oxidative phosphorylation

Question 1

what is Oxidative phosphorylation

Answer 1

Oxidative phosphorylation is a cellular process that harnesses the reduction of oxygen to generate high-energy phosphate bonds in the form of adenosine triphosphate (ATP).

Question 2

Identify and rank electron affinity of the 6 mitochondrial
electron carriers

Answer 2

Nicotinamide(NAD+)<Flavins(FAD+)<Iron-sulfur centers<ubiquinone(Q)<cytochromes<copper centers

Question 3

where can we get nicotinamide

Answer 3

VB3,

Question 4

what’s the abbrvation for nicotinamide?

Answer 4

NAD+, NADH

Question 5

how many electrons could NAD+ accept?

Answer 5

2

Question 6

where can we get flavins?

Answer 6

riboflavin VB2

Question 7

what can flavins do?

Answer 7

FMN(complex I)/FAD(complex III)

Question 8

how many electrons can FMN/FAD accept?

Answer 8

2

Question 9

where can we find iron-sulfur center in electron-transport chain?

Answer 9

complex I

Question 10

how many electrons could iron-sulfur center accept?

Answer 10

1

Question 11

what’s unique about ubiquinone(Q) structure?

Answer 11

has a hydrophobic tail

Question 12

ubiquinone(Q) is the oxidized form or reduced form

Answer 12

oxidized form

Question 13

how many electrons is needed to fully reduce ubiquinone(Q)

Answer 13

2

Question 14

what’s special about the structure of cytochrome?

Answer 14

Heme(Fe3)-containing proteins,

Question 15

how many electrons could cytochrome accept?

Answer 15

1 (Fe3+ —–>Fe2+)

Question 16

where can we find copper center?

Answer 16

complex IV

Question 17

how many electrons could copper center accept?

Answer 17

1 (Cu2+ —> Cu+)

Question 18

what’s the electron transport chain?

Answer 18

complex I(NADH)
Q—>complex III —->cytochrome c —->complex IV—>O2
Complex II (e from CAC)

Question 19

how is NADH made in cytosol

Answer 19

During glycolysis, malate-aspartate shuttle moves electrons into matrix

Question 20

net reaction of NADH dehydrogenase (complex I)

Answer 20

NADH + Q + 5H+(mat) —>NAD+ + QH2 + 4H+(IM)

Question 21

name of complex I?

Answer 21

NADH dehydrogenase

Question 22

how many protons pumped out after complex I? For every 1 NADH

Answer 22

4 H+

Question 23

Copper ions are usually bound to proteins through which amino acid residue(s)？

Question 24

Which statement best describes the normal proton-pumping activity of cytochrome oxidase (Complex IV)?

Question 25

Which of the following members of the electron transport system is not a protein or a group of proteins?

Question 26

Consider the electron carriers NADH and QH2. Which can be found at a significant concentration as a free molecule in the mitochondrial matrix?

Question 27

Consider the electron carriers NADH, QH2, and cytochrome c. Which of these is embedded directly in a lipid bilayer?

Question 28

proton movement direction electron transport chain in mitochrodia

Answer 28

protons from matrix to intermembrane space

Question 29

net reaction of complex I(NADH dehydrogenase)

Answer 29

NADH + Q + 5H+(mat) -------NAD+ + QH2 + 4H+(IM)

Question 30

how many protons pumped out when every 1 NADH reacted at NADH dehydrogenase

Answer 30

4

Question 31

matrix part of complex I

Answer 31

L-shape, flavin and iron-sulfur center

Question 32

complex III name

Answer 32

Cytochrome b-c1 complex

Question 33

where's cyt.c located, matrix or intermembrane space?

Answer 33

intermembrane space

Question 34

net reaction of complex III

Answer 34

QH2 + 2 cyt c (ox)+ 2H+(mat)------Q + 2 cyt c (red)+ 4H+(IM)

Question 35

how many protons pumped out for every 1 QH2 reacted at Cytochrome b-c1 complex

Answer 35

4

Question 36

Q-cycle and complex III

Answer 36

Complex III has two Coenzyme Q binding sites

Question 37

Complex III has two Coenzyme Q binding sites, which one has a higher affinity for Q? QH2?

Answer 37

matrix side, Q shape site intermembrane side, QH2 shape

Question 38

net reaction of Qcycle

Answer 38

QH2 + 2 cyt c (ox) + 2H+(mat) -------Q + 2 cyt c (red) + 4H+(IM)

Question 39

electron transport in Q-cycle

Question 40

proton pumped out during Q-cycle

Question 41

does Q-cycle have 2 rounds?

Answer 41

yes

Question 42

Complex IV name

Answer 42

Cytochrome oxidase complex

Question 43

Cyanide and complex IV

Answer 43

Cyanide -CN, will harm complexIV

Question 44

Net ETC reaction: NADH(hint: every oxygen needs 4 electrons)

Answer 44

2NADH + O2 + 22H+(mat) ------- 2NAD+ + 2H2O + 20H+(IM)

Question 45

Complex II name

Answer 45

succinate dehydrogenase succinate + Q----> fumarate + QH2

Question 46

proton pumped after succinate dehydrogenase?

Answer 46

0

Question 47

Net ETC reaction of QH2

Answer 47

2QH2 + O2 + 12H+(mat)------> 2Q + 2H2O + 12H+(IM)

Question 48

summary of proton pump, per NADH and per QH2

Answer 48

Oxidation of 1 matrix NADH pumps 10 protons; oxidation of QH2 pumps 6

Question 49

Proton gradient from electron transport

Answer 49

Matrix pH ~ 7.9 intermembrane space pH~ 7.2=

Question 50

Net reaction of mammalian ATP synthase

Answer 50

2⅔ protons per ATP moved into matrix

Question 51

where's ATP made in mitochondria

Answer 51

matrix

Question 52

Movement of ADP, Pi and ATP

Question 53

1 NADH allows synthesis and export of _____ ATP

Answer 53

2.5

Question 54

why 1 NADH could allow synthesis and export of 2.5 ATP

Answer 54

ATP synthesis needs 3 H+,ADP, Pi transport in and ATP out needs 1 H+, finally, 1NADH could move out 10 H+

Question 55

1 QH2 allows synthesis and export of ___ ATP

Answer 55

1.5

Question 56

why 1 QH2 allow synthesis and export of 1.5 ATP

Answer 56

ATP synthesis needs 3 H+,ADP, Pi transport in and ATP out needs 1 H+, finally, 1QH2 could move out 6 H+

Question 57

total ATP genesis from glucose to CO2

Answer 57

32 ATP equivalents

Question 58

ATP genesis during glycolysis

Answer 58

7 (2.5*2, +2)

Question 59

ATP genesis during pyruvate processing

Answer 59

5(2.5*2)+2CO2

Question 60

ATP equivalents produced in cirtric acid cycle

Answer 60

20 (2.5*6, +1.5*2,+2GTP)

Question 61

ATP synthase structure

Answer 61

F1Fo

Question 62

embeded structure of ATP synthase

Answer 62

Fo