Bafilomycin A1 inhibits Helicobacter pylori-induced vacuolization of HeLa cells.
Bafilomycin A1, a specific inhibitor of the vacuolar-type H(+)-ATPase, responsible for acidification of intracellular compartments, prevents the vacuolization of Hela cells induced by H. pylori, with an inhibitory concentration giving 50% of maximal (ID50) of 4 nM. Bafilomycin A1 is also very efficient in restoring vacuolated cells to a normal appearance. The vacuolating activity of Helicobacter pylori is not inhibited by a series of specific inhibitors of vacuolar H(+)-ATPases. These findings indicate that a transmembrane pH gradient is needed for the formation and growth of vacuoles caused by the bacterium and that this pH gradient is due to the activity of a vacuolar ATPase proton pump of HeLa cells.
Papini
E
E
Dipartimento di Scienze Biomediche, Università di Padova, Italy.
Bugnoli
M
M
De Bernard
M
M
Figura
N
N
Rappuoli
R
R
Montecucco
C
C
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D006367:HeLa Cells / Q000187:drug effects / Q000382:microbiology* / Q000648:ultrastructure; D016480:Helicobacter pylori / Q000472:pathogenicity / Q000502:physiology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007424:Intracellular Fluid / Q000737:chemistry; D018942:Macrolides; D017494:Proton Pumps / Q000187:drug effects*; D006180:Proton-Translocating ATPases / Q000037:antagonists & inhibitors*; D014617:Vacuoles / Q000201:enzymology*; D014774:Virulence
D000900:Anti-Bacterial Agents; D018942:Macrolides; D017494:Proton Pumps; C040929:bafilomycin A1; D006180:Proton-Translocating ATPases