Urease

Description

Urease is found in the natural environment (water and soil) and in human body, where its occurrence is connected with protein degradation. It is an enzyme and is capable of urea hydrolysis: one molecule of ammonia and one molecule of carbamate appear in the first step, carbamate spontaneously converts into the second ammonia molecule and carbonic acid in a water solution, and ammonia is protonated. This urea hydrolysis results in pH increase. Urease and ammonia, generated during urea hydrolysis, may be toxic for human tissue and probably have role in long-lasting diseases, like atherosclerosis, urinary tract infections, or rheumatoid arthritis.
Urease can be used to analyze urea concentration in blood, urine, alcoholic beverages, natural water and environmental wastewaters; to analyze heavy metal content in natural waters, wastewaters and soil; to determine creatinine, arginine and IgG;  to remove urea from artificial kidney dialyzates, alcohol beverages and fertilizer wastewaters; to control or shift pH for multi-enzyme reaction system; to hydrolyze urea as sources of ammonia or carbon dioxide in special cases, and for the wastewater reclamation for life support systems in space.

References

[1] Iwona Konieczna, Paulina ?arnowiec, Marek Kwinkowski, Beata Kolesińska, Justyna Fr?czyk, Zbigniew Kamiński, Wies?aw Kaca (2012) Bacterial Urease and its Role in Long-Lasting Human Diseases, Curr Protein Petp Sci., 13, 789-806
[2] Yingjie Qin, Joaquim M. S. Cabral (2002) Review: Properties and Applications of Urease, Biocatalysis and Biotransformation, 20, 1-14

Chemical Properties

powder

Uses

Urease from Canavalia ensiformis may be used for urea determination of various samples, such as legumes. It may be useful for the detection of pathogens as well as heavy-metal ions.

Uses

Urease from Canavalia ensiformis may be used for urea determination of various samples, such as legumes . It may be useful for the detection of pathogens as well as heavy-metal ions.

Uses

Clinical reagent in determination of urea in body fluid.

General Description

Subunit molecular weight: ~90,770
Composed of six subunits with total molecular weight: ~544,620

Agricultural Uses

Urease, an enzyme, converts urea into ammonium carbonate [(NH₄)₂CO₃] that releases ammonia. Thus, the enzyme activates the hydrolysis of urea. When the release occurs on or near the soil surface, ammonia is lost to the air; if it occurs near the seeds, they fail to germinate, or it proves to be toxic to the roots of young saplings. Crops can get affected by a high concentration of ammonia. Soybean, jack beans and a number of fungi are sources of urease. Its isoelectric point is pH 5.5.
Urease enzyme catalyzes the hydrolysis of urea which occurs readily in the soils. Large numbers of bacteria, fungi and actinomycetes in soils possess urease. A small group of bacteria, known as urea bacteria, have an exceptional ability to decompose urea. Activity increases in proportion with the size of the soil microbial population and the organic matter content. The presence of relatively fresh plant residues often results in abundant supplies of urease. The greatest activity of urease is reported to occur in the rhizosphere, where microbial activity is high and where it can be excreted from the plant roots.
Although warm temperature (up to 37°C) favors urease activity, the hydrolysis of urea occurs at significant rates at temperatures down to 2°C. The effects of soil moisture levels on urease activity are generally small in comparison to the influence of the pH and temperature. Free ammonia inhibits the enzymatic action of urease.

Biochem/physiol Actions

Urease catalyzes the hydrolysis of urea into carbon dioxide and ammonia. Urease is involved in nitrogen metabolism and urea degradation. Urease from Canavalia ensiformis binds 2 nickel ions per subunit .