Lecture3

Question 1

Sources of Reactive Oxygen Species in complex1

Answer 1

Complex I:
• High NADH/NAD+ ratio
• High CoQH2/CoQ ratio and high Δp

Question 2

What will happen if in complex1 become Sources of Reactive Oxygen Species?

Answer 2

Hypoxic conditions, ATP synthase block

Question 3

When Complex3 will become signifiant effect on Sources of Reactive Oxygen Species?

Answer 3

Significant when treated with Antimycin A

Question 4

say the Lines of defense against ROS production.

Answer 4

1. Protein architecture prevents flow of
electrons to wrong acceptors
• Supercomplexes are thought to prevent
ROS production
2. Regulation of Energy metabolism
• Prevention of high Δp and NADH/NAD
ratios
3. Scavenging of ROS

Question 5

How ATP-producing pathways works?

Answer 5

ATP and NADH inhibit pathways

ADP and NAD activate them

Question 6

What are the Defense against reactive Oxygen Species?

Answer 6

1)Superoxide dismutase (Mitochondrial)
2 O•- 2 + 2H+ --->H2O2 + O2
2)Glutathion peroxidase (Mitochondrial)
2GSH + H2O2 -->GS–SG + 2H2O
3)Catalase (Peroxisomal)
2 H2O2 -->2 H2O + O2

Question 7

How is the reaction of Superoxide dismutase ? and where it took place?

Answer 7

Superoxide dismutase (Mitochondrial)
2 O•- 2 + 2H+ --->H2O2 + O2

Question 8

How is the reaction of Glutathion peroxidase ? and where it took place?

Answer 8

Glutathion peroxidase (Mitochondrial)
2GSH + H2O2 -->GS–SG + 2H2O

Question 9

How is the reaction of Catalase? and where it took place?

Answer 9

Catalase (Peroxisomal)

2 H2O2 –>2 H2O + O2

Question 10

How can you figure out where
the respiratory chain is
localized?

Answer 10

Immunogold labelling

- Localizing proteins by electron microscopy

Question 11

What is Core1?

Answer 11

Core1 - subunit of complex III

Question 12

OXPHOS is predominantly localized to the…..

Answer 12

cristae

Question 13

What are the protein import of mtDNA?

Answer 13

Mrpl36, Oxa1

Question 14

OXPHOS complexes are enriched in cristae The same is not true for mammalian cells.
T or F?

Answer 14

F, The same is true for mammalian cells

Question 15

What is TALM?

Answer 15

it a form of localization microscopy

Question 16

What is Accuracy in Localization Microscopy?

Answer 16

Accuracy in the range of 10 nm

Question 17

What are Prerequisites for TALM?

Answer 17

• Photostable fluorophores

* Substoichiometric labeling

Question 18

What is The HaloTag?

Answer 18

Labeling proteins with bright fluorophores -
• Small bacterial enzyme
(Dehalogenase)
• Reacts with chloroalkane in an
irreversible reaction

Question 19

Tim11 and Su g are essential for ATP-synthesis dimer formation, but not for enzymatic activity.
True or false?

Answer 19

True

Question 20

The ATP synthase forms ribbons of dimers only in yeast?

Answer 20

No also other species

Question 21

Do ATP synthase bend membranes?

Answer 21

Yes,ATP synthase and the bending of membranes