A5100763633- Photosynthetic Processes and Mechanisms
- Metalloenzymes and iron-sulfur proteins
- Hemoglobin structure and function
- Electron Spin Resonance Studies
- Metal-Catalyzed Oxygenation Mechanisms
- Glycosylation and Glycoproteins Research
- Enzyme Production and Characterization
- Neuroscience and Neuropharmacology Research
- DNA and Nucleic Acid Chemistry
- Carbohydrate Chemistry and Synthesis
- Enzyme Structure and Function
- Electrochemical sensors and biosensors
- Electrochemical Analysis and Applications
- Heme Oxygenase-1 and Carbon Monoxide
- Free Radicals and Antioxidants
- Biofuel production and bioconversion
- Photochemistry and Electron Transfer Studies
- Electron and X-Ray Spectroscopy Techniques
- Porphyrin Metabolism and Disorders
- Photoreceptor and optogenetics research
- Radiation Shielding Materials Analysis
- Adenosine and Purinergic Signaling
- X-ray Spectroscopy and Fluorescence Analysis
- Advanced biosensing and bioanalysis techniques
- Nitric Oxide and Endothelin Effects
Osaka University
2013-2025
University of Tsukuba
1984-2024
Saitama Prefecture
2023
Osaka Research Institute of Industrial Science and Technology
2009-2022
Sakai Municipal Hospital
2015
Kyowa Kirin (Japan)
2008-2012
Kyushu University
1994-2011
Kissei Pharmaceutical (Japan)
2005-2010
Kirin (Japan)
1990-2006
Toho University
1992-2005
The most important function of carotenoid pigments, especially beta-carotene in higher plants, is to protect organisms against photooxidative damage (G. Britton, T. W. Goodwin, ed., Plant Pigments--1988, 1988; N. I. Krinsky, O. Isler, H. Gutmann, and U. Solms, Carotenoids--1971, 1971). beta-Carotene also functions as a precursor vitamin A mammals A. J. Pitt, Osler, enzymes genes which mediate the biosynthesis cyclic carotenoids such are virtually unknown. We have elucidated for first time...
The dynamics of one-electron oxidation guanine (G) base mononucleotide and that in DNA have been investigated by pulse radiolysis. radical cation (G+*) deoxyguanosine (dG), produced with SO(4)-*, rapidly deprotonates to form the neutral G (G(-H)*) a rate constant 1.8 x 10(7) s(-1) at pH 7.0, as judged from transient spectroscopy. With experiments using different double-stranded oligonucleotides containing G, GG, GGG sequences, absorbance increases 625 nm, characteristic formation G(-H)*,...
The [2Fe-2S] transcription factor SoxR, a member of the MerR family, functions as bacterial sensor oxidative stress such superoxide and nitric oxide. SoxR is activated by reversible one-electron oxidation cluster then enhances production various antioxidant proteins through soxRS regulon. In active state, other family activate from unique promoters, which have long 19- or 20-bp spacer between -35 -10 operator elements, untwisting promoter DNA. Here, we show crystal structures its complex...
The kidneys play pivotal roles in acid-base homeostasis, and the acid-secreting (α-type) bicarbonate-secreting (β-type) intercalated cells collecting ducts are major sites for final modulation of urinary acid secretion. Since H+-ATPase anion exchanger activities these two types exhibit opposite polarities, it has been suggested that α- β-intercalated interchangeable via a cell polarity change. Immunohistological studies, however, have failed to confirm apical is band 3 protein localized...
Oxidative metabolism of omeprazole (OPZ) was studied in 14 human liver microsomes relation to the 4'-hydroxylation capacity S-mephenytoin. The formation 5-hydroxyomeprazole and sulfone (OPZ-SFN) from OPZ exhibited a biphasic kinetic behavior, indicating that at least two distinct enzymes are involved either metabolic pathways OPZ. By using two-enzyme approach, activities were described by high (Km1 Vmax1)- low-affinity components (Km2 Vmax2). respective mean (+/- S.D.) parameters for...
We have studied the time course of absorption bovine liver catalase after pulse radiolysis with oxygen saturation in presence and absence superoxide dismutase. In dismutase, produced Compound I another species. The formation is due to reaction ferric hydrogen peroxide, which generated by disproportionation anion (O-2). kinetic difference spectrum showed that other species was neither nor II. this found be inhibited, whereas little affected. This suggests formed O-2 probably oxy form enzyme...
We have isolated, cloned and characterized three cDNAs two genomic DNAs corresponding to the mRNAs genes for horseradish (Armoracia rusticana) peroxidase isoenzyme C (HPR C). The amino acid sequence of HRP C1, deduced from nucleotide one cDNA clone, pSK1, contained same primary as that purified enzyme established by Welinder [FEBS Lett. 72, 19-23 (1976)] with additional sequences at N terminal. All inserts in clones, pSK2 pSK3, coded size peptide (308 residues) if these are processed way,...
A plasmid has been constructed by cloning the complete crtI gene encoding phytoene desaturase from Erwinia uredovora behind lac Z promoter of pUC18 resulting in a reading frame for full polypeptide with additional 9 amino acids at N terminus. This mediated overexpression transformed Escherichia coli. The overexpressed enzyme was sequestrated into inclusion bodies requiring urea treatment solubilization. Purification to homogeneity subsequently performed on DEAE-cellulose column and...
Mucin-type O-glycans are the most typical found in mammalian cells and assume many different biological roles. Here, we report a genetic engineered yeast strain capable of producing mucin-type sugar chains. Genes encoding Bacillus subtilis UDP-Gal/GalNAc 4-epimerase, human transporter, ppGalNAc-T1, Drosophila melanogaster core1 beta1-3 GalT were introduced into Saccharomyces cerevisiae. The was able to produce MUC1a peptide containing O-glycan also mucin-like glycoprotein, podoplanin (hPod;...
The deprotonation of guanine cation radical (G+•) in oligonucleotides (ODNs) was measured spectroscopically by nanosecond pulse radiolysis. G+• ODN, produced oxidation with SO4−•, deprotonates to form the neutral G (G(-H)•). In experiments using 5-substituted cytosine-modified substitution cytosine C5 hydrogen a methyl group increased rate constant deprotonation, whereas replacement bromine decreased constant. Kinetic solvent isotope effects on kinetics deoxyguanosine (dG) and ODN duplexes...
YddV from Escherichia coli (Ec) is a novel globin-coupled heme-based oxygen sensor protein displaying diguanylate cyclase activity in response to availability. In this study, we quantified the turnover numbers of active [Fe(III), 0.066 min−1; Fe(II)−O2 and Fe(II)−CO, 0.022 min−1] Fe(III)−protoporphyrin IX complex; Fe(II), Fe(II)−protoporphyrin complex] inactive forms [Fe(II) Fe(II)−NO, <0.01 for first time. Our data indicate that reaction rate-determining step two consecutive reactions...
The differential cross sections of the Σ^{-}p→Λn reaction were measured accurately for Σ^{-} momentum (p_{Σ}) ranging from 470 to 650 MeV/c at J-PARC Hadron Experimental Facility. Precise angular information about was obtained first time by detecting approximately 100 events each step Δcosθ=0.1. show a slightly forward-peaking structure in regions. integrated -0.7≤cosθ≤1.0 as 22.5±0.68 [statistical error(stat.)] ±0.65 [systematic error(syst.)] mb and 15.8±0.83(stat)±0.52(syst)...
SoxR containing a [2Fe-2S] cluster required for its transcription activity functions as bacterial stress-response sensor that is activated through oxidation by redox-active compounds (RACs). from Escherichia coli (EcSoxR) nearly all RACs nonspecifically. In contrast, nonenteric SoxRs such Pseudomonas aeruginosa (PaSoxR), and Streptomyces coelicolor (ScSoxR) activate their target genes in response to RAC including endogenously produced metabolites. To investigate the determinants of SoxR's...
A polyphasic taxonomic study was performed on Sphingomonas sp. strain RW1T. The organism isolated from water of the River Elbe and has been known as a potent metabolizer dibenzo-p-dioxin its relatives. TLC mild alkaline hydrolysate extractable cellular lipids RW1T type strains 21 species gave spot sphingoglycolipid (SGL)-1 (glucuronosyl ceramide), which is characteristic sphingomonads. In addition, three (Sphingomonas yanoikuyae, terrae macrogoltabidus) showed second SGL (SGL-1')...
Two-component signal transduction systems regulate numerous important physiological functions in bacteria. In this study we have identified, cloned, overexpressed, and characterized a dimeric full-length heme-bound (heme:protein, 1:1 stoichiometry) globin-coupled histidine kinase (AfGcHK) from Anaeromyxobacter sp. strain Fw109-5 for the first time. The Fe(III), Fe(II)-O2, Fe(II)-CO complexes of protein displayed autophosphorylation activity, whereas Fe(II) complex had no significant...