Urease, a nickel-dependent metalloenzyme, is synthesized by a wide variety of
organisms, including plants, bacteria and fungi. It catalyzes the hydrolysis of urea into
ammonia and carbon dioxide. Although the amino acid sequences of plant and bacterial
ureases are closely related, some biological activities differ significantly. To date, the
structural information is available only for bacterial ureases although the enzyme extracted
from jack bean (Canavalia ensiformis), which is the best-studied plant urease, had been
crystallized in 1926. Tests for urease activity determination should be based on direct or
indirect methods and most of the methods utilized for urease detection are based on
analysis of its activity in urea hydrolysis. The urease activity determination is extremely
important in several areas, mainly in agriculture, medicine and clinical analysis.
Keywords: Urease, metalloenzyme, urea, ammonia, carbon dioxide, canavalia
ensiformis, virulence factors, colorimetric test, bromcresol purple, ficoll reagent,
nessler, alcalimetric test, pH changes, back-titration, agriculture, clinical test,
phenol red, pH indicator, spectrophotometry.
