehydrogenase what happens here?

the last electron transfer exchange of NAD+ to NADH happens

41

when oxaloacetate accepts acetyl CoA into the kreb/citrate cycle what does it form?

citrate(6 carbon sugar)

42

what changes oxaloacetate to citrate?

citrate synthetase

43

what enzymes aid in the process of NAD to NADH?

isocitrate DEHYDROGENASE, a-ketogltarate DEHYDROGENASE, malate DEHYDROGENASE

44

What enzyme aids in FAD to FADH?

succinate DEHYDROGENASE

45

When is GTP formed with what enzyme?

succinyl CoA synthetase

46

where are the two carbons relased?

isocitrate dehydrogenase, and alpha ketoglutarate dehydrogenase

47

How may times is H2O fed in this cycle?

3, before and after aconitase, and at fumarase

48

How much ATP is made in the kreb cycle?

2atp/ acetyl coA oxidized but since 2 then it is 24 ATP

3 NADH (9 ATP)
1 GTP (1 ATP)
1 FADH2 (2 ATP)

49

what are the 2 diseases that are caused by thiamine deficiency?

werneke-korsakoff syndrome, and wet beri beri