Ibuprofen affects arylamine N-acetyltransferase activity in Helicobacter pylori from peptic ulcer patients

Arylamine N-acetyltransferase (NAT) activities with 2-aminofluorene and p-aminobenzoic acid were determined in the bacterium Helicobacter pylori collected from peptic ulcer patients. Cytosols or suspensions of H. pylori with or without specific concentrations of ibuprofen co-treatment showed different percentages of 2-aminofluorene and p-aminobenzoic acid acetylation. The data indicate that there was decreased NAT activity associated with increased levels of ibuprofen in H. pylori cytosols. Inhibition of growth studies on H. pylori demonstrated that ibuprofen elicited a dose-dependent bactericide effect in H. pylori cultures, i.e. the greater the concentration of ibuprofen, the greater the inhibition of growth to H. pylori. For the cytosol and intact bacteria examinations, the apparent values of Km and Vmax were decreased after co-treatment with 40 microM ibuprofen. This report is the first demonstration of ibuprofen inhibition of arylamine N-acetyltransferase activity and ibuprofen inhibition of growth in the bacterium H. pylori.