The Aerobic Dissimilation of Lactic Acid by the Propionic Acid Bacteria.

The hydrogen reacts with lactic acid to form propionic acid. Pyruvic acid has been isolated from the fermentation of glucose (1934) and of lactic acid (unpublished data) by Wood and Werkman. These investigators supported Van Niel's proposed dissimilation of pyruvic acid inasmuch as the occurrence of acetaldehyde could not be demonstrated. Little information is available concerning the aerobic dissimilation of lactic acid. Virtanen (1923) found that aeration had slight influence on the fermentation while Van Niel reported a considerable increase in acetic acid when he employed vigorous aeration. As part of a general study of the respiration of the propionic