Bacteria use urease for survival in acidic environments by:
Survival in strongly acidic niches such as stomach lumen colonized by Helicobacter pylori causing gastritis and ulcer disease requires exceptionally efficient neutralization of extreme acidity. Urease is extraordinarily active nickel-dependent metalloenzyme encoded by ureABIEFGH operon containing structural subunits UreA and UreB plus accessory proteins UreE, UreF, UreG, UreD for nickel insertion, hydrolyzing urea abundant in gastric juice and urine into two molecules of ammonia and one carbon dioxide. Ammonia immediately protonates to ammonium NH4+ consuming protons and raising local pH from
Ref: Madigan et al., Brock Biology of Microorganisms, 16th ed., Chapter 6: Urease and Acid Survival via Ammonia Production.