Cellular Respiration: Pyruvate Oxidation

How much ATP is produced in pyruvate oxidation?

6 ATP??

What must happen before pyruvate oxidation occurs?

Pyruvate MUST enter the mitochondrion - crossing the inner membrane and arriving at the matrix.

What are the steps of pyruvate oxidation carried out by (enzyme)?

Pyruvate hydrogenase

Step 2

Remaining two carbon portion is oxidized by the NAD+. In the process, the NAD+ gains two hydrogen atoms (2 protons and 2 electrons) from organic molecules and the remaining 2-carbon compound becomes an acetic acid group.

Pyruvate oxidation is the next step in capturing the remaining _________ in the form of _____________

energy, ATP

What happens after pyruvate oxidation? (What happens to the molecules)

- The two molecules of acetyl-CoA enters the krebs cycle where additional free energy transfer occurs - Two molecules of NADH proceed to stage 4 to produce ATP by oxidative phosphorylation - Two CO2 molecules diffuse out of the mitochondrion and out of cell as low energy waste product - Two H+ ions dissolve in to the matrix

What is the equation for pyruvate oxidation?

2 pyruvate molecules + 2 NAD+ 2 CoA --> 2 acetyl CoA + 2 NADH + 2 H+ + 2 CO2

Step 1

A carboxyl group is removed [decarboxylation] off of the pyruvate and released as a molecule of CO2 leaving behind a 2-carbon molecule.

Step 3

A sulfur containing compound called coenzyme A (CoA) is attached to acetate component forming acetyl-CoA and this prepares the two carbon acetyl portion of the molecule for further oxidation in krebs

What is the purpose of Acetyl CoA

It serves as a fuel for the citric acid cycle in the next stage of cellular respiration.

Where does pyruvate oxidation take place?

Takes place in the mitochondrial matrix.

Where is the reaction transferred in step 2?

The reaction transfers potential energy to NAD+

Pyruvate molecules are produced by _______ in the ______________ but takes place in the ______________________ _________________

glycolysis, cytoplasm, mitochondrial matrix

What happens in pyruvate oxidation? [Overview]

two pyruvate molecules formed in glycolysis are transported through the two mitochondrial membranes in to the matrix