The metabolism of pyruvate by Helicobacter pylori was investigated emp
loying one- and two-dimensional H-1 and C-13 nuclear magnetic resonanc
e spectroscopy. Generation of pyruvate from L-serine in incubations wi
th whole cell lysates indicated the presence of serine dehydratase act
ivity in the bacterium. Pyruvate was formed also in cell suspensions a
nd lysates from phosphoenol pyruvate. Metabolically competent cells in
cubated aerobically with pyruvate yielded alanine, lactate, acetate, f
ormate, and succinate. The production of alanine and lactate indicated
the presence of alanine transaminase and lactate dehydrogenase activi
ties, respectively. Accumulation of acetate and formate as metabolic p
roducts provided evidence for the existence of a mixed-acid fermentati
on pathway in the microorganism. Formation of succinate suggested the
incorporation of the pyruvate carbon skeleton into the Kreb's cycle. A
ddition of pyruvate to various liquid culture media did not affect bac
terial growth or loss of viability. The variety of products formed usi
ng pyruvate as the sole substrate showed the important role of this me
tabolite in the energy metabolism of H. pylori.