Baicalin (BA) is the principal component of Radix Scutellariae responsible for its pharmacological activity. In this study, kinetics and mechanism of inhibition by BA against jack-bean urease were investigated for its therapeutic potential. It was revealed that the IC₅₀ of BA against jack-bean urease was 2.74 ± 0.51 mM, which was proved to be a competitive and concentration-dependent inhibition...

Urease catalyzes the hydrolysis of urea to ammonia and carbon dioxide. The ammonia (nitrogen (N) product of urease activity) is incorporated into organic compounds. Thus, urease is involved in N remobilization, as well as in primary N assimilation. Two urease isoforms have been described for soybean: the embryo-specific, encoded by the Eu1 gene, and the ubiquitous urease, encoded by Eu4. A thir...

Yersinia enterocolitica serotype O:3 and O:8 urease-negative mutants unable to express the 19-kDa beta subunit of urease were constructed and tested for virulence and arthritogenicity. Our results indicate that urease is needed for full virulence in oral infections and that it is not an arthritogenic factor in the rat model.

UNLABELLED A novel mechanism aimed at controlling urease expression in Helicobacter pylori in the presence of ample nickel is described. Higher urease activities were observed in an hp0868 mutant (than in the wild type) in cells supplemented with nickel, suggesting that the HP0868 protein (herein named Mua for modulator of urease activity) represses urease activity when nickel concentrations ar...

Optimizing nitrogen (N) availability to plants is crucial for achieving maximum crop yield and quality. However, ensuring the appropriate supply of N crops challenging due various pathways through which can be lost, such as ammonia (NH3) volatilization, nitrous oxide emissions, denitrification, nitrate (NO3−) leaching, runoff. Additionally, become immobilized by soil minerals when ammonium (NH4...

The Helicobacter pylori ureE gene product was previously shown to be required for urease expression, but its characteristics and role have not been determined. The UreE protein has now been overexpressed in Escherichia coli, purified, and characterized, and three altered versions were expressed to address a nickel-sequestering role of UreE. Purified UreE formed a dimer in solution and was capab...

BACKGROUND Rapid urease tests for Helicobacter pylori have a sensitivity of 80% to 90%. Therefore histologic examination of gastric biopsies is recommended as a "backup" diagnostic test in rapid urease test-negative patients. However, noninvasive tests (urea breath test, serology, whole blood antibody tests) may provide a more rapid diagnosis and be less expensive but offer similar accuracy. ...

The influence of urease activity on N distribution and losses after foliar urea application was investigated using wild-type and transgenic potato (Solanum tuberosum cv Désirée) plants in which urease activity was down-regulated. A good correlation between urease activity and N urea metabolism (NH3 accumulation) was found. The general accumulation of ammonium in leaves treated with urea indicat...

Urease from jack bean meal and hydrated seeds has been obtained in 25 to 33% yield with specific activity in the range of 1000 to 1070 units/mg protein. A purification of 100 to 130-fold was achieved from meal and fully soaked seeds. Use of beta-mercaptoethanol and EDTA was found essential to obtain this high yield and purity. Amino acid analysis showed all 18 amino acids commonly found in prot...

Mutation at either of two genetic loci (Eu2 or Eu3) in soybean (Glycine max [L.] Merr.) results in a pleiotropic elimination of the activity of both major urease isozymes. Surprisingly, the phenotype of a phylloplane bacterium, Methylobacterium mesophilicum, living on the leaves of eu2/eu2 or eu3-e1/eu3-e1 mutants is also affected by these plant mutations. The bacteria isolated from leaves of t...