Lecture 7 TCA cycle

Question 1

TCA cycle

Answer 1

Crucial for energy production. Acetyl CoA = startingpoint. Acetyl CoA can also be used in synthesis of other molecules.

Question 2

Citric acid cycle

Answer 2

TCA will give you citrate, could give you glutamate, could give you perferin (helps synthesize oxygen carrying molecule), malate (converted to carb).

Question 3

TCA cycle location

Answer 3

The TCA cycle is located in the mitochondrial matrix

Question 4

Isocitrate Dehydrogenase

Answer 4

First oxidative enzyme that gives you energy. Kick out CO2, transfer hydrogen to NAD to form NADH for electron transfer chain. Produces alpha ketoglutarate

Question 5

Succinyl-CoA

Answer 5

Similar to pyruvate dehydrogenase method. Kicks out CO2, forms NADH+H+. Going from this to Succinate produces 1 GTP.

Question 6

Malate

Answer 6

4 carbon molecule, ready to be oxidized again to malate dehydrogenase.

Question 7

Know all 4 dehydrogenase

Answer 7

Burn energy each time you use this. Add enzymes Some of these will take CO2 out, but all take out hydrogen.

Question 8

Alpha ketoglutarate dehydrogenase complex

Answer 8

Produces succinyl coA

Question 9

Succinate Dehydrogenase

Answer 9

Succinate to Fumerate. Forms FADH2 from FAD

Question 10

Fumerase

Answer 10

Add HOH to fumerate, forms malate to be ready for further oxidation.

Question 11

Malate dehydrogenase

Answer 11

L-malate to oxaloacetate - NAD to NADH + H

Question 12

Energetics of Glycolysis and CAC

Answer 12

Net gain of 30 to 32. G3PDH can produce either 3 or 5, hence difference. Complete breakdown of 1 glucose through glycolysis, TCA cycle, electron transfer will give 30-32 ATP.

Question 13

Regulation

Answer 13

Pyruvate dehydrogenase complex - contains 3 different enzymes. Controlled by pyruvate dehydrogenase kinase, PDH phosphatase reverses this (need this for insulin, when blood glucose is high).