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Research has been conducted on nonequivalent molecules in the photosystem II reaction center. The results of spectroscopic characterization of nonequivalent beta-carotine molecules in this reaction center are reported.

Research has been conducted on active Rac and RacQ61L. The study of the oxidase activity has been carried out via the use of constitutively active Rac and RacQ61L, and the results demonstrate that RacQ61L mutant stabilizes oxidase activity.

Research has been conducted on Fapy.dA which is produced in DNA as an oxidative stress result. The study of interactions between DNA containing Fapy.dA with repair enzyme MutY and bifunctional enzyme Fpg is described.

Research has been conducted on catalytic hydrogen evolution and oxidation by Allochromatium vinosum [NiFe]-hydrogenase. The mechanism of these evolution and oxidation has been investigated via the use of protein film voltammetry, and the catalytic cycle energetics have been determined and discussed.

Research has been conducted on photosynthetic water oxidation which is carried out via the light-driven S-state cycle in photosystem II water-oxidizing complex. The molecular mechanism monitoring substrate water reaction in each S-state transition has been investigated, and the results are reported.

Research has been conducted on TF (sub)1 component of Bacillus PS3 F (sub)0 F (sub)1 -ATP synthases. The fluorescence titrations of TF (sub)1 subcomplexes with nucleotides demontrate that betaG (super)156 C substitution lowers catalytic site affinity for ATP and ADP, and the results suggest that betaG (super)156 C substitution strain causes defective oxidative phosphorylation.

Research has been conducted on D-alanine oxidation. The study of this oxidation catalyzed by flavoenzyme D-amino acid oxidase has been carried out via molecular dynamics simulations, and the results demonstrate that the first-principle molecular dynamics approach can be used for the study of complex enzymatic process mechanism.

Research has been conducted on the yeast cytochrome c peroxidase. The study of electron-transfer chemistry of this peroxidase and the structural control of the heme proteins' oxidative intermediates have been carried out via the use of spin-trapping reagent and mass spectrometry, and the details are reported.

Research has been conducted on the DNA-peptide cross-linking. The study of this cross-linking carried out via peptide attachment to the ruthenium intercalator demonstrate that these peptides provide functional groups which react with the oxidized DNA producing cross-links.

Research has been conducted on Pseudomonas putida (S)-Mandelate dehydrogenase. The catalytic role of arginine residues Arg 165 and Arg 277 present in these enzymes and the importance of Arg165/Arg277 pair have been investigated and the results are reported.

Research has been conducted on the malic enzyme reaction. The substrates for this reactions have been identified and characterized with respect to the reaction catalyzed and reaction's kinetics and the results have been compared to those observed with L-malate.

Research has been conducted on the tartrate dehydrogenase mechanism. The analysis of this mechanism has been carried out via the multiple isotope effect studies in investigating the hypothesis that the change in mechanism is a phenomenon of the divalent metal ion-dependent oxidative decarboxylase.

Research has been conducted on Escherichia coli thioredoxin chimera. The solution structure of both human and E. coli thioredoxin's oxidized form has been investigated via the use of NMR spectroscopy and the thermodynamic stability of this hybrid protein has been examined and is described.

Research has been conducted on the guanidines related to L-arginine. The oxidation of these compounds carried out via the recombinant NO-synthase II has produced a non-alpha-amino acid guanidine NO-synthase II substrate which acts as NO precursor.

Research has been conducted on the Mycobacterium tuberculosis oxidoreductase FprA. The crystal structure of FprA has been investigated in different redox states obtained via oxidized enzyme cocrystallization with NADP (super)+ and via soaking the crystals in NADPH-containing solution and the results are reported.

Research has been conducted on Candida tenius xylose reductase. The structures of the C. tenuis xylose reductase's apo- and holoenzyme have been investigated and the results suggest that modeling of xylose into the holoenzyme's active site indicates a substrate binding mode.

Research has been conducted on alpha-lactalbumin oxidative folding pathway. The characterization of this pathway has been carried out via kinetic and structural analysis of the acid-trapped folding intermediates and the results indicate that alpha-lactalbumin folding pathway's mechanism is congruent with the disulfide folding pathway diversity.

Research has been conducted on the chemically modified human and bovine hemoglobins. The systematic evaluation of these hemoglobins has been carried out and the toxicity of the hemoglobin-based oxygen carriers has been investigated in establishing the importance of the secondary oxidative reactions.

Research has been conducted on the protein conformation states. The use of the high-angle X-ray scattering in investigating these states in solution and the study of the oxidation state- and the temperature-dependent changes in cytochrome c solution scattering are described

Research has been conducted on the alpha1-antitrypsin, a flexible protein from the protease inhibitors' serpin family. The methionine and cysteine oxidation in this protein and the mechanism by which alpha1-antitrypsin's reactive methionines are oxidized at the neutral pH have been investigated and are discussed.

Research has been conducted on the Acidaminococcus fermentans 2-hydroxyglutaryl-CoA dehydratase. The isolation of flavodoxin from A. fermentans cell-free extracts has been carried out and the results demonstrate the postulated one-electron transfer from flavodoxin to the homodimeric activator.

Research has been conducted on the unnatural carbon-6 isomers. The bioactivity of these isomers has been investigated and the results suggest that cytochrome c oxidation of 10-formyltetrahydrofolate to 10-formyldihydrofolate in mitochondrial intermembrane space may explain the unnatural carbon-6 isomer bioactivity.

Research has been conducted on the cytochrome redox potential within a library of variants with the same structural four-helix bundle. The use of the cytochrome b (sub)562 in investigating the evolution of this redox potential in vitro is described.

Research has been conducted on the veratryl alcohol oxidation. The investigation of the site of this oxidation and the role of the veratryl alcohol in the lignin peroxidase has been carried out using the site-directed veratryl alcohol mutants produced via the homologous expression system.

Research has been conducted on cytochrome P450. The experiments have demonstrated that this cytochrome converts pinacidil's cyano group to the corresponding amide in human liver microsomes.

Research has been conducted on the human heat shock transcription factor 1. Results indicate that the redox-dependent thiol-disulfide exchange can regulate the conformation and activity of this transcription factor.

Research has been conducted on the proteins which play important role in Clostridium pasteurianum defense against oxidative damage compensating for the lack of catalase activity in this bacteria. Results indicate that these proteins comprise an alkyl hydroperoxide reductase system that catalyzes the NADH-dependent reduction of H (sub)2 O (sub)2 and organic hydroperoxides.

Research has been conducted on the Mn atoms which function as catalysts in the water-oxidizing complex in the PS II oxidizing site. The effect of the PS II proteins' amine groups on the photoligation of the Mn (super)2+ to the apo water-oxidizing complex has been investigated via photoactivation and chemical modification techniques and the results are discussed.

Research has been conducted on the red Cu protein nitrocyanine isolated from the nitrifying bacterium Nitrosomonas europaea. Results indicate that this protein is a homo-oligomer of the Cu-containing monomers.

Research has been conducted on the DNA hydrolysis. The artificial nucleases for this hydrolysis have been developed via tethering the metal-coordinating peptides to the DNA-intercalating rhodium complex in delivering metal ions to the sugar-phosphate backbone and the details are presented.

Research has been conducted on the beta-actin. The preparation of the oxidized beta-actin from the normal red blood cell beta-actin has been carried out via the chemical reaction in investigating the biological and chemical characterization of the oxidized beta-actin and the details are reported.

Research has been conducted on selenium biochemistry. The topics of interest include the studies of cholesterol oxidation, mammalian selenoprotein and anaerobic metabolic systems.

Research has been conducted on the chloroplast fructose 1,6-bisphosphatase (FBPase). The structural and functional properties of the conserved cysteines of the FBPase chloroplast loop have been investigated via the replacement of these cysteines by the site-directed mutagenesis and the analysis of their thiol content, Mg (super) 2+ dependence and redox potentials.

Research has been conducted on the photosystem I which conducts light-driven electron transfer from plastocyanin to ferredoxin via the reactions initiated by the photooxidized chlorophyll donor P (sub)700. Results indicate that the P (sub)700 photooxidation in the cyanobacterial photosystem I perturbs cysteine residue.

Research has been conducted on the anticancer anthracyclines doxorubicin and daunorubicin. The oxidation of these agents by the lactoperoxidase/H (sub)2 O (sub)2 and horseradish peroxidase/H (sub)2 O (sub)2 systems has been investigated via the spectrophotometric and EPR techniques in the presence and absence of NO (sub)2 (super)- and the results indicate that lactoperoxidase/H (sub)2 O (sub)2/NO (sub)2 (super)- causes the loss of the anthracyclines' absorption bands.

Research has been conducted on the snake neurotoxins, all-beta proteins displaying complex disulfide bond association. The oxidative folding of the neurotoxin variant (alpha)62 has been investigated in defining the chemical nature of the three-disulfide intermediates accumulated during the process to describe the folding pathway and the results are described.

Research has been conducted on the DNA photolyase, a flavoprotein reparing cyclobutylpyrimidine dimers. The steady-state and transient absorption spectra and excited-state decay kinetics of oxidized Escherichia coli DNA photolyase have been investigated and the results indicate that the steady-state absorption spectrum for the enzyme-polynucleotide substrate complex has demonstrated a blue shift.

Research has been conducted on the deuterium kinetic isotope effects. These effects determined for the cytochrome b (sub)6 f complex imply that the reductive electron transfer in cytochrome f is proton-coupled in the acidic pH range.

Research has been conducted on the nativelike intermediate des-[40-95] protein. The conformational folding of this protein of the oxidative folding pathway of bovine pancreatic ribonuclease A has been investigated at different pH and temperatures and the oxidative folding mechanism is discussed.

Research has been conducted on the tryptophans and tyrosines. The role of these amino acids in the yeast cytochrome c peroxidase has been examined via the site-directed mutagenesis and the results are presented.

Research has been conducted on the monoamine oxidase A. The role of the tyrosyl residues which are located near the covalent 8(alpha)-S-cysteinyl FAD in this oxidase has been investigated and the results are reported.

Research has been conducted on the Cyanobacterium anabaena oxidized flavodoxin. The use of this flavodoxin in investigating the internal dynamics of the flavin-bearing protein is described.

Research has been conducted on the four-residue reverse turn in the Clostridium beijerinckii flavodoxin that provides interactions with the isoalloxazine ring of the flavin mononucletide cofactor. The role of the loop and the functional inter-relationships and the synergistic interaction that might occur within the loop have been investigated and the results are discussed.

Research has been conducted on the methylamine dehydrogenase which is a tryptophan tryptophylquinone-dependent enzyme catalyzing the oxidative primary amine deamination. The putative monovalent cation binding sites in this methylamine dehydrogenase have been identified via the X-ray crystallography and the results are reported.

Research has been conducted on the endonuclease VIII of Escherichia coli involved in the base-excision repair of DNA oxidative damage. The substrate specificity and excision kinetics of this DNA glycosylase for the DNA bases damaged by the free radicals have been investigated and the results are reported.

Research has been conducted on the cytochrome b (sub)561, a membrane-bound protein. The reaction mechanism between this cytochrome and ascorbic acid and semidehydroascorbate has been investigated and the results are discussed.

Research has been conducted on the respiratory flavoenzyme, a membrane-extrinsic catalytic domain of Escherichia coli fumarate reductase. The energetics of electron transfer and substrate binding at this domain has been investigated via the protein film voltammetry and the results are reported.

Research has been conducted on the polycyclic aromatic hydrocarbons. These hydrocarbons have been metabolized to trans-dihydrodiols proximate carcinogens by human epoxide hydrolase and CYP1A1 and the results are discussed.

Research has been conducted on the ferritins, the iron storage and detoxification proteins. The use of sensitive fluorescence assay and based on O (sub)2 evolution assay in demonstrating that hydrogen peroxide is produced in horse spleen ferritin ia discussed.

Research has been conducted on the CYP3A4 amino acid residues. The substitution of these residues with the largest nonpolar amino acids has been carried out and the function has been assessed with four substrates yielding sigmoidal steady-kinetics with wild-type CYP3A4.