What effect do organisms that produce urease have on the medium?

Organisms that produce urease can hydrolyze urea to ammonia (NH3) and carbon dioxide (CO2). This process is significant because urease catalyzes the breakdown of urea, resulting in the formation of ammonia, which in solution forms ammonium hydroxide (NH4OH). The reaction leads to an increase in pH due to the basic nature of ammonia, making the medium alkaline.

This alteration in pH is pivotal in defining the growth characteristics of urease-positive organisms. As ammonia accumulates, it increases the alkalinity of the medium, which is directly reflected in the changes observed during microbiological tests designed to identify urease activity. Understanding this reaction helps in diagnosing infections caused by urease-producing bacteria, such as Helicobacter pylori and various urea-positive enteric bacteria.