[Monosaccharide composition of the exopolysaccharides of oligonitrophilic bacteria]

Exopolysaccharides from ten strains of oligonitrophilic bacteria were found to contain galactose, glucose and mannose. Strains belonging to the genus Mycobacterium contained also fucose, ramnose and three sugars that had not been identified: two of them were lipophilic and one had a lower Rf than ramnose. A correlation has been established between the composition of monosaccharides, their molar ratios in exocellular polysaccharides of oligonitrophilic bacteria, and the taxonomy of these microorganisms. Sporeforming bacteria belonging to the genus Bacillus produce polysaccharides which contain galactose, glucose and mannose at a ratio of 10:19: : (13--15). The molar ratio between the same sugars in exopolysaccharides of bacteria belonging to the genera Pseudomonas and Azotomonas is 10:(12--19) : (4--6). The ratio between galactose, glucose, mannose, fucose, ramnose, the unknown sugar and the sum of two lipophilic sugars in exocellular polysaccharides of the genus Mycobacterium is 10:(15--16) : (5--6) : (7--10) : (0.1--9) : (0.3--0.5) : (0.4--0.8).