Electron Transport Chain

Front 1

Permeability of inner membrane

Back 1

Only to H20, CO2, and O2. Not NADH. Shuttles required

Front 2

Mal-Asp shuttle

Back 2

Uses NADH only.

Oxaloacetate becomes aspart and ak, which go to cyt. Asp. becomes oxaloacetate, then malate at cost of, and then it goes back in. Then malate becomes oxaloacetate, which releases NADH into mitochondria.

Front 3

Glycerol Phosphate shuttle

Back 3

Dhap converts into Gap, which costs NADH. Then GAP converts to DHAP, done by G3P. The dehydrogenase complex for this has FAD inside, and it becomes FADH to during this conversion.

Front 4

Other molecules transported:

Back 4

ADP-ATP translocators send ATP out to get ADP into the matrix.

Phosphate transported in via the PO4/H gradient

Front 5

Cofactors and Prosthetic groups

Back 5

NADH, FADH2, Coenzyme Q, Iron Sulfur, Cytochromes (Heme)

Front 6

NADH as cofactor

Back 6

Water soluble, carries 2 electrons

Front 7

FADH2

Back 7

Water soluble, carries 1-2 electrons

Front 8

Coenzyme Q

Back 8

Free lipid soluble, carries 1 to 2, incomplete reduction can lead to free radicals

Front 9

Iron-Sulfur

Back 9

Protein bound carrier. Carries 1 electron. Sulfur binds, iron stabilizes.

Front 10

Cytochromes

Back 10

Protein bound electron carriers, contain heme, which is large porphyrin ring. 1 Electron transferred, present in inner mit. membrane.

Four types: B, C1, C, AA3

Front 11

Redox Potential

Back 11

When half molecules are reduced, half oxidized. Electrons pass freely from low redox to high redox.

Front 12

Complex 1

Back 12

(NADH-Coenzyme Q oxidoreductase)

FMN takes electrons from NADH, transfers to Fe-S, gives them to CoQ.

Protons move from matrix to IMS.

Front 13

Complex 2

Back 13

(Succinate-CoQ oxidoreductase)

No proton transfer occurs here, part of TCA. Electrons come from succinate bound to FADH2, go to FeS clusters, given to Coenzyme Q.

Front 14

Complex 3

Back 14

Contains cytochrome b, c1, and one fes protein. Pumps hydrogen from the matrix to the intermembrane space, moving an electron from the Q to the Cytochrome c.

Front 15

Q pool

Back 15

Q pool explains how a cytochrome has two electrons but moves one at a time. One will be transferred out with two hydrogens, but one will cycle into the Q pool, and then be released with two protons in the next cycle.

Front 16

Complex 4

Back 16

(Cytochrome oxidase)

Contains cytochromes a and a3. Electrons move from cytochome c into copper ions, to a and a3, then another copper ion, and finally into oxygen, causing water to be produced.

Front 17

Oxidative Phosphorylation

Back 17

The energy released during each electron transfer is used to pump out proteins from matrix into ims. Complexes 1 3 and 4 will move H from membrane to space, while 5 will move them from space out. Note 2 does not do this at all.

Front 18

Complex 5

Back 18

Drives phosphorylation of ADP to ATP. 2.5 ATP per NADH and 1.5 ATP per FADH2. Made up of the rotor and the peripheral membrane. The peripheral membrane is water soluble, and what makes the ATP.

Front 19

Rotary engine and ADP/ATP

Back 19

Has three sites: L, T, and O.

When rotated to L, ADP and Pi enter and are ready for synthesis. With energy,

Front 20

Site-specific inhibitors for Complex 1

Back 20

Rotenone and Amytal

Front 21

Site-specific inhibitors for complex 3

Back 21

Antimycin A

Front 22

Site-specific inhibitors for complex 4

Back 22

Carbon monoxide, Cyanide, and Sodium Azide

Front 23

Phosphorylation inhibitors

Back 23

Oligomycin, blocks Fo (the rotor)

Front 24

Uncouplers

Back 24

DNP, FCCP will both uncouple the proton gradient.

Front 25

DNP uncouplers effect

Back 25

Increases the permeability of the inner mitochondrial membrane to H. ETC will work harder because of the decrease in PMF. This is why DNP was a diet pill.

Front 26

Brown Adipose Tissue

Back 26

Newborn mammals that lack fur such as humans contain brown fat in neck and upper back. Generates heat by uncoupling via a protein called thermogenin.

Front 27

Disadvantage of Aerobic Metabolism

Back 27

Produces reactive oxygen species

Superoxides, Hydrogen peroxide, and Hydroxyl radical.

Front 28

Antioxidant mechanisms

Back 28

Biological enzymes that help neutralize free radicals.

Superoxide dismutase, catalase, and glutathione peroxidase