H. Nakamura et al., UREASE PLAYS AN IMPORTANT ROLE IN THE CHEMOTACTIC MOTILITY OF HELICOBACTER-PYLORI IN A VISCOUS ENVIRONMENT, Infection and immunity, 66(10), 1998, pp. 4832-4837
Helicobacter pylori exhibits chemotactic responses to urea, flurofamid
e, acetohydroxamic acid, and sodium bicarbonate, In buffer, the chemot
actic activities of a urease-positive strain were higher than those of
the isogenic urease-negative strain, Moreover, the chemotactic activi
ties of the urease-positive strain mere increased in a viscous solutio
n containing 3% polyvinylpyrrolidone, whereas those of the urease-nega
tive mutant were not. These results are in accordance with the fact th
at the mutant strain did not show swarming in motility agar regardless
of having flagella, Incubation of the wild-type strain with flurofami
de resulted in partial inhibition of the chemotactic activities in the
viscous solution, In addition, incubation with acetohydroxamic acid,
a low-molecular-weight, diffusible urease inhibitor, resulted in compl
ete loss of chemotactic activity in the viscous solution. The inhibiti
on of the chemotactic activity bg urease inhibitors paralleled the inh
ibition of urease, The chemotactic activity of H. pylori was also inhi
bited by the proton carrier carbonyl cyanide m-chlorophenylhydrazone,
showing that H. pylori utilizes proton motive force for motility, Thes
e results indicate that cytoplasmic urease plays an important role in
the chemotactic motility of H, pylori under a condition that mimics th
e ecological niche of the bacterium, the gastric mucous layer.