Description Urease (EC 3.5.1.5) is an enzyme that catalyzes the hydrolysis of urea into carbon dioxide and ammonia. The reaction occurs as follows: (NH2)2CO + H2O = CO2 + 2NH3. In 1926 James Sumner showed that urease is a protein. Urease is found in bacteria, yeast and several higher plants. Characteristics: Active site metal: nickel(II); Molecular weight: 480 kDa or 545 kDa for Jack Bean Urease (calculated mass from the amino acid sequence); Optimum pH: 7.4; Optimum Temperature: 60 degrees Celsius; Enzymatic specificity: urea and hydroxyurea; Inhibitors: heavy metals. The multi-subunit enzyme usually has a 3:3 (alpha:beta) stoichiometry with a 2-fold symmetric structure (note that the image above gives the structure of the asymmetric unit, one third of the true biological assembly). An exceptional urease is found in Helicobacter pylori, which combines four of the regular six subunit enzymes in an overall tetrahedral assembly of 24 subunits (a12b12). This supra-molecular assembly is thought to confer additional stability for the enzyme in this organism, which functions to produce ammonia in order to neutralise gastric acid. The presence of urease is used in the diagnosis of Helicobacter species.
Source Escherichia Coli.
Physical Appearance Sterile Lyophilized Powder.
Formulation Each mg of protein contains 370µg Potassium Phosphate and 30µg EDTA Na2.
Solubility It is recommended to reconstitute the lyophilized Urease in sterile 18MΩ-cm H2O.
Stability Urease although stable at 4℃ for 3 weeks, should be stored desiccated below -18℃.
Please prevent freeze-thaw cycles.
Purity Greater than 95.0% as determined by:
(a) Analysis by RP-HPLC.
(b) Analysis by SDS-PAGE.
Biological Activity The activity was found to be 125U/mg powder.
Unit Definition One Unit oxidizes one micromole of NADH per minute at 25℃, at pH 7.6.
Usage CHI's products are furnished for LABORATORY RESEARCH USE ONLY. The product may not be used as drugs, agricultural or pesticidal products, food additives or household chemicals.