TABLE 1

Urease activity of H. pylori wild-type, urease deletion, and site-directed mutant strains

StrainUrease activity (μmol/min/mg)a
43504 (wild type)4.65 ± 0.96a
ΔureAB strain0.06 ± 0.01
ureBH136A strain0.07 ± 0.02
ureBH138A strain0.07 ± 0.01
ureBK219A strain0.08 ± 0.01
  • a Urease activity expressed in micromoles of NH3 produced per minute per milligram of total protein. Results shown are the means ± SDs from 3 to 8 independent experiments with assays performed in triplicate.