Pasteur Effect

Pasteur effect [pa′stər i‚fekt]

(microbiology)

Inhibition of fermentation by supplying an abundance of oxygen to replace anerobic conditions.

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Pasteur Effect 

a slowing or complete cessation of alcoholic fermentation in the presence of oxygen; first observed by L. Pasteur. The effect also occurs in animals and plant tissues, where O₂ inhibits anaerobic glycolysis.

The Pasteur effect involves the transition from anaerobic glycolysis (fermentation) to respiration (the consumption of O₂) in the presence of O₂, and its significance lies in the fact that the cells switch to a more economical mode of obtaining energy. For a given substrate, approximately 20 times as much energy is extracted during respiration as during fermentation. As a result, the rate of utilization of the substrate, for example, glucose, decreases in the presence of O₂. The molecular mechanism of the Pasteur effect apparently consists in the competition between respiration and fermentative glycolysis for adenosine disphosphate (ADP), which is used to form adenosine triphosphate (ATP).

REFERENCES

Biokhimiia rastenii. Moscow, 1968. Chapter 10. (Translated from English.)
Schlegel, H. Obshchaia mikrobiologiia. Moscow, 1972. Chapter 8. (Translated from German.)