Urease is an enzyme containing nickel, which increases the rate of hydrolysis of urea by ca. 1014 times.
In this reaction, urea is converted to ammonia (NH3) and carbon dioxide (CO2).
Urease has three identical subunits. One of these units is shown in the picture.
Each subunit has an active site with two coordinated Ni2+ ions.
These ions are coordinated to the molecule by the heteroatoms of the amino acids.
Molecule section with active site