Jack bean urease: The effect of active-site binding inhibitors on the reactivity of enzyme thiol groups

Kinetic and Thermodynamic Behaviors of Soil Urease as Affected by Urease Inhibitors

“…It was shown from the above variations of Km and Vmax that the mechanism of HQ, PPD and NBPT on soil urease was all of mixed inhibition, beings not in accordance with the previous studies of PPD in a pure enzyme system (McCarty et al, 1990;Krajewska and Zaborska, 2007). Kumar and Wagenet (1984) and by Dalal (1975), but lower than those reported by other authors (Lai and Tabatabai, 1992;Trasar-Cepada et al, 2007), which is probably due to the differences in the tested soil.…”

“…HQ inhibition of urease was least known of all three inhibitors studied here. However, it is suspected that for this inhibition responsibility was trace amounts of quinone, behaving with a double mode of inhibitory action on urease, namely through the arylation of the enzyme thiol group and reactive oxygen species (ROS) generation, notably H 2 O 2 , resulting in the oxidation of the thiol group ( Krajewska and Zaborska, 2007;Zaborska et al, 2007). NBPT had higher effects on urease inhibition than PPD in soil, which could be due to the formation of a compound (NBPTO, N-(nbutyl) phosphoric triamide) that is much more effective that NBPT for inhibition of urease activity (Andrews et al, 1986;Chai et al, 1988;McCarty and Bremner, 1989;Christianson et al, 1990;Benini et al, 1996).…”

“…30 days vs. 10 days). It appears that initially PPD inhibited urease activity, and during this time at least part of the PPD was converted to diamidophosphate (DAP); then as the activity of PPD declined, DAP began to inhibit soil urease (Hendrickson and O'Connor, 1987;Krajewska and Zaborska, 2007).…”

Synthesis, inhibitory activity and molecular docking studies of two Cu(II) complexes against Helicobacter pylori urease

“…The Cu(II) ion showed weaker inhibitory activity against urease than the complexes because the ligands probably strengthened inhibitory activity of the complexes. At the same time, the IC 50 of the Cu(II) ion was higher than that of the literature 24,25 . The results are agree with the data of the Cu(II) complex and AHA reported previously 26 , but are much stronger than the activity of the silver(I) carboxylate complex 11 .…”

Synthesis, antibacterial, antielastase, antiurease and antioxidant activities of new methoxy substitued bis-1,2,4-triazole derivatives

“…A variety of ureases (E.C.3.5.1.5) are found in bacteria, fungi, higher plants and in soil as soil enzymes. Medically, bacterial ureases are important virulence factors implicated in the pathogenesis of many clinical conditions such as pyelonephritis, hepatic coma, peptic ulcerationn and the formation of injection-induced urinary stones 9 …”