Anaerobic growth

Question 1

How is NADH recycled?

Answer 1

Pyruvate recycles NADH back to NAD+ to allow glycolysis to continue

Question 2

Describe the fermentation process as used by yeasts and most anaerobic bacteria

Answer 2

Pyruvate is converted to acetaldehyde using pyruvate decarboxylase with carbon dioxide leaving

Acetaldehyde is converted to ethanol using alcohol dehydrogenase and NADH + H+ is reduced to NAD+

Question 3

Describe the fermentation process as used by Salmonella and E. coli

Answer 3

Pyruvate + Coenzyme A is converted to acetyl CoA using pyruvate formate lyase and formic acid leaves

Acetyl CoA is converted to ethanol using alcohol dehydrogenase and 2NADH are reduced to 2NAD+