Bridging Step of Krebs Cycle oxidatiion or reduction?

[jenzao]

Bridging Step of Krebs Cycle...oxidatiion or reduction?

I am told that the following reaction is a oxidative decarboxylation:

pyruvate +CoA + NAD+ ---> acetyl CoA + CO2 + NADH

but NAD+ is reduced to form NADH...

Do we call it an oxidation because we are interested in what happens to the pyruvate or am i missing something?

 

[Ygggdrasil]

In any redox reaction, one species will be reduced while the other will be oxidized. So, you are absolutely correct that this reaction results in the oxidation of pyruvate and the reduction of NAD⁺. It is called an oxidation because in glycolysis, we are interested in what happens to the original molecule of glucose that gets consumed by the cell. NAD⁺ is just considered a cofactor that helps the reaction along, despite the important role it plays in energy generation in the electron transport chain.

 

[Blueshift5]

The Bridging Step of the Krebs Cycle involves the conversion of pyruvate to acetyl CoA, which is a crucial step in the process of cellular respiration. This step can be considered both an oxidation and a reduction, as it involves the removal of a carbon atom from pyruvate (oxidation) and the transfer of electrons to NAD+ to form NADH (reduction).

In terms of the overall reaction, the focus is on the production of acetyl CoA and the reduction of NAD+, so it is commonly referred to as an oxidative decarboxylation. However, it is important to recognize that both oxidation and reduction occur simultaneously in this reaction.

Overall, the Bridging Step of the Krebs Cycle is a complex process involving multiple reactions and interdependent steps. It is essential for the efficient production of ATP and provides a deeper understanding of the biochemical pathways involved in cellular respiration.