How Many ATP is Equal to NADH

Introduction

In prokaryotes, the 3 ATP molecules are equal to 1 NADH molecule, inside the mitochondria. The ATP stands for Adenosine Triphosphate. It is the major energy currency of a cell. It is a high-energy molecule that transports and stores energy within cells. The NADH stands for Nicotinamide Adenine Dinucleotide. It occurs naturally inside the body and plays a vital role in producing energy.

Whereas in Eukaryotes, the 2-3 ATP molecules are equal to 1 NADH molecule, it is for each electron pair, is redirected to the Electron Transport Chain.

Main Content

Theoretically, during aerobic respiration, the maximum supply of ATP for the oxidation of 1 molecule of glucose is 38.

For Aerobic Respiration, it is highly complex to determine the exact yield of the ATP by following several reasons. It is because, the number of ATP molecules generated for producing a molecule of NADH, is not necessarily a whole number always.

In contrast to prokaryotes, eukaryotic cells produce NADH within the cytoplasm, which must be transferred across the mitochondrial membrane during glycolysis. This process occurs before it can transport electrons to the Electron Transport Chain, which requires energy. As an output, only 1-2 ATP molecules are produced from this NADH.

However, based on the theoretical maximum supply of ATP for one molecule of glucose that is oxidised by aerobic respiration, only three ATP will be produced for every pair of electrons that one molecule of NADH directs to the electron transport chain.

Conceptually, in prokaryotes, the total maximum number of ATP produced per Glucose is 38 ATP. Out of which, 34 were from Oxidative Phosphorylation, and 4 were from Substrate-level Phosphorylation.

The ATP rendered by NADH is as follows:

Transition Reaction: 6 ATP produced by 2 NADH

Glycolysis: 6 ATP produced by 2 NADH, on Oxidative Phosphorylation

Citric Acid Cycle: 18 ATP produced by 6 NADH, by Oxidative Phosphorylation

In eukaryotic cells, the theoretical maximum amount of ATP produced per unit of glucose varies between 36 and 38, depending on how 2 NADH is produced in the cytoplasm during glycolysis and how it enters the mitochondria. In the end, either 2 or 3 ATP are produced for every 1 NADH.

Hence, inside the mitochondria, the 3 ATP is equivalent to one molecule of NADH, whereas, in the cytoplasm, the 2 ATP is equivalent to one molecule of NADH.

Conclusion

It has been determined that NADH, which is produced inside the cytoplasm during glycolysis, must cross the mitochondrial membrane before it can transfer electrons to the electron transport chain because it needs a lot of energy. Additionally, the amount of ATP produced by prokaryotes and eukaryotes can vary.