01c: Oxidative Phosphorylation Flashcards

1
Q

Ox Phos: respiration depends on and is coupled to (X).

A

X = ATP phosphorylation

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2
Q

Experimentally adding mitochondria with succinate and P. What should be added to initiate oxygen consumption?

A

ADP

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3
Q

List the P/O ratios for NADH and FADH2.

A

NADH: 3 (new is 2.5)
FADH2: 2 (new is 1.5)

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4
Q

Experimentally adding mitochondria with succinate and P. Adding DNP will cause (stimulation/inhibition) of oxygen consumption.

A

Stimulation (without ADP) and rapid oxygen consumption;

DNP is an “uncoupler”

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5
Q

Experimentally adding mitochondria with succinate and P. After adding an inhibitor of ETC, what do you have to add to initiate oxygen consumption?

A

You can’t.. if the entire ETC is inhibited, oxygen consumption won’t occur

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6
Q

Experimentally adding mitochondria with succinate and P. After adding an inhibitor of phosphorylation, what do you have to add to initiate oxygen consumption?

A

DNP (uncoupler); even if phosphorylation inhibited, respiration can then proceed on its own

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7
Q

List the flavin carriers in ETC. How many hydrogens/electrons does each transport?

A

FAD and FMN;

2 hydrogens and electrons (FADH2, FMNH2)

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8
Q

The non-heme iron, aka (X), proteins are ETC carriers that transport (Y) number of hydrogens/electrons.

A
X = FeS;
Y = 1 electron
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9
Q

The heme iron, aka (X), proteins are ETC carriers that transport (Y) number of hydrogens/electrons.

A
X = cytochromes;
Y = 1 electron
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10
Q

CoQ, aka (X), is an ETC carrier that transport (Y) number of hydrogens/electrons.

A
X = Ubiquinone
Y = 2 hydrogens and electrons (QH2)
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11
Q

NADH gets oxidized by ETC complex (1/2/3/4), formally called (X), which passes the electrons to (Y).

A

Complex I
X = NADH-Q Reductase
Y = CoQ

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12
Q

CoQ receives electrons from which complex(es)?

A
  1. Complex I (NADH-Q reductase)
  2. Complex II (succinate dehydrogenase)
  3. ACD (acyl-CoA dehydrogenase)
  4. GPDHm (mito G3P dehydrogenase)
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13
Q

CoQ in ETC passes its electrons to (X).

A

X = Complex III (QH2-cytochrome c reductase)

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14
Q

Complex III passes electrons to (X) and then they’re passed to (Y).

A
X = cytochrome c
Y = Complex IV (cytochrome oxidase)
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15
Q

(X), the final electron acceptor in ETC, takes the electrons from (Y) carrier.

A
X = O2
Y = Complex IV (cytochrome oxidase)
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16
Q

T/F: All ETC complex pump H out of mitochondria matrix.

A

False - only complex I, III, IV

17
Q

Which complex is the ATP synthase?

A

Complex V

18
Q

Rotenone amytal inhibits (X) complex of ETC. Can electrons still get to CoQ?

A

X = Complex I (NADH-Q reductase)

Yes, via FAD dehydrogenases

19
Q

Antimycin A inhibits (X) complex of ETC. Can electrons still get to CoQ?

A

X = Complex III (QH2-cytochrome c reductase)

Yes, but ETC won’t work since can’t get past complex III

20
Q

CO is dangerous partly due to its inhibition of (X) ETC carrier.

A

X = Complex IV (cytochrome oxidase)

21
Q

Oligomycin is dangerous due to its inhibition of (X) ETC carrier.

A

X = Complex V (ATPase)

22
Q

ETC: The function of the (X) and (Y) shuttles is to shuttle what to where?

A
X = glycerol-P
Y = malate-asp 

Reducing equivalents from cytosol into mitochondria (to ETC)

23
Q

Which enzyme is key for the glycerol-P shuttle? Its product, (X), is capable of passing (Y).

A

G3P dehydrogenase
X = G3P or Dihydroacyteone-P (depending on direction of reaction)
Y = mito membranes

24
Q

In glycerol-P shuttle, the electrons are taken from (X) and given eventually to (Y).

A
X = NADH
Y = FAD (to become FADH2)
25
Q

In malate-asp shuttle, (X) takes electrons from (NADH/FADH2) and becomes (Y). Which enzyme catalyzes this?

A

X = oxaloacetate;
NADH;
Y = malate
Malate dehydrogenase

26
Q

T/F: Malate can cross mito membranes.

A

True

27
Q

In malate-asp shuttle, the electrons are taken from (X) and given eventually to (Y).

A

X = Y = NADH

28
Q

Aspartate aminotransferase (AST) is important enzyme in (X) because it converts (Y) to (Z).

A
X = Malate-asp shuttle
Y = oxaloacetate and Glu
Z = aspartate and alpha-ketoglutarate

(which can cross mito membrane)

29
Q

One of the first tests for liver damage is measuring (X) enzyme levels in blood, which would be (increased/decreased).

A

X = AST (Aspartate aminotransferase);

Increased (leak out of cells)

30
Q

All else equal, there is a difference of (X) ATP yield per glucose depending on if glycerol-P or Malays-asp shuttle used.

A

X = 2

Theoretically, GP shuttle gives 36 and M-A shuttle 38

31
Q

ETC: Membrane potential exists due to (X) process, which drives ATP (into/out of) mito.

A

X = H pumping (membrane more positive on outside);

Out via ANT (Adenosine NT Translocase) since ATP more negative than ADP

32
Q

What’s the mechanism of ETC uncoupling by poisons?

A

Carry protons across membrane to collapse H gradient

33
Q

T/F: In cases of ETC uncoupling, the ETC keeps pumping, despite lack of ATP synthesis.

A

True

34
Q

Actual ATP yield is (more/less) than the theoretical yield per glucose. Why?

A

Less (30 ATP);

Some E from proton needed to maintain membrane potential and drive ANT (Adenine NT translocase)

35
Q

ANT (Adenosine NT translocase) is important because it provides (X) with (Y). Explain.

A
X = ATP synthase
Y = ADP

Exchanges ATP (out) for ADP (into mito)

36
Q

Oligomycin inhibits (electron transport/mito phosphorylation).

A

Mito phosphorylation