20 Points On Krebs Cycle

1. It was discovered by Hans Adolf Krebs in 1930s.
2. Hans Adolf Krebs was awarded Nobel Prize for his work of Krebs Cycle.
3. It is also known as the citric cycle since citric acid is the 6 carbon molecule that initiates the Krebs cycle.
4. It takes place in mitochondria which is the energy generator for the cell, specifically it occurs at the matrix of mitochondria. 
5. It has 8 steps and each step is catalyzed by a specific enzyme.
6.  Overall chemical equation for the Krebs cycle: oxaloacetate + acetyl-CoA + ADP + Pi + 3NAD⁺ + FAD → CoA + ATP + 3NADH + 3H⁺ + FADH2 + 2CO2 + oxaloacetate
7. Oxaloacetate is the final product of the Krebs cycle then it goes back and combine with acetyl-Coa again to start a new cycle.
8. Acetyl-CoA is formed from pyruvate oxidation where a pyruvate molecule releases one carbon and oxidase by NAD+ then combine with the enzyme CoA. 
9. Acetyl- CoA (2C) enters the cycle releases CoA and combine with oxaloacetate(4C) to form citric acid (6C)
10. Citric acid(6C) undergoes isomerization to form isocitric(6C).
11. Isocitric(6C) converts into α-ketoglutarate (5C), one carbon and two hydrogen atoms are lost during the process which reduces NAD+ into NADH.
12.  α-ketoglutarate (5C) converts into succinyl-CoA (4C). A Carbon is lost, enzyme CoA is added, and two hydrogen atoms has reduced NAD+ into NADH.
13.  succinyl-CoA (4C) converts into succinate (4C).  Enzyme CoA has been released, GDP has reduced from the process in which then later oxidased by ADP in order to produce ATP. 
14. FADH 2 through the reduction from FAD+ during the conversion from Succinate(4C) to Fumarate (4C).
15. Fumarate(4C) converts into Malate (4C) by an addition of water. 
16. NADH is produced from the conversion from Malate(4C) to Oxaloacetate(4C).
17. Krebs cycle will occur twice since glycolysis can generate two pyruvates. 
18. Energy is produced in step 3.4.5.6 and 8.
19. NADH & FADH2 produced from the cycle will move into Electron Transport Chain in order to convert into ATP.
20. The carbon dioxides formed from the cycle will move out of the cell as metabolism wastes.