Existence of two alternative pathways for fructose and sorbitol metabolism in Bacillus subtilis Marburg.

Strains of Bacillus subtilis mutated for fructose phosphotransferase system (fruA), fructose-1-phosphate kinase (fruB), fructokinase (frucC) have been tested for their catabolism of sorbitol and fructose. It is shown that the previously known pathways of sorbitol and fructose degradation in B. subtilis, e.g.: (see article) may metabolize intracellular fructose produced either by sorbitol oxidation or by fructose-1-phosphate dephosphorylation. The intracellular fructore degradation via fructose-1-phosphate kinase has been found to require the fructose phosphotransferase system which ensures a vectorial transport of fructose.