A5077098352- Photoreceptor and optogenetics research
- Neuroscience and Neuropharmacology Research
- bioluminescence and chemiluminescence research
- Photosynthetic Processes and Mechanisms
- Retinal Development and Disorders
- Drug Transport and Resistance Mechanisms
- Light effects on plants
- Molecular Communication and Nanonetworks
- Amino Acid Enzymes and Metabolism
- Circadian rhythm and melatonin
- Nicotinic Acetylcholine Receptors Study
- Advanced NMR Techniques and Applications
- Mass Spectrometry Techniques and Applications
- Chemical Reactions and Isotopes
- Lipid Membrane Structure and Behavior
- RNA and protein synthesis mechanisms
- thermodynamics and calorimetric analyses
- Photochromic and Fluorescence Chemistry
- Molecular spectroscopy and chirality
- Spectroscopy Techniques in Biomedical and Chemical Research
- Analytical Chemistry and Chromatography
- Molecular Sensors and Ion Detection
- Metal-Catalyzed Oxygenation Mechanisms
- Biopolymer Synthesis and Applications
- Cyclopropane Reaction Mechanisms
Toho University
2013-2023
Sojo University
2020-2023
Matsuyama University
2009-2018
Systems Biology Institute
2009-2016
Hokkaido University
2000-2010
RIKEN Center for Integrative Medical Sciences
2006-2008
Kobe Pharmaceutical University
2004-2006
Nagoya Institute of Technology
2002-2006
Weizmann Institute of Science
2005
University of California, Irvine
2005
The effects of bovine serum albumin and human on the unbound hepatic uptake clearance (<i>PS</i><sub>u,inf</sub>) organic anion–transporting polypeptide substrates 1-anilino-8-naphthalene sulfonate (ANS) pitavastatin (PTV) were determined using primary cultured rat hepatocytes isolated hepatocytes, respectively. <i>PS</i><sub>u,inf</sub> value was estimated by dividing initial rate these anions their concentrations. values for ANS PTV enhanced in presence albumin, thereby demonstrating...
Pharaonis phoborhodopsin, the photoreceptor of negative phototaxis archaebacterial Natronobacterium pharaonis , was functionally expressed in heterologous system Escherichia coli . Flash‐photolysis on a millisecond time scale indicated that photochemical properties p pR E. were same as those native N. We concluded integral membrane protein is correctly folded vivo eubacterial membrane.
There are two types of membrane-embedded ion transport machineries in nature. The pumps generate electrochemical potential by energy-coupled active transportation, while the channels produce action stimulus-dependent passive transportation. About 80% amino acid residues light-driven proton pump archaerhodopsin-3 (AR3) and light-gated cation channel channelrhodopsin (ChR) differ although they share close similarity architecture. Therefore, question arises: How can these proteins function...
Cell-free expression has become a highly promising tool for the efficient production of membrane proteins. In this study, we used dialysis-based Escherichia coli cell-free system protein actively integrated into liposomes. The was light-driven proton pump bacteriorhodopsin, consisting seven transmembrane alpha-helices. in dialysis mode supplemented with combination detergent and natural lipid, phosphatidylcholine from egg yolk, only reaction mixture. By examining variety detergents, found...
Abstract V 1 -ATPases are highly conserved ATP-driven rotary molecular motors found in various membrane systems. We recently reported the crystal structures for Enterococcus hirae A 3 B DF (V ) complex, corresponding to catalytic dwell state waiting ATP hydrolysis. Here we present two other states obtained by soaking nucleotide-free crystals ADP. In presence of 20 μM ADP, ADP molecules bind three binding sites and cooperatively induce conformational changes third site an ATP-binding mode,...
Archaeal rhodopsins possess a retinal molecule as their chromophores, and light energy signal conversions are triggered by all-trans to 13-cis isomerization of the chromophore. Relaxation through structural changes protein then leads functional processes, proton pump in bacteriorhodopsin transducer activation sensory rhodopsins. In present paper, low-temperature Fourier transform infrared spectroscopy is applied phoborhodopsin from Natronobacterium pharaonis (ppR), photoreceptor for negative...
Halorhodopsin is a light-driven chloride ion pump. Chloride bound in the Schiff base region of retinal chromophore, and unidirectional transport probably enforced by specific hydrogen-bonding interaction with protonated internal water molecules. In this article, we study alterations molecules halorhodopsin Natronobacterium pharaonis (pHR) assigning their N−D O−D stretching vibrations D2O, respectively. Highly accurate low-temperature Fourier transform infrared spectroscopy revealed that...
Diffusion is a spontaneous process and one of the physicochemical phenomena responsible for molecular transport, rate which governed mainly by diffusion coefficient; however, few coefficients are available because measurement rates not straightforward. The translational coefficient related Stokes–Einstein equation to approximate radius diffusing molecule. Therefore, stable conformations small molecules were first calculated modeling. A simple rs an effective re then proposed estimated using...
Gout is a common disease resulting from hyperuricemia which causes acute arthritis. Recently, genome-wide association studies revealed an between serum uric acid levels and variant of leucine-rich repeat-containing 16A (LRRC16A) gene. However, it remains to be clarified whether LRRC16A contributes the susceptibility gout. In this study, we investigated relationship rs742132 in A total 545 Japanese male gout cases 1,115 individuals as control group were genotyped. A/A genotype significantly...
Carbidopa is used with l-DOPA (l-3,4-dihydroxyphenylalanine) to treat Parkinson's disease (PD). PD patients exhibit lower incidence of most cancers including pancreatic cancer, but the notable exception melanoma. The decreased cancer not due l-DOPA; however, relevance this phenomenon has been investigated. Here, we tested hypothesis that Carbidopa, independent l-DOPA, might elicit an anticancer effect. inhibited cell proliferation both in vitro and vivo Based on structural similarity...
Pharaonis phoborhodopsin (ppR) (also pharaonis sensory rhodopsin II) is a receptor of the negative phototaxis Natronobacterium pharaonis. ppR forms complex with its halobacterial transducer (pHtrII), and this transmits light signal to system in cytoplasm. The expressed C-terminal-His tagged truncated pHtrII (t-Htr) Escherichia coli (His means 6x histidine tag) form even presence 0.1% n-dodecyl-beta-D-maltoside, M-decay became about twice slower than that alone. photocycling rates under...
Natronobacterium pharaonis phoborhodopsin (ppR; also called N. sensory rhodopsin II, NpsRII) is a photophobic sensor in pharaonis, and has shorter absorption maximum (λmax, 500 nm) than those of other archaeal retinal proteins 560–590 such as bacteriorhodopsin (bR). We constructed chimeric between bR ppR to investigate the long range interactions effecting color regulation among proteins. The λmax B-DEFG/P-ABC was 545 nm, similar that expressed Escherichia coli 550 nm). means chimera...
pharaonis phoborhodopsin (ppR, also called sensory rhodopsin II, psRII) is a receptor for negative phototaxis in Natronobacterium pharaonis. It forms 2:2 complex with its transducer protein, pHtrII, membranes, and the association weakened by 2 orders of magnitude M intermediate. Such change believed to correspond transfer light signal pHtrII. In this paper, we applied Fourier transform infrared (FTIR) spectroscopy active intermediate absence presence The obtained difference FTIR spectra were...
pharaonis phoborhodopsin (ppR, also called sensory rhodopsin II, psRII) is a receptor for negative phototaxis in Natronobacterium pharaonis. It forms 2:2 complex with its transducer protein, pHtrII, membranes and transmits light signals through the change protein−protein interaction. We previously found that ppRK minus ppR spectrum D2O possesses vibrational bands of at 3479 (−)/3369 (+) cm-1 only presence pHtrII [Furutani, Y., Sudo, Kamo, N., Kandori, H. (2003) Biochemistry 42, 4837−4842]. A...
In the Schiff base region of bacteriorhodopsin (BR), a light-driven proton-pump protein, three internal water molecules are involved in pentagonal cluster structure. These constitute hydrogen-bonding network consisting two positively charged groups, and Arg82, negatively Asp85 Asp212. Previous infrared spectroscopy BR revealed stretching vibrations such under strong conditions using spectral differences D2O D218O [Kandori Shichida (2000) J. Am. Chem. Soc. 122, 11745−11746]. The present study...
Acetabularia rhodopsins are the first microbial discovered in a marine plant organism, acetabulum. Previously, we expressed rhodopsin II (ARII) by cell-free system from one of two opsin genes A. acetabulum cDNA and showed that ARII is light-driven proton pump [Wada, T., et al. (2011) J. Mol. Biol.411, 986–998]. In this study, photochemistry was examined using flash-photolysis technique, data were analyzed sequential irreversible model. Five photochemically defined intermediates (Pi)...
Although many crystal structures of microbial rhodopsins have been solved, those with sufficient resolution to identify the functional water molecules are very limited. In this study, Acetabularia rhodopsin I (ARI) protein derived from marine alga A. acetabulum was synthesized on a large scale by Escherichia coli cell-free membrane-protein production method, and ARI were determined at second highest (1.52-1.80 Å) for rhodopsin, following bacteriorhodopsin (BR). Examinations photochemical...
Proteorhodopsin, a retinal protein of marine proteobacteria similar to bacteriorhodopsin the archaea, is light-driven proton pump. Absorption light quantum initiates reaction cycle (turnover time ca. 50 ms), which includes photoisomerization from all-trans 13-cis form and transient deprotonation Schiff base, followed by recovery initial state. We report here that in addition this fast cyclic conversion, illumination at high pH results accumulation long-lived photoproduct absorbing 362 nm....