Oxidative Decarboxylation

Oxidative Decarboxylation

Oxidative DecarboxylationPyruvate is converted into acetyl-CoA in order to be

brought into the mitochondria.

Oxidative Decarboxylationrxn type: decarboxylation

redox

synthesis

enzyme: decarboxylase

dehydrogenase

synthase

energy: released

Coenzyme ACoenzyme A is a large

organic molecule.

The active functional group is a thiol.

It is also written as

CoA-SH.

Oxidative Decarboxylation Summary

1. 2 pyruvate 2 acetyl-CoA

2. 2 CO2 released

3. 2 NADH produced

Kreb Cycle

Krebs Cycle

Krebs Cycle Overview

Krebs cycle is a cyclical process to:

1. produce additional CO2 molecules

2. generate more high energy molecules (NADH, FADH2 and ATP)

Also known as the citric acid cycle and the tricarboxylic acid cycle (TCA).

Krebs Cycle

Krebs Cycle: Step by StepStep 1:join 2 carbon molecule

with a 4 carbon molecule

rxn type: synthesis

enzyme: synthase

energy: absorbed

Krebs Cycle: Step by StepStep 2:rearrangement of atoms

with the help of H2O

rxn type: isomerization

enzyme: isomerase

energy: equivalent

Krebs Cycle: Step by StepStep 3:synthesis of CO2 and

NADH

rxn type: decarboxylation

redox

enzyme: decarboxylase

dehydrogenase

energy: released

Krebs Cycle: Step by StepStep 4:CO2 release and energy

molecule formation

rxn type: decarboxylation

redox

synthesis

enzyme: decarboxylase

dehydrogenase

synthase

energy: released

Krebs Cycle: Step by StepStep 5:ADP phosphorylation to ATP

rxn type: substrate-level phosphorylation

cleavage

enzyme: kinase

lyase

energy: released

Krebs Cycle: Step by StepStep 6:FADH2 (energy molecule)

formation

rxn type: redox

enzyme: dehydrogenase

energy: released

FAD / FADH2

FAD – flavin adenine dinucleotide (oxidized form)

FADH2 – flavin adenine dinucleotide (reduced form)

Krebs Cycle: Step by StepStep 7:rearranging the

molecule for the next reaction

rxn type: hydration

enzyme: hydrase

energy: absorbed

Krebs Cycle: Step by StepStep 8:energy molecule

formation & recreating molecules for Krebs cycle

rxn type: redox

enzyme: dehydrogenase

energy: released

Krebs Cycle Summary1. two cycles of Krebs for EACH glucose molecule

2. acetyl-CoA oxaloacetate (per cycle)

3. 2 CO2 released (per cycle)

4. 3 NADH produced (per cycle)

5. 1 FADH2 produced (per cycle)

6. 1 ATP produced (per cycle)

Krebs Cycle: Big Picture Perspective

Many of the components of Krebs cycle are used in many other types of metabolic processes.