The aim of this work was to study the significance of the urease enzyme in promoting Helicobacter pylori survival in various environments. A urease-positive H. pylori isolate, strain N6, and an isogenic urease-negative strain, strain N6(ureB::TnKm), were incubated in phosphate-buffered saline at a pH ranging from 2.2 to 7.2 for 60 min at 37 degrees C in both the presence and the absence of 10 m...

In this work, a glutathione (GSH) modified gold microelectrode was used for the covalent immobilization of urease biomolecules via the glutaraldehyde-coupling agent. The self-assembled monolayers (SAMs) onto the gold surface was investigated by using the electrochemical impedance spectroscopy measurements (EIS). Before urease grafting, a significant interaction was noticed between urea and the ...

Urea is generated in humans following the breakdown of amino acids and is evenly distributed throughout the body, including in the central nervous system, subcutaneous adipose tissue, blood serum, and epithelial lining fluid [1,2]. Various pathogenic microbes are able to utilise urea as a nitrogen source through the activity of the enzyme urease that converts urea into ammonia and carbamic acid...

Diazinon [O,O-diethyl O-2-isopropyl-6-methyl(pyrimidine-4-yl) phosphorothioate] and imidacloprid [1-(1-[6-chloro-3-pyridinyl]methyl)-N-nitro-2-imidazolidinimine] are applied to lawns for insect control simultaneously with nitrogenous fertilizers such as urea, but their potential effect on urease activity and nitrogen availability in turfgrass management has not been evaluated. Urease activity i...

Urea inglucose solutions has been advanced as a chemotherapeutic agent in sickle cell disease because it has been found effective both in reversing and in blocking sickling. It has been suggested recently that this beneficial action of urea may be the result of formation of cyanate from urea and subsequent carbamylation of beta S globin chains in the hemoglobin S molecule. In this paper, we sho...

The acid mine drainage (AMD) in Carnoulès (France) is characterized by the presence of toxic metals such as arsenic. Several bacterial strains belonging to the Thiomonas genus, which were isolated from this AMD, are able to withstand these conditions. Their genomes carry several genomic islands (GEIs), which are known to be potentially advantageous in some particular ecological niches. This stu...

abstract the addition of manures and chemical fertilizers as soil amendments for the improvement of soil fertility and quality could affect the seasonal changes in the activity of soil microbes and enzymes. this study aimed at investigating the effect of different levels of nitrogen from broiler litter and urea sources on the trend of urease, alkaline phosphatase and saccharase activities in a ...

Arginase of the Helicobacter pylori urea cycle hydrolyzes L-arginine to L-ornithine and urea. H. pylori urease hydrolyzes urea to carbon dioxide and ammonium, which neutralizes acid. Both enzymes are involved in H. pylori nitrogen metabolism. The roles of arginase in the physiology of H. pylori were investigated in vitro and in vivo, since arginase in H. pylori is metabolically upstream of urea...

The experiments described in this paper were undertaken to throw light on the possible role of gastric urease in the secretion of hydrochloric acid by the stomach. Mathews (1925) first suggested thatgastric hydrochloric acid might be produced by the reaction NJEI4Cl-NH3+HCl, and Luck (1924) showed that ammonia can be formed from urea by suspensions of ground dog gastric mucosa. Rigoni (1930), M...

Two experiments were conducted with growing male rats to determine the effects of 120 ppm of dietary sarsaponin (S) on nitrogen (N) metabolism when urea or protein are added to the diet. Growth, feed efficiency, N digestibility and balance, urinary N and ammonia-N (NH3-N), and cecal urease and NH3-N were measured. Growth and feed utilization were unaffected by dietary S. Adding urea or protein ...