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The urease enzyme has been an important target for the discovery of effective pharmacological and agricultural products. Thirteen regio-selectively alkylated benzimidazole-2-thione derivatives have been designed to carry the essential features of urease inhibitors. The urease enzyme was isolated from Helicobacter pylori as a recombinant urease utilizing the His-tag method. The isolated enzyme was purified and characterized using chromatographic and FPLC techniques showing a maximal activity of 200 mg/mL. Additionally, the commercial Jack bean urease was purchased and included in this study for comparative and mechanistic investigations. The designed compounds were synthesized and screened for their inhibitory activity against the two ureases. Compound 2 inhibited H. pylori and Jack bean ureases with IC50 values of 0.11; and 0.26 mM; respectively. While compound 5 showed IC50 values of 0.01; and 0.29 mM; respectively. Compounds 2 and 5 were docked against Helicobacter pylori urease (PDB ID: 1E9Y; resolution: 3.00 Å) and exhibited correct binding modes with free energy (ΔG) values of −9.74 and −13.82 kcal mol−1; respectively. Further; the in silico ADMET and toxicity properties of 2 and 5 indicated their general safeties and likeness to be used as drugs. Finally, the compounds’ safety was authenticated by an in vitro cytotoxicity assay against fibroblast cells.

Clinically significant problems such as kidney stones and stomach ulcers are linked to the activation of the urease enzyme. At low pH, this enzyme gives an ideal environment to Helicobacter pylori in the stomach which is the cause of gastric ulcers and peptic ulcers. In recent work, we have developed a library of 4-fluorocinnamaldehyde base thiosemicarbazones and assessed them for their potential against urease enzyme. The synthesized compounds displayed significant to moderate inhibition potential with IC 50 values ranging from 2.7 ± 0.5 µM to 29.0 ± 0.5 µM. compound 3c displayed the highest inhibition potential followed by 3a and 3b . Two compounds of the series 3f and 3 g remained inactive against urease. The kinetic study of compound 3c exhibited a competitive type of inhibition with a K i value of 3.26 ± 0.0048 µM. SAR analysis was also thoroughly done. Molecular docking was used to analyze the interaction pattern of each derivative, and the outcomes demonstrated that the compounds had excellent binding interactions with the active site.

The development of new bioactive compounds is important for progress in therapeutic research. In the present study, we describe the multistep synthetic approach to develop a library of novel benzimidazole analogs incorporating piperazine rings in order to increase their biological activity. In order to synthesize the desired benzimidazole analogs, the synthesis started with the easily accessible precursors between aniline and chloroacetyl chloride. It proceeded via a series of reactions, such as condensation, cyclization, and N -alkylation. TLC optimized each step, and spectroscopic methods such as CHN, IR, EIMS, 1 H-NMR, and 13 C-NMR were used to characterize the final products. The urease inhibitory activity of the synthesized compounds was evaluated. It was discovered that almost all compounds were quite effective, even more potent (IC 50  = 0.15–12.17 µ M) than the standard thiourea (IC 50  = 23.11 ± 0.21 µ M). The structure-activity relationship (SAR) is also established, which displayed that compound 9 L (IC 50  = 0.15 ± 0.09 µ M) with -NO 2 substitutions at meta position play a major role in urease inhibition and figure out as the most potent analog of the library. These results were further verified by molecular docking analysis, which indicated favorable binding energies and interactions of the compounds with the urease active site. This study not only depicts the importance of multistep synthesis but also the structure-based modification approach to produce new pharmacophores for therapeutic applications.

Staphylococcus aureus causes acute and chronic infections resulting in significant morbidity. Urease, an enzyme that generates NH3 and CO2 from urea, is key to pH homeostasis in bacterial pathogens under acidic stress and nitrogen limitation. However, the function of urease in S. aureus niche colonization and nitrogen metabolism has not been extensively studied. We discovered that urease is essential for pH homeostasis and viability in urea-rich environments under weak acid stress. The regulation of urease transcription by CcpA, Agr, and CodY was identified in this study, implying a complex network that controls urease expression in response to changes in metabolic flux. In addition, it was determined that the endogenous urea derived from arginine is not a significant contributor to the intracellular nitrogen pool in non-acidic conditions. Furthermore, we found that during a murine chronic renal infection, urease facilitates S. aureus persistence by promoting bacterial fitness in the low-pH, urea-rich kidney. Overall, our study establishes that urease in S. aureus is not only a primary component of the acid response network but also an important factor required for persistent murine renal infections.

Nitrification, the sequential aerobic oxidation of ammonia via nitrite to nitrate, is a key process of the biogeochemical nitrogen cycle and catalyzed by two aerobic microbial guilds (nitrifiers): ammonia oxidizers and nitrite-oxidizing bacteria (NOB). NOB are generally considered as metabolically restricted and dependent on ammonia oxidizers. Here, we report that, surprisingly, key NOB of many ecosystems ( Nitrospira ) convert urea, an important ammonia source in nature, to ammonia and CO 2 . Thus, Nitrospira supply urease-negative ammonia oxidizers with ammonia and receive nitrite produced by ammonia oxidation in return, leading to a reciprocal feeding interaction of nitrifiers. Moreover, Nitrospira couple formate oxidation with nitrate reduction to remain active in anoxia. Accordingly, Nitrospira are unexpectedly flexible and contribute to nitrogen cycling beyond nitrite oxidation. Nitrospira are a diverse group of nitrite-oxidizing bacteria and among the environmentally most widespread nitrifiers. However, they remain scarcely studied and mostly uncultured. Based on genomic and experimental data from Nitrospira moscoviensis representing the ubiquitous Nitrospira lineage II, we identified ecophysiological traits that contribute to the ecological success of Nitrospira . Unexpectedly, N. moscoviensis possesses genes coding for a urease and cleaves urea to ammonia and CO 2 . Ureolysis was not observed yet in nitrite oxidizers and enables N. moscoviensis to supply ammonia oxidizers lacking urease with ammonia from urea, which is fully nitrified by this consortium through reciprocal feeding. The presence of highly similar urease genes in Nitrospira lenta from activated sludge, in metagenomes from soils and freshwater habitats, and of other ureases in marine nitrite oxidizers, suggests a wide distribution of this extended interaction between ammonia and nitrite oxidizers, which enables nitrite-oxidizing bacteria to indirectly use urea as a source of energy. A soluble formate dehydrogenase lends additional ecophysiological flexibility and allows N. moscoviensis to use formate, with or without concomitant nitrite oxidation, using oxygen, nitrate, or both compounds as terminal electron acceptors. Compared with Nitrospira defluvii from lineage I, N. moscoviensis shares the Nitrospira core metabolism but shows substantial genomic dissimilarity including genes for adaptations to elevated oxygen concentrations. Reciprocal feeding and metabolic versatility, including the participation in different nitrogen cycling processes, likely are key factors for the niche partitioning, the ubiquity, and the high diversity of Nitrospira in natural and engineered ecosystems.

Helicobacter pylori bacteria are involved in gastroduodenal disorders, including gastric adenocarcinoma. Since the current therapies encounter with some significant shortcomings, much attention has been paid to the development of new alternative diagnostic and treatment modalities such as immunomedicines to target H. pylori . Having used phage display technology, we isolated fully humane small antibody (Ab) fragment (V L ) against the Flap region of urease enzyme of H. pylori to suppress its enzymatic activity. Solution biopanning (SPB) and screening process against a customized biotinylated peptide corresponding to the enzyme Flap region resulted in the selection of V L single domain Abs confirmed by the enzyme-linked immunosorbent assay (ELISA), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and Western blotting. The selected Ab fragments showed a high affinity with a K D value of 97.8 × 10 −9 and specificity to the enzyme with high inhibitory impact. For the first time, a V L single domain Ab was isolated by SPB process against a critical segment of H. pylori urease using a diverse semi-synthetic library. Based on our findings, the selected V L Ab fragments can be used for the diagnosis, imaging, targeting, and/or immunotherapy of H. pylori . Further, Flap region shows great potential for vaccine therapy.

The present study demonstrated the design and synthesis of sulfonamide-1,2,3-triazole-acetamide derivatives 11a-o and screening against urease in vitro and in silico. These compounds were designed based on reported potent urease inhibitors and optimized structurally based on substituents on acetamide moiety. In vitro studies showed that all the new compounds 11a-o (IC 50 values = 0.12–4.53 µM) were more potent than stand inhibitor thiourea (IC 50 value = 23.76 µM). In this regard, the most potent compounds were N-phenylacetamide derivatives 11b , 11f , and 11 h with 2-methyl, 4-methoxy, and 2-fluoro substituents, respectively. In this regard, the most potent compound 11b was 198-folds more potent than thiourea against urease. In silico studies demonstrated that this compound with the binding energy less than thiourea attached to the urease’s active site. Druglikeness, pharmacokinetics, and toxicity of compound 11b and thiourea were predicted by two credible online servers. These in silico studies showed that, in terms of druglikeness and pharmacokinetics, compound 11b was almost similar to thiourea while in term of toxicity, compound 11b was better than thiourea.

A urease inhibitor with good in vivo profile is considered as an alternative agent for treating infections caused by urease-producing bacteria such as Helicobacter pylori. Here, we report a series of N-monosubstituted thioureas, which act as effective urease inhibitors with very low cytotoxicity. One compound (b19) was evaluated in detail and shows promising features for further development as an agent to treat H. pylori caused diseases. Excellent values for the inhibition of b19 against both extracted urease and urease in intact cell were observed, which shows IC 50 values of 0.16 ± 0.05 and 3.86 ± 0.10 µM, being 170- and 44-fold more potent than the clinically used drug AHA, respectively. Docking simulations suggested that the monosubstituted thiourea moiety penetrates urea binding site. In addition, b19 is a rapid and reversible urease inhibitor, and displays nM affinity to urease with very slow dissociation (k off =1.60 × 10 −3  s −1 ) from the catalytic domain.

Biological macromolecules can condense into liquid domains. In cells, these condensates form membraneless organelles that can organize chemical reactions. However, little is known about the physical consequences of chemical activity in and around condensates. Working with model bovine serum albumin (BSA) condensates, we show that droplets swim along chemical gradients. Active BSA droplets loaded with urease swim toward each other. Passive BSA droplets show diverse responses to externally applied gradients of the enzyme’s substrate and products. In all these cases, droplets swim toward solvent conditions that favor their dissolution. We call this behavior “dialytaxis”, and expect it to be generic, as conditions which favor dissolution typically reduce interfacial tension, whose gradients are well-known to drive droplet motion through the Marangoni effect. These results could potentially suggest alternative physical mechanisms for active transport in living cells, and may enable the design of fluid micro-robots. Here the authors identify a generic coupling in phase-separated liquids between motility and phase equilibria perturbations: phase-separated droplets swim to their dissolution. This suggests alternative transport mechanism for biomolecular condensates.