Helicobacter pylori cytotoxic activity was significantly decreased by an asparaginase-deficient strain 31 while Mycobacterium tuberculosis exploits asparaginase to assimilate nitrogen to produce ammonium and resist acid stress during infection 33; Salmonellae asparaginases mediate virulence and inhibit T cell responses 34,35. The gene discussed is ASPG; the disease is infection.