The bacteria is positive for oxidase, catalase and urease. It produces oxidase, catalase, and urease. They are aerobic, catalase positive, urease positive, nonsporeformers. Using the enzyme urease, these organisms metabolize urea into ammonia and carbon dioxide. The organism is oxidase positive, but urease, nitrate reductase, and citrate negative. In the subsequent urease driven enzymatic reaction, urea is converted into carbon dioxide and ammonia. It is indole negative and urease negative. Nickel enzymes such as urease are considered virulence factors in some organisms. An exceptional urease is obtained from "Helicobacter" sp.. Similar to other "Yersinia" species, it tests negative for urease, lactose fermentation, and indole. It is urease and indole-negative. The presence of urease is used in the diagnosis of "Helicobacter" species. The binding of urea to the active site of urease has not been observed. For example, jack bean urease has two structural and one catalytic subunit. This is done by secreting copious amounts of urease through the cell membrane.