Fermentation

Definition

Fermentation is an anaerobic catabolism of a reduced carbon source (e.g., glucose) to generate ATP within a strict internal oxidation-reduction balance. In many cases, the same substrate is used both as reductant and oxidant. The hallmark of fermentation is the accumulation of partially oxidized end products. Only a part of the chemical energy stored in the initial substrate is conserved during the synthesis of ATP, usually by a mechanism of substrate-level phosphorylation. Nevertheless, there are some examples of the involvement of an electrochemical ion gradient in the synthesis of ATP (e.g., citrate fermentation).

History

Antoine Laurent Lavoisier (1743–1794) collected the first quantitative data on alcoholic fermentation. Louis Pasteur (1822–1895) studied in depth the fermentation by intact living cells and defined this physiological process as “life without oxygen.” In 1897, Eduard Buchner (1860–1917) showed that fermentation could occur in cell-free extracts,...