Suppression of polyglucose degradation inFusobacterium nucleatumATCC 10953 by amino acids

When supplied with a fermentable amino acid (glutamate, lysine or histidine), cells of Fusobacterium nucleatum ATCC 10953 formed an intracellular polymer from both glucose and galactose. Under anaerobic conditions the endogenous polymer (polyglucose) was fermented to a mixture of lactic, formic, acetic and butyric acids. Autoradiographic analysis of intracellular metabolites showed that the [14C]-labeled polymer(s) were metabolized via the Embden-Meyerhof pathway. Addition of glutamic acid, lysine or histadine to the anaerobic cell suspension inhibited polymer degradation, but these amino acids did not prevent the dissimilation of polymer by aerobic organisms.