A5039684786- Energetic Materials and Combustion
- Bioactive Compounds and Antitumor Agents
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Synthesis and biological activity
- Synthesis and Biological Evaluation
- Free Radicals and Antioxidants
- Thermal and Kinetic Analysis
- Chemical Reaction Mechanisms
- Phenothiazines and Benzothiazines Synthesis and Activities
- Chemical Reactions and Mechanisms
- Redox biology and oxidative stress
- Cancer therapeutics and mechanisms
- Organic Chemistry Cycloaddition Reactions
- Toxic Organic Pollutants Impact
- Synthesis and Characterization of Heterocyclic Compounds
- Combustion and Detonation Processes
- Genomics, phytochemicals, and oxidative stress
- Photosynthetic Processes and Mechanisms
- Malaria Research and Control
- Heme Oxygenase-1 and Carbon Monoxide
- Metal-Catalyzed Oxygenation Mechanisms
- Enzyme Catalysis and Immobilization
- Molecular Sensors and Ion Detection
- Crystallography and molecular interactions
Vilnius University
2016-2025
Institute of Biochemistry
1997-2009
Lithuanian Academy of Sciences
1999-2003
Albert Einstein College of Medicine
1994
With the aim to clarify mechanism(s) of action nitroaromatic compounds against malaria parasite Plasmodium falciparum, we examined single-electron reduction by P. falciparum ferredoxin:NADP+ oxidoreductase (PfFNR) a series nitrofurans and nitrobenzenes (n = 23), their ability inhibit glutathione reductase (PfGR). The reactivity nitroaromatics in PfFNR-catalyzed reactions increased with midpoint potential (E17). Nitroaromatic acted as non- or uncompetitive inhibitors towards PfGR respect...
Mammalian thioredoxin reductases (TrxR) are important selenium-dependent antioxidant enzymes. Quinones, a wide group of natural substances, human drugs, and environmental pollutants may act either as TrxR substrates or inhibitors. Here we systematically analyzed the interactions with different classes quinone compounds. We found that catalyzed mixed single- two-electron reduction quinones, involving both selenium-containing motif second redox center, presumably FAD. Compared other related...
Here we described novel interactions of the mammalian selenoprotein thioredoxin reductase (TrxR) with nitroaromatic environmental pollutants and drugs. We found that TrxR could catalyze nitroreductase reactions either one- or two-electron reduction, using its selenocysteine-containing active site another redox center, presumably FAD. Tetryl p-dinitrobenzene were most efficient substrates a k(cat) 1.8 2.8 s(-1), respectively, at pH 7.0 25 degrees C 50 muM NADPH. As nitroreductase, cycled...
Background The search for novel chemical entities targeting essential and parasite-specific pathways is considered a priority neglected diseases such as trypanosomiasis leishmaniasis. thiol-dependent redox metabolism of trypanosomatids relies on bis-glutathionylspermidine [trypanothione, T(SH)2], low molecular mass cosubstrate absent in the host. In pathogenic trypanosomatids, single enzyme, trypanothione synthetase (TryS), catalyzes biosynthesis, which indispensable parasite survival. Thus,...
In this paper, we present our investigations on the detonation performance and stability variations caused by replacing -CF₃ or -OCF₃ group with -SF₅. The widely adopted DFT B3LYP/cc-pVTZ approach was employed to evaluate HOMO-LUMO gap, cohesive energy, chemical hardness, electronegativity. Based these parameters, predict thermal changes resulting from inclusion of -SF₅ instead -OCF₃. Our results indicate that, in some cases, density fluorine-containing nitro compounds decreases due presence...
The aim of this study was to evaluate bioactive properties Basidiomycota fungi, mainly Suillus sp. Wide spectrum activities were revealed for S. variegatus, luteus, bovinus and granulatus; obtained results compared with other common fungi. Total Phenolic Content (TPC) varied from 245.32 ± 5.45 580.77 13.10 (mg (GAE) per 100 g dry weight) in methanolic extracts granulatus fruiting bodies, respectively. In ethyl acetate extracts, the highest TPC variegatus (310 9.68, mg (GAE)/100 g, matter),...
In this paper, we present our investigations into the detonation performance and stability variations caused by replacing -CF3 or -OCF3 group with -SF5. The widely applied DFT B3LYP/cc-pVTZ approach was employed to evaluate HOMO–LUMO gap, cohesive energy, chemical hardness, electronegativity. Based on these parameters, predict changes in thermal resulting from inclusion of -SF5 instead -OCF3. Our results indicate that, some cases, density fluorine-containing nitro compounds decreases due...
Ferredoxin:NADP+ oxidoreductase from Plasmodium falciparum (PfFNR) catalyzes the NADPH-dependent reduction of ferredoxin (PfFd), which provides redox equivalents for biosynthesis isoprenoids and fatty acids in apicoplast. Like other flavin-dependent electrontransferases, PfFNR is a potential source free radicals quinones cycling compounds. We report here kinetic study quinones, nitroaromatic compounds aromatic N-oxides by PfFNR. show that all these groups are reduced single-electron pathway,...
We aimed to elucidate the role of electronic and structural parameters nitroaromatic compounds in their two-electron reduction by NAD(P)H:quinone oxidoreductase (NQO1, DT-diaphorase, EC 1.6.99.2). The multiparameter regression analysis shows that reactivity (n=38) increases with an increase single-electron potential torsion angle between nitrogroup(s) aromatic ring. binding efficiency nitroaromatics active center NQO1 exerted a less evident reactivity. is characterized more positive...
Enterobacter cloacae PB2 NADPH:pentaerythritol tetranitrate reductase (PETNR) performs the biodegradation of explosive organic nitrate esters via their reductive denitration. In order to understand enzyme substrate specificity, we have examined reactions PETNR with nitrates (n = 15) and nitrogen analogues, N-nitramines 4). The these compounds were accompanied by release 1-2 mol nitrite per mole compound, but not redox cycling superoxide formation. reduction rate constants (k(cat)/K(m))...
Derivatives of tirapazamine and other heteroaromatic N-oxides (ArN→O) exhibit promising antibacterial, antiprotozoal, tumoricidal activities. Their action is typically attributed to bioreductive activation free radical generation. In this work, we aimed clarify the mechanism(s) aerobic mammalian cell cytotoxicity ArN→O performing parallel studies their reactions with NADPH:cytochrome P-450 reductase (P-450R), adrenodoxin reductase/adrenodoxin (ADR/ADX), NAD(P)H:quinone oxidoreductase (NQO1);...
Introduction: The identification of chemical compounds that interfere with SARS-CoV-2 replication continues to be a priority in several academic and pharmaceutical laboratories. Computational tools approaches have the power integrate, process analyze multiple data short time. However, these initiatives may yield unrealistic results if applied models are not inferred from reliable resulting predictions confirmed by experimental evidence. Methods: We undertook drug discovery campaign against...
Abstract Aromatic N ‐oxides (ArN−OX) are desirable biologically active compounds with a potential for application in pharmacy and agriculture industries. As biocatalysis is making great impact organic synthesis, there still lack of efficient convenient enzyme‐based techniques the production aromatic ‐oxides. In this study, recombinant soluble di‐iron monooxygenase (SDIMO) PmlABCDEF overexpressed Escherichia coli was showed to produce various N‐ oxides. Out 98 tested ‐heterocycles, seventy...