Comparative carbohydrate metabolism and a proposal for a phylogenetic relationship of the acetic acid bacteria.

The oxidation of 20 carbohydrates and derivatives by 45 strains of acetic acid bacteria, representing most of the known species, was studied and correlated with the enzymic constitution of the organisms. The strains of the mesoxydans group of Frateur and the acetate-oxidizing Gluconobacters oxidized the greatest variety of substrates and contained the most complex enzyme system. The strains investigated could be arranged in two main lines, each one with a stepwise decreasing gradation of oxidative properties. In contrast to the expectations evoked by their names, the strains of the ‘oxydans’ group had only limited oxidative powers and the ‘peroxydans ’ bacteria even less so. The enzymic mechanism of the catabolism of several carbohydrates was discussed. It is proposed to split the acetic acid bacteria into two biotypes : Glwconobacter oxydans and Acetobacter aceti, and to consider the existing species as varieties within the two main types, An approach to the phylogenetic interpretation of the intermediary carbohydrate catabolism of these bacteria is discussed.