Urease production by Helicobacter (Campylobacter) pylori.

Urease activity of 50 Helicobacter pylori (H. pylori) strains was assessed employing a photometric assay. Urea hydrolysis reached a maximum in the late log-phase and during the plateau phase of bacterial growth. The reaction time of H. pylori urease was significantly shorter than that of other urease producing bacteria (P. mirabilis, P. vulgaris, K. pneumoniae, K. oxytoca). Increasing the reaction temperature hardly led to an acceleration of the quick urea hydrolysis of H. pylori, in contrast to the situation with P. mirabilis. Acetohydroxamic acid showed a dose-dependent non-competitive suppression of urease production, whereas 9 antibiotics in subinhibitory concentrations did not influence urease production of H. pylori.