2021/04/08 更新

写真a

イマナカ ヒロユキ
今中 洋行
IMANAKA Hiroyuki
所属
自然科学学域 助教
職名
助教
外部リンク

学位

  • 博士(工学) ( 京都大学 )

研究キーワード

  • genetic engineering

  • immobilization

  • peptide

  • protein

  • hyperthemophile

  • 遺伝子工学

  • intermolecular interaction

  • 超好熱菌

  • 分子間相互作用

  • 固定化

  • ペプチド

  • タンパク質

  • protein engineering

  • タンパク質工学

研究分野

  • ライフサイエンス / 応用生物化学

  • ナノテク・材料 / 複合材料、界面

  • ライフサイエンス / 分子生物学

  • ライフサイエンス / 食品科学

  • ナノテク・材料 / 生体化学

  • ものづくり技術(機械・電気電子・化学工学) / バイオ機能応用、バイオプロセス工学

  • ナノテク・材料 / ナノバイオサイエンス

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学歴

  • 京都大学   大学院工学研究科   合成・生物化学専攻

    - 2003年3月

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  • 京都大学   大学院工学研究科   化学工学専攻

    - 1999年3月

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  • 京都大学   工学部   工業化学科

    - 1997年3月

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所属学協会

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委員歴

  • 日本生物工学会 若手会   会長  

    2017年9月 - 現在   

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    団体区分:学協会

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  • 日本農芸化学会   Frontiersシンポジウム実行委員長  

    2014年4月 - 2015年3月   

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    団体区分:学協会

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  • 日本農芸化学会中四国支部   参与  

    2013年4月 - 現在   

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    団体区分:学協会

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  • Young Asian Biological Engineers' Community (YABEC)   日本事務局メンバー  

    2011年6月 - 現在   

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    団体区分:学協会

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  • 岡山地区化学工学懇話会   幹事  

    2011年4月 - 現在   

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    団体区分:学協会

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  • 日本生物工学会西日本支部   幹事(会計)  

    2011年4月 - 2013年4月   

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    団体区分:学協会

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  • 日本生物工学会   若手研究者の集いセミナー実行委員長  

    2009年8月 - 2010年7月   

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    団体区分:学協会

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論文

  • Adsorption characteristics of various proteins on a metal surface in the presence of an external electric potential 査読

    Ei Ei Htwe, Yuhi Nakama, Yuko Yamamoto, Hiroshi Tanaka, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

    Colloids and Surfaces B: Biointerfaces166   262 - 268   2018年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Elsevier B.V.  

    The effect of the properties of a protein on its adsorption to a metal surface in the presence of external electric potential was investigated. Protein adsorption processes at different surface potentials were measured for fifteen types of proteins using an in-situ ellipsometry. The tested proteins were classified into three groups, based on the amount of protein that was adsorbed as a function of the surface potential: In First group of proteins, an increasing trend for the amount adsorbed with a more positive surface potential was found
    The amount adsorbed of α-chymotrypsinogen A and ribonuclease A (Second group) were roughly constant and independent of the applied surface electric potentials
    In Third group, the amount adsorbed decreased with increasing surface potential. This protein classification was correlated with the isoelectric points of the proteins (First group: ≤9.3
    Second group: 9.3–10
    Third group: &gt
    10). Increasing the pH positively and negatively shifted the surface potentials, allowing ß-lactoglobulin (First group) and lysozyme (Third) to become adsorbed, respectively. The surface potential range for protein adsorption was also markedly shifted depending on the metal substrate type. These findings were interpreted based on the electrostatic interactions among the protein, surface hydroxyl groups, and the applied external electric field.

    DOI: 10.1016/j.colsurfb.2018.03.035

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  • Controlling the drying process in vacuum foam drying under low vacuum conditions by inducing foaming by needle stimulation of the solution 査読

    Fumihiro Hidaka, Tomo Satoh, Akiho Fujioka, Koji Takeda, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

    Drying Technology36   2018年

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  • Influence of an external electric field on removal of protein fouling on a stainless steel surface by proteolytic enzymes 査読

    Ei Ei Htwe, Yuhi Nakama, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

    COLLOIDS AND SURFACES B-BIOINTERFACES159   118 - 124   2017年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    Enzymatic cleaning is a potentially useful method for removing proteinaceous fouling from solid surfaces under mild conditions. Herein, the influence of an external electric field on the enzymatic cleaning of a metal surface fouled with a protein was investigated. The model fouling protein (BSA; lysozyme) was prepared on a stainless steel (St) surface, and the resulting surface subjected to enzymatic cleaning with an electric potential being applied to the St plate. Trypsin, alpha-chymotrypsin, and thermolysin were used as model proteases. The amounts of protein remaining on the plate before and during the cleaning process were measured by means of a reflection absorption technique using Fourier transform infrared spectroscopy. In the case for BSA fouling, the cleaning efficiency of the protease tended to increase at more negative applied potentials. Whereas, there was an optimum applied potential for removing the lysozyme fouling. Atomic force microscopy analyses indicated that applying an adequate range of electric potential enhanced the enzymatic removal of protein fouling inside scratches on the St plate surface. These findings suggest the existence of two modes of electrostatic interactions for the external electric field, one with protease molecules and the other with digested fragments of the fouling protein. (C) 2017 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.colsurfb.2017.07.074

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  • Characteristics of proteinaceous additives in stabilizing enzymes during freeze-thawing and -drying 査読

    Takanori Shimizu, Tamayo Korehisa, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY81 ( 4 ) 687 - 697   2017年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

    Protein-stabilizing characteristics of sixteen proteins during freeze-thawing and freeze-drying were investigated. Five enzymes, each with different instabilities against freezing and dehydration, were employed as the protein to be stabilized. Proteinaceous additives generally resulted in greater enzyme stabilization during freeze-thawing than sugars while the degree of stabilization for basic lysozyme and protamine were inferior to that of neutral and acidic proteins. Freeze-drying-induced inactivation of enzyme was also reduced by the presence of a proteinaceous additive, the extent of which was lower than that for a sugar. In both freeze thawing and freeze drying, the enzymes stabilization by the proteinaceous additive increased with increasing additive concentration. The enhancement of enzyme inactivation caused by pH change was also reduced in the presence of proteinaceous additives. The combined use of a sugar such as sucrose and dextran tended to increase the stabilizing effect of the proteinaceous additive.

    DOI: 10.1080/09168451.2016.1274637

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  • Surfactant-Free Solid Dispersions of Hydrophobic Drugs in an Amorphous Sugar Matrix Dried from an Organic Solvent 査読

    Koji Takeda, Yuto Gotoda, Daichi Hirota, Fumihiro Hidaka, Tomo Sato, Tsutashi Matsuura, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

    MOLECULAR PHARMACEUTICS14 ( 3 ) 791 - 798   2017年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    The technique for homogeneously dispersing hydrophobic drugs in a water-soluble solid matrix (solid dispersion) is a subject that has been extensively investigated in the pharmaceutical industry. Herein, a novel technique for dispersing a solid, without the need to use a surfactant, is reported. A freeze-dried amorphous sugar sample was dissolved in an organic solvent, which contained a soluble model hydrophobic component. The suspension of the sugar and the model hydrophobic component was vacuum foam dried to give a solid powder. Four types of sugars and methanol were used as representative sugars and the organic medium. Four model drugs (indomethacin, ibuprofen, gliclazide, and nifedipine) were employed. Differential scanning calorimetry analyses indicated that the sugar and model drug (100:1) did not undergo segregation during the drying process. The dissolution of the hydrophobic drugs in water from the solid dispersion was then evaluated, and the results indicated that the C-max and AUC(0-60) (min) of the hydrophobic drug in water were increased when the surfactant-free solid dispersion was used. Palatinose and/or alpha-maltose were superior to the other tested carbohydrates in increasing C-max and AUC(0-60 min), for all tested model drugs, and the model drug with a lower water solubility tended to exhibit a greater extent of over-dissolution.

    DOI: 10.1021/acs.molpharmaceut.6b01048

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  • Surfactant-free solid dispersion of fat-soluble flavour in an amorphous sugar matrix 査読

    Tomo Satoh, Fumihiro Hidaka, Kento Miyake, Natsuki Yoshiyama, Koji Takeda, Tsutashi Matsuura, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

    FOOD CHEMISTRY197   1136 - 1142   2016年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCI LTD  

    A solid dispersion technique to homogeneously disperse hydrophobic ingredients in a water-soluble solid without using surfactant was examined as follows: first, freeze-dried amorphous sugar was dissolved in an organic medium that contained a soluble model hydrophobic component. Second, the mixed solution of sugar and the model hydrophobic component was vacuum dried into a solid (solid dispersion). Methanol and six fat-soluble flavours, including cinnamaldehyde, were used as organic media and model hydrophobic components. The retention of flavours in the solid dispersion during drying and storage under vacuum was evaluated. The amorphised disaccharides dissolved in methanol up to 100 mg/mL, even temporarily (20 s to 10 days) and could be solidified without any evidence of crystallisation and segregation from flavour. The solid dispersion, prepared using a-maltose usually showed 65-95% flavour retention during drying (and storage for cinnamaldehyde), whereas >= 50% of the flavour was lost when the flavour was O/W emulsified with a surfactant and then freeze-dried with sugar. (C) 2015 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.foodchem.2015.11.097

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  • The Use of a Proteinaceous “Cushion” with a Polystyrene-Binding Peptide Tag to Control the Orientation and Function of a Target Peptide Adsorbed to a Hydrophilic Polystyrene Surface 査読

    Hiroyuki Imanaka, Daisuke Yamadzumi, Keisuke Yanagita, Naoyuki Ishida, Kazuhiro Nakanishi an, Koreyoshi Imamura

    Biotechnology Progress32 ( 2 ) 527 - 534   2016年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1002/btpr.2232

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  • Nanostructures of 2-Aminopropyltriethoxysilane Created on Flat Substrate by Combining Colloid Lithography and Vapor Deposition 査読

    Naoyuki Ishida, Ryohei Nishihara, Hiroyuki Imanaka, Koreyoshi Imamura

    Colloids and Surfaces B: Biointerfaces147   9 - 16   2016年

  • Inhibitory effects of additives and heat treatment on the crystallization of freeze-dried sugar 査読

    Kohshi Kinugawa, Mitsunori Kinuhata, Ryo Kagotani, Hiroyuki Imanaka, Naoyuki Ishida, Mizuki Kitamatsu, Kazuhiro Nakanishi, Koreyoshi Imamura

    JOURNAL OF FOOD ENGINEERING155   37 - 44   2015年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCI LTD  

    An amorphous matrix of a sugar is frequently used as a bulk-forming and stabilizing agent in the food industry but tends to crystallize as the result of water uptake and increase in temperature. Additives and methods used to inhibit the crystallization of amorphous sugar (sucrose) were screened in this study. Freeze-dried amorphous sucrose containing 0.5-5 wt% of additive, including salts, different types of sugars, and polymers, the crystallization temperature (T-cry) and isothermal crystallization characteristics were examined. Certain types of salts markedly increased the Tcry and prolonged the induction period for crystal nucleation. The use of 1 wt% MgCl2 was particularly effective in inhibiting sugar crystallization. The heat treatment of crystalline sucrose under appropriate conditions was also found to result in diminished sucrose crystallization. MALDI-TOF mass spectra of the heat-treated sucrose suggested that sucrose derivatives containing multiple pyranose groups were formed, which would closely relate to the crystallization inhibition. Finally, the protein stabilizing effects of the matrices were evaluated. The results indicated that both the addition of additives and the heat treatment resulted in an improvement of the protein stabilizing effect of amorphous sugar matrix, compared to that of sucrose alone. (C) 2015 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.jfoodeng.2015.01.016

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  • Influence of sugar surfactant structure on the encapsulation of oil droplets in an amorphous sugar matrix during freeze-drying 査読

    Shota Nakayama, Yoshifumi Kimura, Sayuri Miki, Jun Oshitani, Takashi Kobayashi, Shuji Adachi, Tsutashi Matsuura, Hiroyuki Imanaka, Naoyuki Ishida, Hiroko Tada, Kazuhiro Nakanishi, Koreyoshi Imamura

    FOOD RESEARCH INTERNATIONAL70   143 - 149   2015年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    The encapsulation of O/W emulsion droplets in a freeze-dried amorphous sugar matrix was investigated, focusing on the impact of the molecular structure of the emulsifying surfactant. O/W emulsions, containing various surfactants, were freeze-dried in the presence of a sugar. Thirty types of surfactants, including eighteen different sugar surfactants and ten types of commercially available sugar ester mixtures, were used. Linoleic acid methyl ester and trehalose were used as the oil phase and sugar. The amounts of oil droplets encapsulated in freeze-dried amorphous sugar matrix were analyzed by Fourier transform Infrared spectroscopy. Sugar surfactants were generally superior to the other classes of surfactants for oil droplet encapsulation during freeze-drying, and there was the optimum alkyl chain length of the sugar surfactant. Sugar esters generally exhibited greater oil encapsulation than sugar ethers. Larger sugar head group appeared to result in better encapsulation in the case of sugar esters, but the opposite tendency was found for sugar ethers. A limited combination of sugar surfactants (15% sucrose mono- and 85% di-stearate) resulted in the maximum oil droplet encapsulation efficiency although these surfactants are individually quite poor in the encapsulation and other tested combinations did not improve the encapsulation efficiency relative to their individual effectiveness. (C) 2015 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.foodres.2015.02.003

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  • Characteristics of Sugar Surfactants in Stabilizing Proteins During Freeze?Thawing and Freeze‐Drying 査読

    Koreyoshi Imamura, Katsuyuki Murai, Tamayo Korehisa, Noriyuki Shimizu, Ryo Yamahira, Tsutashi, Matsuura, Hiroko Tada, Hiroyuki Imanaka, Naoyuki Ishida, Kazuhiro Nakanishi

    Journal of Pharmaceutical Sciences103 ( 6 ) 1628 - 1637   2014年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1002/jps.23988

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  • Polymorphobacter multimanifer gen. nov., sp nova, a polymorphic bacterium isolated from antarctic white rock 査読

    Wakao Fukuda, Yohzo Chino, Shigeo Araki, Yuka Kondo, Hiroyuki Imanaka, Tamotsu Kanai, Haruyuki Atomi, Tadayuki Imanaka

    INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY64 ( 6 ) 2034 - 2040   2014年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SOC GENERAL MICROBIOLOGY  

    A Gram-stain-negative, non-spore-forming, aerobic, oligotrophic bacterium (strain 262-7(T)) was isolated from a crack of white rock collected in the Skallen region of Antarctica. Strain 262-7(T) grew at temperatures between -4 and 30 degrees C, with optimal growth at 25 degrees C. The pH range for growth was between pH 6.0 and 9.0, with optimal growth at approximately pH 7.0. The NaCl concentration range allowing growth was between 0.0 and 1.0%, with an optimum of 0.5%. Strain 262-7(T) showed an unprecedented range of morphological diversity in response to growth conditions. Cells grown in liquid medium were circular or ovoid with smooth surfaces in the lag phase. In the exponential phase, ovoid cells With short projections were observed. Cells in the stationary phase possessed long tentacle-like projections intertwined intricately. By contrast, cells grown on agar plate medium or in liquid media containing organic compounds at low concentration exhibited short- and long-rod-shaped morphology. These projections and morphological variations clearly differ from those of previously described bacteria. Ubiquinone 10 was the major respiratory quinone. The major fatty acids were C-17:1 omega 6c (28.2%), C-16:1 omega 7c (22.6%), C-18:1 omega 7c (12.9%) and C(15:0)2-OH (12.3%). The G+C content of genomic DNA was 68.0 mol%. Carotenoids were detected from the cells. Comparative analyses of 16S rRNA gene sequences indicated that strain 262-7(T) belongs to the family Sphingomonadaceae, and that 262-7(T) should be distinguished from known genera in the family Sphingomonadaceae. According to the phylogenetic position, physiological characteristics and unique morphology variations, strain 262-7(T) should be classified as a representative of a novel genus of the family Sphingomonadaceae. Here, a novel genus and species with the name Polymorphobacter multimanifer gen. nov., sp. nov. is proposed (type strain 262-7(T)=JCM 18140(T)=ATCC BAA-2413(T)). The novel species was named after its morphological diversity and formation of unique projections.

    DOI: 10.1099/ijs.0.050005-0

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  • Effect of Surface Hydrophobicity on Short-Range Hydrophobic Attraction between Silanated Silica Surfaces 査読

    Yuuhei Soga, Hiroyuki Imanaka, Koreyoshi Imamura, Naoyuki Ishida

    Advanced Powder Technology51 ( 5 ) 343 - 348   2014年

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  • Improving the physical stability of freeze-dried amorphous sugar matrices by compression at several hundreds MPa 査読

    Ryo Kagotani, Kohshi Kinugawa, Mayo Nomura, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

    JOURNAL OF PHARMACEUTICAL SCIENCES102 ( 7 ) 2187 - 2197   2013年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-BLACKWELL  

    Amorphous matrices, composed of sugars, are markedly plasticized by moisture uptake, which results in physical instability. Our previous studies, in the compression pressure range 443 MPa, indicated that when a matrix is compressed, the amount of sorbed water at given relative humidities (RHs) decreases, whereas the glass transition temperature (Tg) remains constant. Herein, the effect of higher compression pressures than those used previously was explored to investigate the feasibility of using compression to improve the physical stability of amorphous sugar matrix against water uptake and subsequent collapse. Amorphous sugar samples were prepared by freeze-drying and then compressed at 0-665 MPa, followed by rehumidification at given RHs. The physical stability of the amorphous sugar sample was evaluated by measuring Tg and crystallization temperature (Tcry). The amounts of sorbed water, different in the interaction state, were determined using an FTIR technique. It was found that the compression at pressures of 443 MPa decreased the amount of sorbed water, which is a major factor in plasticization and crystallization, and thus markedly increased the Tg and Tcry relative to that for the uncompressed sample. Hence, the compression at several hundreds MPa appears to be feasible for improving the physical stability of amorphous sugar matrix. (c) 2013 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 102:2187-2197, 2013

    DOI: 10.1002/jps.23568

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  • Characteristics of amorphous matrices composed of different types of sugars in encapsulating emulsion oil droplets during freeze-drying 査読

    Koreyoshi Imamura, Yoshifumi Kimura, Shota Nakayama, Miki Sayuri, Seiji Ogawa, Tatsuya Hoshino, Jun Oshitani, Takashi Kobayashi, Shuji Adachi, Tsutashi Matsuura, Hiroyuki Imanaka, Naoyuki Ishida, Kazuhiro Nakanishi

    FOOD RESEARCH INTERNATIONAL51 ( 1 ) 201 - 207   2013年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    The encapsulation of emulsion oil droplets by amorphous sugar matrices, formed by freeze-drying, was investigated, with a focus on the influence of the type of sugar. An oil-in-water emulsion, comprised of linoleic acid methyl ester (LME) and sucrose monolaurate (SML) as an oil phase and surfactant, respectively, were freeze-dried in the presence of different types of sugars. LME-droplet encapsulation during and after freeze-drying were evaluated by FTIR analysis. The loss of LME largely occurred in the early stage of freeze-drying. The size distribution of the encapsulated LME droplets remained unchanged before and after freeze-drying in most cases. The encapsulated fractions of LME droplets could be correlated with the glass transition temperature of the sugars in the fully hydrated state (T-g*), and the existence of an optimum T-g* value for the sugar matrix was predicted. The encapsulation ability of an amorphous sugar matrix was maximized when mono- and polysaccharide were combined so as to give a value for T-g* of approximately -50 degrees C, although, individually, mono- and polysaccharides were quite poor for oil droplet encapsulation. These findings suggest that the structural flexibility of the amorphous sugar matrix is a major determinant in oil droplet encapsulation by an amorphous sugar matrix during freeze-drying. (C) 2012 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.foodres.2012.12.010

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  • The Discoidin Domain of Bacillus circulans β-Galactosidase Plays an Essential Role in Repressing Galactooligosaccharide Production 査読

    Jingyuan Song, Hiroyuki Imanaka, Koreyoshi Imamura, Masashi Minoda, Shotaro Yamaguchi an, Kazuhiro Nakanishi

    Bioscience Biotechnology and Biochemistry77 ( 1 ) 73 - 79   2013年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1271/bbb.120583

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  • Cloning and Expression of a β-Galactosidase Gene of Bacillus circulans 査読

    Jingyuan Song, Hiroyuki Imanaka, Koreyoshi Imamura, Masashi Minoda, Toru Katase, Yukiko Hoshi, Shotaro Yamaguchi, Kazuhiro Nakanishi

    Bioscience Biotechnology and Biochemistry75 ( 6 ) 1194 - 1197   2011年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1271/bbb.110014

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  • Causes of the Production of Multiple Forms of β-Galactosidase by Bacillus circulans 査読

    Jingyuan Song, Kiriko Abe, Hiroyuki Imanaka, Koreyoshi Imamura, Masashi Minoda, Shotaro, Yamaguchi, Kazuhiro Nakanishi

    Bioscience Biotechnology and Biochemistry75 ( 2 ) 268 - 278   2011年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1271/bbb.100574

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  • An archaeal 2-deoxyribose 4-phosphate aldolase that exhibits closer homology to bacteria rather than archaea 査読

    Naeem Rashid, Hiroyuki Imanaka, Tadayuki Imanaka

    Journal of Chemical Society of Pakistan30 ( 5 ) 740 - 749   2011年

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  • Development of a highly efficient indigo dyeing method using indican with an immobilized β-glucosidase from Aspergillus Niger 査読

    Jingyuan Song, Hiroyuki Imanaka, Koreyoshi Imamura, Kouichi Kajitani, Kazuhiro Nakanishi

    Journal of Bioscience and Bioengineering110 ( 3 ) 281 - 287   2010年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jbiosc.2010.03.010

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  • Cultivation characteristics and gene expression profiles of Aspergillus oryzae by membrane-surface liquid culture, shaking-flask culture, and agar-plate culture 査読

    Hiroyuki Imanaka, Soukichi Tanaka, Bin Feng, Koreyoshi Imamura, Kazuhiro Nakanishi

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING109 ( 3 ) 267 - 273   2010年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SOC BIOSCIENCE BIOENGINEERING JAPAN  

    We cultivated a filamentous fungus, Aspergillus oryzae IAM 2706 by three different cultivation methods, i.e., shaking-flask culture (SFC), agar-plate culture (APC), and membrane-surface liquid culture (MSLC), to elucidate the differences of its behaviors by different cultivation methods under the same media, by measuring the growth, secretion of proteases and alpha-amylase, secreted protein level, and gene transcriptional profile by the DNA microarray analysis. The protease activities detected by MSLC and APC were much higher than that by SFC, using both modified Czapek-Dox (mCD) and dextrin-peptone-yeast extract (DPY) media. The alpha-amylase activity was detected in MSLC and APC in a much larger extent than that in SFC when DPY medium was used. On the basis of SDS-PAGE analyses and N-terminal amino acid sequences, 6 proteins were identified in the supernatants of the culture broths using DPY medium, among which oryzin (alkaline protease) and alpha-amylase were detected at a much higher extent for APC and MSLC than those for SFC while only oryzin was detected in mCD medium, in accordance with the activity measurements. A microarray analysis for the fungi cultivated by SFC, APC, and MSLC using mCD medium was carried out to elucidate the differences in the gene transcriptional profile by the cultivation methods. The gene transcriptional profile obtained for the MSLC sample showed a similar tendency to the APC sample while it was quite different from that for the SFC sample. Most of the genes specifically transcribed in the MSLC sample versus those in the SFC sample with a 10-fold up-regulation or higher were unknown or predicted proteins. However, transcription of oryzin gene was only slightly up-regulated in the MSLC sample and that of alpha-amylase gene, slightly down-regulated. (C) 2009, The Society for Biotechnology, Japan. All rights reserved.

    DOI: 10.1016/j.jbiosc.2009.09.004

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  • Impacts of Compression on Crystallization Behavior of Freeze-Dried Amorphous Sucrose 査読

    Koreyoshi Imamura, Mayo Nomura, Kazuhiro Tanaka, Nobuhide Kataoka, Jun Oshitani, Hiroyuki Imanaka, Kazuhiro Nakanishi

    JOURNAL OF PHARMACEUTICAL SCIENCES99 ( 3 ) 1452 - 1463   2010年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:JOHN WILEY & SONS INC  

    An amorphous matrix comprised of sugar molecules is used as excipient and stabilizing agent for labile ingredients in the pharmaceutical industry. The amorphous sugar matrix is often compressed into a tablet form to reduce the volume and improve handling. Herein, the effect of compression on the crystallization behavior of an amorphous sucrose matrix was investigated. Amorphous sucrose samples were prepared by freeze-drying and compressed under different conditions, followed by analyses by differential scanning calorimetry, isothermal crystallization tests, X-ray powder diffractometry, Fourier transform infrared spectroscopy (FTIR), and gas pycnometry. The compressed sample had a lower crystallization temperature and a shorter induction period for isothermal crystallization, indicating that compression facilitates the formation of the critical nucleus of a sucrose crystal. Based on FTIR and molecular dynamics simulation results, the conformational distortion of sucrose molecules due to the compression appears to contribute to the increase in the free energy of the system, which leads to the facilitation of critical nucleus formation. An isothermal crystallization test indicated an increase in the growth rate of sucrose crystals by the compression. This can be attributed to the transformation of the microstructure from porous to nonporous, as the result of compression. (C) 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:1452-1463, 2010

    DOI: 10.1002/jps.21890

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  • Formation characteristics of calcium phosphate deposits on a metal surface by H2O2-electrolysis reaction under various conditions 査読

    Kazuaki Kanamoto, Koreyoshi Imamura, Nobuhide Kataoka, Jun Oshitani, Hiroyuki Imanaka, Kazuhiro Nakanishi

    COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS350 ( 1-3 ) 79 - 86   2009年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    The cathodic electrolysis of H2O2 (H2O2 + e(-) -> OH- + (OH)-O-center dot) on a metal surface in the presence of calcium and phosphate ions results in the formation of calcium phosphate deposits oil the metal surface. In this Study, the deposits formed under various treatment conditions (pHs, concentrations and ratios of calcium/phosphate ions, and so on) were characterized by scanning electron spectroscopy (SEM). and X-ray diffractometry. The exclusive formation of hydroxyapatite, HAP, was observed under comparatively narrow conditions (pH 3-4, [Ca+]/[PO43-] = 25 mM/15 mM), which is clearly different from the reported conditions for the deposition of HAP on titanium substrates. HAP was deposited in the form of a layer. comprised of morphologically amorphous HAP flakes that were less than 20 nm thick. SEM and FTIR analyses of the deposit at different stages of H2O2-electrolysis revealed that a few dozen nanometer-sized spheres of amorphous calcium phosphate were formed in the first step and then fused with each other to form ribbon-like flakes of HAP or broken glass-like brushite, depending on the pH. The pH for HAP formation oil a stainless steel surface was markedly lower than that used for titanium, and the observed process by which amorphous calcium phosphate is converted to HAP was markedly different from that for the electrochemical deposition (electrolysis of water) of HAP on a titanium substrate. (C) 2009 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.colsurfa.2009.09.007

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  • Purification, Characterization, Molecular Cloning, and Expression of a New Aminoacylase from Streptomyces mobaraensis That Can Hydrolyze N-(Middle/Long)-chain-fatty-acyl-L-amino Acids as Well as N-Short-chain-acyl-L-amino acids 査読

    Mayuko Koreishi, Yasuyuki Nakatani, Manami Ooi, Hiroyuki Imanaka, Koreyoshi Imamura, Kazuhiro Nakanishi

    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY73 ( 9 ) 1940 - 1947   2009年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

    We report here on the purification, characterization, molecular cloning, and expression of a new aminoacylase, initially isolated from the supernatant of Streptomyces mobaraensis (Sm-AA). Purified wild-type Sm-AA was found to be a monomeric protein with a molecular mass of 55kDa. The cloned gene of Sm-AA contained an ORF of 1,383 bp, encoding a polypeptide of 460 amino acids. A BLAST search revealed that Sm-AA belongs to the peptidase M20 family, with identities to a hypothetical protein from Streptomyces pristinaespiralis, a putative peptidase from Streptomyces averinitilis, peptidase M20 from Frankia sp., succinyl-diaminopimelate desuccinylase from Hemophilus influenzae, and aminoacylase-1 from porcine kidney at 89, 88, 67, 29, and 25% respectively. The Sm-AA gene was subcloned into an expression vector, pSH19, and was expressed in Streptomyces lividans TK24. The amount of the recombinant Sm-AA expressed in the S. lividans cells was approximately 42-fold higher than that of Sm-AA found in the supernatant of S. mobaraensis. Sm-AA showed high hydrolytic activity towards various N-acetyl-L-amino acids and N-(middle/long)-chain-fatty-acyl-L-amino acids, with a preference for the acyl derivatives of L-Met, L-Ala, L-Cys, etc. with an optimum pH and temperature for reaction of about 7.5 and 50 degrees C (at pH 7.5).

    DOI: 10.1271/bbb.90081

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  • Efficient N epsilon-lauroyl-L-lysine production by recombinant epsilon-lysine acylase from Streptomyces mobaraensis 査読

    Mayuko Koreishi, Ryoko Kawasaki, Hiroyuki Imanaka, Koreyoshi Imamura, Yasuaki Takakura, Kazuhiro Nakanishi

    JOURNAL OF BIOTECHNOLOGY141 ( 3-4 ) 160 - 165   2009年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    epsilon-Lysine acylase from Streptomyces mobaraensis (Sm-ELA), which specifically catalyzes hydrolysis of the epsilon-amide bond in various N epsilon-acyl-L-lysines, was cloned and sequenced. The Sm-ELA gene consists of a 1617-bp open reading frame that encodes a 538-amino acid protein with a molecular mass of 55,816 Da. An NCBI protein-protein BLAST search revealed that the enzyme belongs to the YtcJ-like metal-dependent amidohydrolase family, which is further characterized as the metallo-dependent hydrolase superfamily. The Sm-ELA gene was ligated into a pUC702 vector for expression in Streptomyces lividans TK24. Expression of recombinant Sm-ELA in S. lividans was approximately 300-fold higher than that in wild-type S. mobaraensis. The recombinant Sm-ELAs from the cell-free extract and Culture supernatant were purified to homogeneity. The specific activities of the purified Sm-ELAs were 2500-2800 U/mg, which were similar to that obtained for the wild-type Sm-ELA. Using the cell-free extract of the recombinant S. lividans cells, N epsilon-lauroyl-L-lysine was synthesized from 500 mM L-lysine hydrochloride and 50, 100, or 250 mM lauric acid in an aqueous buffer Solution at 37 degrees C. The yields were close to 100% after 6 and 9 1) of reaction for 50 and 100 mM lauric acid, respectively. and 90% after 24 h for 250 mM lauric acid. (C) 2009 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.jbiotec.2009.03.008

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  • Development of peptide immobilization method using PS-tagged cushion protein 査読

    Hiroyuki Imanaka, Daisuke Yamazumi, Toshinobu Kunikata, Koreyoshi Imamura, Kazuhiro, Nakanishi

    Journal of Bioscience and Bioengineering108   2009年

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  • Efficient Ethanol Production from Wheat Bran by Enzymatic Saccharification Using Commercially Available Enzyme Products and Fermentation Using Bakers' Yeast 査読

    Mayuko Koreishi, Hiroyuki Imanaka, Koreyoshi Imamura, Masahiro Kariyama, Kazuhiro Nakanishi

    Seibutsu-kogaku Kaishi87 ( 5 ) 216 - 223   2009年

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  • Recent advances in controlled immobilization of proteins onto the surface of the solid substrate and its possible application to proteomics 査読

    Kazuhiro Nakanishi, Takaharu Sakiyama, Yoichi Kumada, Koreyoshi Imamura, Hiroyuki Imanaka

    Current Proteomics5 ( 3 ) 161 - 175   2008年10月

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    記述言語:英語  

    Proteome analysis plays a key role in the elucidation of the functions and applications for numerous proteins. For proteome analyses, various microplate- and microarray-based techniques have been developed by a number of researchers. Their intent was to immobilize proteins on the surface of a solid substrate in a site-directed manner while retaining structure and native biological function. In this review, we focus on recent advances in immobilization methodology for proteins/enzymes on a surface, including those using the affinity peptides screened by random peptide library systems. We also discuss applications of the affinity peptide-mediated immobilization method in fields related to proteome analysis, particularly our recent work concerning immunoassay and protein-protein interaction analysis. ©2008 Bentham Science Publishers Ltd.

    DOI: 10.2174/157016408785909622

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  • True density analysis of a freeze-dried amorphous sugar matrix 査読

    Koreyoshi Imamura, Yoshinobu Maruyama, Kazuhiro Tanaka, Tohru Yokoyama, Hiroyuki Imanaka, Kazuhiro Nakanishi

    JOURNAL OF PHARMACEUTICAL SCIENCES97 ( 7 ) 2789 - 2797   2008年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:JOHN WILEY & SONS INC  

    True density of an amorphous matrix represents the state of molecular packing in the matrix, which is closely related to the physical/chemical properties of the material. Dry gas pycnometry is one possible technique for measuring the true density of an amorphous sugar matrix prepared by freeze-drying. We herein report on the influence of conditions used for pycnometry on the measured density value and propose a protocol for obtaining the true density. The technique is sufficiently accurate to permit values for matrices comprised of different types of sugar to be compared. Using the protocol, the true densities of several amorphous sugar samples containing different types of sugar, freeze-drying conditions (temperature and sugar concentration at the time of freezing of an aqueous sugar solution), pretreatment (compaction and grind) were determined and the results were compared. A model for simulating an amorphous matrix of sugar (trehalose) was constructed using molecular dynamics/mechanics calculations, and the true density of the simulated sugar matrix was found to agree with the value experimentally determined using the proposed protocol. The relationship among the true density, the states of intermolecular interactions, and strain of sugar molecules in the matrix are discussed using the simulated amorphous sugar matrix. (C) 2007 Wiley-Liss, Inc.

    DOI: 10.1002/jps.21202

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  • Temperature scanning FTIR analysis of interactions between sugar and polymer additive in amorphous sugar-polymer mixtures 査読

    Koreyoshi Imamura, Ken-Ichi Ohyama, Toru Yokoyama, Yoshinobu Maruyama, Hiroyuki Imanaka, Kazuhiro Nakanishi

    JOURNAL OF PHARMACEUTICAL SCIENCES97 ( 1 ) 519 - 528   2008年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:JOHN WILEY & SONS INC  

    The impact of a polymer additive (polyvinylpyrrolidone, PVP) on hydrogen bonding in amorphous sugar matrices as well as on the glass transition temperature, T-g, were examined by temperature scanning Fourier transform infrared spectroscopy (TS-FTIR). An amorphous sugar matrix containing PVP was prepared by air-drying an aqueous solution of a sugar-PVP mixture. The hydrogen bonds in the sugar-PVP mixture (sugar-PVP and sugar-sugar hydrogen bonds) were analyzed from the IR peak positions corresponding to the stretching vibration of C=O groups of PVP and O-H groups of the sugar and the temperature dependence of the peak position of the O-H stretching vibration band. The addition of PVP to amorphous mono and disaccharides significantly lowered the extent of hydrogen bond formation while interactions between sugars and the PVP tended to prevent the disruption of hydrogen bonds due to increasing temperature, the magnitude of which was larger for larger oligomers. The T-g value for the amorphous sugar was increased by the addition of PVP in many cases. As the size of sugar molecule became larger, the relative magnitude of the increased T-g by PVP to the difference between the T-g values for sugar alone and PVP alone became larger and then reached a certain level; it was slight in the case of glucose. Collectively, these results demonstrate that the magnitude of the impact of PVP on an amorphous sugar matrix strongly vary and are dependent on the types of sugar. (C) 2007 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97:519-528, 2008.

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  • Fourier self-deconvolution analysis of hydrogen bonding states of polyvinylpyrrolidone in an amorphous sugar matrix below and above the glass transition temperature 査読

    Koreyoshi Imamura, Ken-ichi Ohyama, Kazuko Tani, Toru Yokoyama, Yoshinobu Maruyama, Hiroyuki Imanaka, Kazuhiro Nakanishi

    SPECTROSCOPY LETTERS41 ( 6 ) 305 - 312   2008年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS INC  

    In an amorphous mixture of sugar and polyvinylpyrrolidone (PVP), PVP carbonyl groups form hydrogen bonds with sugar hydroxyl groups, thereby improving the physical stability of the amorphous matrix against a glass-to-rubber transition. Herein, Fourier self-deconvolved IR bands due to the C=O stretching vibration of PVP in sugar-PVP mixtures were analyzed. The C=O groups in sugar-PVP mixtures generally had four vibrational states, corresponding with free and hydrogen-bonded C=O in three different modes. Changes in these vibrational states induced by increasing the temperature were compared among various sugar-PVP mixtures. Formation and thermal disruption characteristics of different modes of sugar-PVP hydrogen bondings are discussed.

    DOI: 10.1080/00387010802370959

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  • TPR domain of Ser/Thr phosphatase of Aspergillus oryzae shows no auto-inhibitory effect on the dephosphorylation activity 査読

    Bin Feng, Chun-Hui Zhao, Soukichi Tanaka, Hiroyuki Imanaka, Koreyoshi Imamura, Kazuhiro Nakanishi

    INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES41 ( 3 ) 281 - 285   2007年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    A Ser/Thr phosphatase gene cloned from Aspergillus oryzae, aoppt, revealed that the tetratricopeptide repeat (TPR) and catalytic domains of the full-length AoPPT are located at the N- and C-terminal regions, respectively, similar to those of human Ser/Thr phosphatase 5 (PP5) and yeast Ppt1. Four different regions of AoPPT, namely, a full-length polypeptide, the catalytic domain, the catalytic domain plus C-terminal 15 amino-acid residues and the TPR domain were expressed in Escherichia coli and their roles in dephosphorylation activity were examined, using p-nitrophenyl phosphate as the substrate. The full-length AoPPT showed the highest dephosphorylation activity while the catalytic domain had the lowest activity. The activity of the catalytic domain was not inhibited by the presence of the TPR domain and arachidonic acid did not increase the activity of the full-length enzyme. These findings suggest that the integrity of the entire enzyme would be necessary for its full activity to be expressed. (c) 2007 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.ijbiomac.2007.03.005

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  • Enzymatic synthesis of beta-lactam antibiotics and N-fatty-acylated amino compounds by the acyl-transfer reaction catalyzed by penicillin V acylase from Streptomyces mobaraensis 査読

    Mayuko Koreishi, Kazuha Tani, Yuuichi Ise, Hiroyuki Imanaka, Koreyoshi Imamura, Kazuhiro Nakanishi

    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY71 ( 6 ) 1582 - 1586   2007年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

    Penicillin V acylase from Streptomyces mobaraensis (Sm-PVA) showed high acyl-transfer activity in reactions using methyl esters of carboxylic acid (acyl donor) and amino compounds (nucleophile), to produce the corresponding amides. Moreover, Sm-PVA had broad substrate specificity, as indicated by the fact that it catalyzed the efficient synthesis of fl-lactam antibiotics, capsaicin derivatives, and N-fatty-acyl-amino acid/N-fatty-acyl-peptide derivatives.

    DOI: 10.1271/bbb.70052

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  • Cloning and characterization of penicillin V acylase from Streptomyces mobaraensis 査読

    Demin Zhang, Mayuko Koreishi, Hiroyuki Imanaka, Koreyoshi Imamura, Kazuhiro Nakanishi

    JOURNAL OF BIOTECHNOLOGY128 ( 4 ) 788 - 800   2007年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    We report on the molecular cloning and characterization of penicillin V acylase (PVA) from an actinomycete, Streptomyces mobaraensis (Sm-PVA), which was originally isolated as an acylase that efficiently hydrolyzes the amide bond of various N-fatty-acyl-L-amino acids and N-fatty-acyl-peptides as well as capsaicin (8-methyl-N-vanillyl-6-nonenamide). In addition, the purified Sm-PVA hydrolyzed penicillin V with the highest activity (k(cat)) among the PVAs so far reported, penicillin G, and 2-nitro-5-phenoxyacetamide benzoic acid. The BLAST search revealed that the Sm-PVA precursor is composed of a polypeptide that is characteristic of enzymes belonging to the beta-lactam acylase family with four distinct segments; a signal sequence (43 amino acids), an a subunit (173 amino acids), a linker peptide (28 amino acids), and a beta subunit (570 amino acids). The mature, active Sm-PVA is a heterodimeric protein with alpha and beta subunits, in contrast to PVAs isolated from Bacillus sphaericus and B. subtilis, which have a homotetrameric structure. The amino acid sequence of Sm-PVA showed identities to PVA from S. lavendulae, N-acylhomoserine lactone-degrading acylase from Streptomyces sp., cyclic lipopeptide acylase from Streptomyces sp., and aculeacin A acylase from Actinoplanes utahensis with 68, 67, 67, and 41% identities, respectively. (c) 2007 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.jbiotec.2006.12.017

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  • Protein-protein interaction analysis using an affinity peptide tag and hydrophilic polystyrene plate 査読

    Yoichi Kumada, Chunhui Zhao, Ryota Ishimura, Hiroyuki Imanaka, Koreyoshi Imamura, Kazuhiro Nakanishi

    JOURNAL OF BIOTECHNOLOGY128 ( 2 ) 354 - 361   2007年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    A sandwich ELISA method using peptide tags showing a specific affinity to a hydrophilic polystyrene surface (PS-tags), PS 19 composed of RAFIASRRIKRP and KPS19R10 of KRAFIASRRIRRP and a hydrophilic polystyrene (phi-PS) plate was used to analyze protein-protein interactions. An Escherichia coli cysteine synthase complex, in which serine acetyltransferase (SAT) interacts with O-acetylserine sulfhydrylase-A (OASS) was used as a model system. When the interaction was detected by the conventional sandwich ELISA method using a hydrophobic polystyrene (pho-PS) plate, for the exclusive use of ELISA, the signal intensity was barely detectable due to conformational change of the ligand protein, OASS in the adsorbed state. On the contrary, when OASS, genetically fused with PS19 (OASS-PS19) or chemically conjugated with KPS19R10 (OASS-KPS19R10), was immobilized on the phi-PS plate, a high signal intensity was detected. Furthermore, by applying the two-step sandwich ELISA, in which OASS-PS19 or OASS-KPS19R10 formed a complex with SAT in the blocking solution before immobilization on the phi-PS plate, the signal intensity was further increased with a much shorter operational time, because SAT in the blocking solution formed a complex with OASS-PS19 or OASS-KPS19R10 without any steric hindrance. (c) 2006 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.jbiotec.2006.09.018

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  • Development of a one-step ELISA method using an affinity peptide tag specific to a hydrophilic polystyrene surface 査読

    Yoichi Kumada, Shigeo Katoh, Hiroyuki Imartaka, Koreyoshi Imamura, Kazuhiro Nakanishi

    JOURNAL OF BIOTECHNOLOGY127 ( 2 ) 288 - 299   2007年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    Glutathione S-transferase genetically fused with an affinity peptide tag, PS 19 (RAFIASRRIKRP) having a specific affinity for a hydrophilic polystyrene (PS) surface, was preferentially immobilized on a hydrophilic PS (phi-PS) plate without suffering from interference by coexisting protein molecules. Furthermore, rabbit IgG chemically conjugated with a peptide, KPS 19R10, in which (10)Lys in PS 19 was replaced with Arg and one Lys residue was added at the N-terminus as a coupling site for glutaraldehyde, showed a higher immobilization affinity to the phi-PS plate than that conjugated with the PS 19 peptide. On the basis of these findings, the use of a phi-PS plate and peptide tag-linked ligand proteins permitted a one-step or two-step enzyme-linked immumosorbent assay (ELISA) to be achieved, resulting in a substantial reduction in operational time compared with the conventional ELISA method using a hydrophobic PS (pho-PS) plate, while maintaining a high sensitivity. Furthermore, the sensitivity was increased to a greater extent compared to the conventional ELISA meihod when the one-step ELISA was applied to the detection of bovine insulin in a sandwich mode, due to the reduced number of washing and incubation steps. The method proposed here would be a versatile method for use in various ELISA techniques such as sandwich and competitive ELISAs using an antigen, an antibody and streptavidin that are genetically fused or chemically conjugated with the PS-specific affinity peptide as the ligand protein. (c) 2006 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.jbiotec.2006.07.011

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  • Identification of genes from Aspergillus oryzae that are preferentially expressed in membrane-surface liquid culture 査読

    Bin Feng, Masakazu Morita, Hiroyuki Imanaka, Koreyoshi Imamura, Kazuhlro Nakanishi

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING102 ( 5 ) 470 - 473   2006年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SOC BIOSCIENCE BIOENGINEERING JAPAN  

    We identified 22 genes from Aspergillus oryzae that are preferentially expressed in membrane-surface liquid culture (MSLC), among which Ser/Thr protein kinase (aopk1) and phosphatase (aoppt) genes were cloned. We also revealed that aopk1 encodes a protein with an N-terminal sequence 150 amino acid residues longer than that predicted from the registered sequence in GenBank.

    DOI: 10.1263/jbb.102.470

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  • Temperature scanning FTIR analysis of hydrogen bonding states of various saccharides in amorphous matrixes below and above their glass transition temperatures 査読

    Koreyoshi Imamura, Keisuke Sakaura, Ken-ichi Ohyama, Atsushi Fukushima, Hiroyuki Imanaka, Takaharu Sakiyama, Kazuhiro Nakanishi

    JOURNAL OF PHYSICAL CHEMISTRY B110 ( 31 ) 15094 - 15099   2006年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    Temperature scanning Fourier transform infrared, TS-FTIR, spectroscopy of various amorphous sugar matrixes was conducted to investigate the relationship between the glass transition temperature, T-g, of an amorphous sugar matrix and the nature of the hydrogen bonds in the matrix. An amorphous sugar matrix was prepared by air-drying an aqueous solution of sugar, and the degree of formation of hydrogen bonds in the matrix was evaluated at different temperatures using the peak positions of the IR band corresponding to the O-H stretching vibration at around 3400 cm(-1). The T-g value increased with increasing peak position of the O-H stretching vibration at T-g and were correlated reasonably well with the magnitude of the peak shift by the temperature increase (from 25 degrees C) to the T-g value. This demonstrates that the amorphous sugar matrix, in which the segments are fixed by fewer hydrogen bonds, has a higher thermal resistance. The glycosidic linkage largely contributes to the restriction of the segments, pyranose ring, rather than a hydrogen bond. As the degree of polymerization of pyranose rings increases, the degree of hydrogen bond formation needed to hold the matrix in a fixed position decreases. However, the magnitude of the restriction of pyranose rings by a glycosidic linkage changes depending on the type: the restrictions imposed by alpha-1,1 and -1,6 glycosidic linkages are the tightest and most flexible of all of the types of glycosidic linkages, respectively.

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  • Phosphoenolpyruvate synthase plays an essential role for glycolysis in the modified Embden-Meyerhof pathway in Thermococcus kodakarensis 査読

    Hiroyuki Imanaka, Atsushi Yamatsu, Toshiaki Fukui, Haruyuki Atomi, Tadayuki Imanaka

    MOLECULAR MICROBIOLOGY61 ( 4 ) 898 - 909   2006年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:BLACKWELL PUBLISHING  

    We have carried out a genetic analysis on pyruvate kinase (Pyk(Tk)) and phosphoenolpyruvate synthase (Pps(tk)) in the hyperthermophilic archaeon, Thermococcus kodakarensis. In principle, both enzymes can catalyse the final step of the modified Embden-Meyerhof (EM) pathway found in Thermococcales, the conversion of phosphoenolpyruvate (PEP) to pyruvate, with the former utilizing ADP, while the latter is dependent on AMP and phosphate. Enzyme activities and transcript levels of both Pyk(Tk) and Pps(Tk) increased in T. kodakarensis under glycolytic conditions when compared with cells grown on pyruvate or amino acids. Using KW128, a tryptophan auxotrophic mutant with a trpE gene disruption, as a host strain, we obtained mutant strains with single gene disruptions in either the pyk(Tk) (Delta pyk strain) or pps(Tk) (Delta pps strain) gene. Specific growth rates and cell yields were examined in various media and compared with the host KW128 strain. The results indicated that both enzymes participated in pyruvate metabolism, but were not essential. In the presence of maltooligosaccharides, the Delta pyk strain displayed a 15% decrease in growth rate compared with the host strain, indicating that Pyk(Tk) does participate in glycolysis. However an even more dramatic effect was observed in the Delta pps strain in that the strain could not grow at all on maltooligosaccharides. The results clearly indicate that, in contrast to the conventional EM pathway dependent on pyruvate kinase, PEP synthase is the essential enzyme for the glycolytic conversion of PEP to pyruvate in T. kodakarensis. The physiological roles of the two enzymes under various growth conditions are discussed.

    DOI: 10.1111/j.1365-2958.2006.05287.x

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  • Cloning, overexpression, purification, and characterization of O-acetylserine sulfhydrylase-B from Escherichia coli 査読

    C Zhao, Y Kumada, H Imanaka, K Imamura, K Nakanishi

    PROTEIN EXPRESSION AND PURIFICATION47 ( 2 ) 607 - 613   2006年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ACADEMIC PRESS INC ELSEVIER SCIENCE  

    O-Acetylserine sulfhydrylase-B (OASS-B, EC 2.5.1.47) is one of the two isozymes produced by Escherichia coli that catalyze the synthesis Of L-Cysteine from O-acetyl- L-serine and sulfide. The cysM gene encoding OASS-B was cloned and the enzyme was overexpressed in E coli using pUC19 with a lacUV5 promoter. The enzyme was purified to homogeneity, as evidenced by SDS-PAGE. Approximately 300 mg of purified OASS-B was obtained from 1600 mL of culture broth with a purification yield of 60% or higher. The purified OASS-13 was characterized and its properties compared with OASS-A. OASS-13 did not form a complex with E. coli serine acetyltransferase (SAT, EC 2.3.1.30) and showed a wide range of substrate specificity in nonproteinaceous amino acid synthesis. (c) 2006 Elsevier Inc. All rights reserved.

    DOI: 10.1016/j.pep.2006.01.002

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  • On the interaction site of serine acetyltransferase in the cysteine synthase complex from Escherichia coli 査読

    CH Zhao, Y Moriga, B Feng, Y Kumada, H Imanaka, K Imamura, K Nakanishi

    BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS341 ( 4 ) 911 - 916   2006年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ACADEMIC PRESS INC ELSEVIER SCIENCE  

    Cysteine synthase from Escherichia coli is a bienzyme complex comprised of serine acetyltransferase (SAT) and O-acetylserine sulfhydrylase A. The site of interaction of a SAT molecule was investigated by gel chromatography and surface plasmon technique using various mutant-type SATs, to better understand the mechanism involved in complex formation. The C-terminus of SAT, Ile 273, along with Glu 268 and Asp 271, was found to be essential for complex formation. The effects of O-acetyl-L-serine and sulfide on the affinity for the complex formation were also studied using a surface plasmon technique. (c) 2006 Elsevier Inc. All rights reserved.

    DOI: 10.1016/j.bbrc.2006.01.054

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  • Screening and characterization of affinity peptide tags specific to polystyrene supports for the orientated immobilization of proteins 査読

    Y Kumada, Y Tokunaga, H Imanaka, K Imamura, T Sakiyama, S Katoh, K Nakanishi

    BIOTECHNOLOGY PROGRESS22 ( 2 ) 401 - 405   2006年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    Dodecapeptides that exhibit a high affinity specific to a polystyrene surface (PS-tags) were screened using an Escherichia coli random peptide display library system, and the compounds were used as a peptide tag for the site-specific immobilization of proteins. The various PS-tags obtained after 10 rounds of biopanning selection were mainly composed of basic and aliphatic amino acid residues, most of which were arranged in close proximity to one another. Mutant-type glutathione S-transferases (GSTs) fused with the selected PS-tags. PS19 (RAFIASRRIKRP) and PS23 (AGLRLKKAAIHR) at their C-terminus, GST-PS19 and GST-PS23, when adsorbed on the PS latex beads had a higher affinity than the wild-type GST, and the specific remaining activity of the immobilized mutant-type GSTs was approximately 10 times higher than that of the wild-type GST. The signal intensity detected for GST-PS19 and GST-PS23 adsorbed on hydrophilic and hydrophobic PS surfaces using an anti-peptide antibody specific for the N-terminus peptide of GST was much higher than that for the wild-type GST. These findings indicate that the mutant-type GSTs fused with the selected peptide tags, PS19 and PS23, could be site-specifically immobilized on the surface of polystyrene with their N-terminal regions directed toward the solution. Thus, the selected peptide tags would be useful for protein immobilization in the construction of enzyme-linked immunosorbent assay (ELISA) systems and protein-based biochips.

    DOI: 10.1021/bp050331l

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  • A novel acylase from Streptomyces mobaraensis that efficiently catalyzes hydrolysis/synthesis of capsaicins as well as N-Acyl-L-amino acids and N-acyl-peptides 査読

    M Koreishi, DM Zhang, H Imanaka, K Imamura, S Adachi, R Matsuno, K Nakanishi

    JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY54 ( 1 ) 72 - 78   2006年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    A novel enzyme that catalyzes efficient hydrolysis of capsaicin (8-methyl-N-vanillyl-6-nonenamide) was isolated from the culture broth of Streptomyces mobaraensis. The enzyme consisted of two dissimilar subunits with molecular masses of 61 and 19 kDa. The enzyme was activated and stabilized in the presence of Co2+. It showed a pH optimum of about 8 and was stable at temperatures of up to 55 degrees C for 1 h at pH 7.8. The specific activity of the enzyme for the hydrolysis of capsaicin was 10(2)-10(4) times higher than those for the enzymes reported to date. In an aqueous/n-hexane biphasic system, capsaicin analogues such as octanoyl, decanoyl, and lauroyl vanillylamides were synthesized from the corresponding fatty acids and vanillylamine at yields of 50% or greater. In addition, the enzyme catalyzed the deacylation of N-lauroyl-L-amino acids and N-lauroyl-L-dipeptides and the efficient synthesis of N alpha-lauroyl-L-lysine, N epsilon-lauroyl-L-lysine, and various N-lauroyl-peptides in aqueous solution in both the absence and the presence of glycerol.

    DOI: 10.1021/jf052102k

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  • Purification and characterization of a novel aminoacylase from Streptomyces mobaraensis 査読

    M Koreishi, F Asayama, H Imanaka, K Imamura, M Kadota, T Tsuno, K Nakanishi

    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY69 ( 10 ) 1914 - 1922   2005年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

    A novel aminoacylase was purified to homogeneity from culture broth of Streptomyces mobaraensis, as evidenced by SDS-polyacrylamide gel electrophoresis (PAGE). The enzyme was a monomer with an approximate molecular mass of 100 kDa. The purified enzyme was inhibited by the presence of 1,10-phenanthroline and activated by the addition of Co2+. It was stable at temperatures of up to 60 degrees C for 1 h at pH 7.2. It showed broad substrate specificity to N-acetylated L-amino acids. It catalyzed the hydrolysis of the amide bonds of various N-acetylated L-amino acids, except for N epsilon-acetyl-L-lysine and N-acetyl-L-proline. Hydrolysis of N-acetyl-L-methionine and N-acetyl-L-histidine followed Michaelis-Menten kinetics with K-m values of 1.3 +/- 0.1 mm and 2.7 +/- 0.1 mm respectively. The enzyme also catalyzed the deacetylation of 7-aminocephalosporanic acid (7-ACA) and cephalosporin C. Moreover, feruloyl-amino acids and L-lysine derivatives of ferulic acid derivatives were synthesized in an aqueous buffer using the enzyme.

    DOI: 10.1271/bbb.69.1914

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  • A novel ε-lysine acylase from Streptomyces mobaraensis for synthesis of Nε-acyl-L-lysines 査読

    Mayuko Koreishi, Ryoko Kawasaki, Hiroyuki Imanaka, Koreyoshi Imamura, Kazuhiro Nakanishi

    Journal of the American Oil Chemists’ Society82 ( 9 ) 631 - 637   2005年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1007/s11746-005-1121-2

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  • Continuous hydrogen production by the hyperthermophilic archaeon, Thermococcus kodakaraensis KOD1 査読

    T Kanai, H Imanaka, A Nakajima, K Uwamori, Y Omori, T Fukui, H Atomi, T Imanaka

    JOURNAL OF BIOTECHNOLOGY116 ( 3 ) 271 - 282   2005年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    The hydrogen (H-2) production potential of the hyperthermophilic archaeon, Thermococcus kodakaraensis KOD1 was evaluated at 85 degreesC. In batch cultivation using a complex medium supplemented with elemental sulfur (S-0), evolution of H2S and CO2 was observed in the gas phase. When So was omitted and pyruvate or starch was added in the medium, the cells produced H-2 at high levels instead of H2S. As the level of H-2 appeared to correlate with the specific growth rate, analysis in continuous cultures was performed to develop a continuous H-2 production system. In a steady-state condition at a dilution rate of 0.2 h(-1), a continuous H-2 production rate (per gram dry weight, gdw) of 24.9 and 14.0 mmol gdw(-1) h(-1) was observed in media supplemented with pyruvate and starch, respectively. In both cultivations, a high accumulation of acetate and alanine was found as metabolites. When the dilution rates were elevated in the medium with pyruvate, steady-state growth was observed up to 0.8 h(-1), and a maximum H-2 production rate of 59.6 mmol gdw(-1) h(-1) was obtained. Based on the experimental results along with data of the entire genome sequence, the metabolic pathway of the strain relating to starch and pyruvate degradation is discussed. (C) 2004 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.jbiotec.2004.11.002

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  • Genetic evidence identifying the true gluconeogenic fructose-1,6-bisphosphatase in Thermococcus kodakaraensis and other hyerthermophiles. 査読

    T Sato, H Imanaka, N Rashid, T Fukui, H Atomi, T Imanaka

    JOURNAL OF BACTERIOLOGY186 ( 17 ) 5799 - 5807   2004年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER SOC MICROBIOLOGY  

    Fructose-1,6-bisphosphatase (FBPase) is one of the key enzymes in gluconeogenesis. Although FBPase activity has been detected in several hyperthermophiles, no orthologs corresponding, to the classical FBPases from bacteria and eukaryotes have been identified in their genomes. An inositol monophosphatase (IMPase) from Methanococcus jannaschii which displayed both FBPase and IMPase activities and a structurally novel FBPase (Fbp(Tk)) from the hyperthermophilic archaeon Thermococcus kodakaraensis KOD1 have been proposed as the "missing" FBPase. For this study, using T. kodakaraensis, we took a genetic approach to elucidate which candidate is the major gluconeogenic enzyme in vivo. The IMPase/FBPase ortholog in T. kodakaraensis, Imp(Tk), was confirmed to possess high FBPase activity along with IMPase activity, as in the case of other orthologs. We therefore constructed Deltafbp and Deltaimp strains by applying a gene disruption system recently developed for T. kodakaraensis and investigated their phenotypes. The Deltafbp strain could not grow under gluconeogenic conditions while glycolytic growth was unimpaired, and the disruption resulted in the complete abolishment of intracellular FBPase activity. Evidently, fbp(Tk) is an indispensable gene for gluconeolgenesis and is responsible for almost all intracellular FBPase activity. In contrast, the endogenous imp(Tk) gene could not complement the defect of the fbp deletion, and its disruption did not lead to any detectable phenotypic changes under the conditions examined. These facts indicated that imp(Tk) is irrelevant to gluconeogenesis, despite the high FBPase activity of its protein product, probably due to insufficient transcription. Our results provide strong evidence that the true FBPase for gluconeogenesis in T. kodakaraensis is the FbpTk ortholog, not the IMPase/FBPase ortholog.

    DOI: 10.1128/JB.186.17.5799-5807.2004

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  • Presence of a novel phosphopentomutase and a 2-deoxyribose 5-phosphate aldolase reveals a metabolic link between pentoses and central carbon metabolism in the hyperthermophilic archaeon Thermococcus kodakaraensis 査読

    N Rashid, H Imanaka, T Fukui, H Atomi, T Imanaka

    JOURNAL OF BACTERIOLOGY186 ( 13 ) 4185 - 4191   2004年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER SOC MICROBIOLOGY  

    Numerous bacteria and mammalian cells harbor two enzymes, phosphopentomutase (PPM) and 2-deoxyribose 5-phosphate aldolase (DERA), involved in the interconversion between nucleosides and central carbon metabolism. In this study, we have examined the presence of this metabolic link in the hyperthermophilic archaeon, Thermococcus kodakaraensis KOD1. A search of the genome sequence of this strain revealed the presence of a closely related orthologue (TK2104) of bacterial DERA genes while no orthologue related to previously characterized PPM genes could be detected. Expression, purification, and characterization of the TK2104 protein product revealed that this gene actually encoded a DERA, catalyzing the reaction through a class I aldolase mechanism. As PPM activity was detected in T. kodakaraensis cells, we partially purified the protein to examine its N-terminal amino acid sequence. The sequence corresponded to a gene (TK1777) similar to phosphomannomutases within COG1109 but not COG1015, which includes all previously identified PPMs. Heterologous gene expression of TK1777 and characterization of the purified recombinant protein clearly revealed that the gene indeed encoded a PPM. Both enzyme activities could be observed in T. kodakaraensis cells under glycolytic and gluconeogenic growth conditions, whereas the addition of ribose, 2-deoxyribose, and 2'-deoxynucleosides in the medium did not lead to a significant induction of these activities. Our results clearly indicate the presence of a metabolic link between pentoses and central carbon metabolism in T. kodakaraensis, providing an alternative route for pentose biosynthesis through the functions of DERA and a structurally novel PPM.

    DOI: 10.1128/JB.186.13.4185-4191.2004

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  • Gene cloning and characterization of fructose-1,6-bisphosphate aldolase from the hyperthermophilic archaeon Thermococcus kodakaraensis KOD1 査読

    H Imanaka, T Fukui, H Atomi, T Imanaka

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING94 ( 3 ) 237 - 243   2002年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SOC BIOSCIENCE BIOENGINEERING JAPAN  

    The fructose-1,6-bisphosphate (FBP) aldolase gene from the hyperthermophilic archaeon Thermococcus kodakaraensis KOD1 was cloned. The gene encoding FBP aldolase (Tk-fba) was expressed in Escherichia coli and the purified recombinant protein was characterized at high temperature. Tk-Fba is a homodecamer with a subunit molecular mass of 31,283 Da. The amino acid sequence, decameric conformation, formation of a Schiff-base intermediate, and stimulation (286%) of FBP cleavage activity by citrate suggested that Tk-Fba belonged to Class IA, a subtype of the classical Class I aldolases. The specific activity for the FBP cleavage reaction was 18.9 U/mg, which was much higher than those of other Class IA type FBP aldolases. Tk-Fba was extremely thermostable since the optimum temperature seemed to be above 100degreesC. The optimum pH for Tk-Fba was determined to be 5.0 in the absence of citrate, while it shifted to around 7.0 in the presence of citrate. Tk-Fba accepted FBP and fructose-1-phosphate as substrates and K-m values were determined to be 0.063 mM and 4.37 mM, respectively. In addition to citrate, phosphoenolpyruvate and pyrophosphate were also found to be potent activators of Tk-Fba, enhancing activities up to 346% and 201%, respectively. Erythrose-4-phosphate acted as an inhibitor and caused a decrease in the activity to 49%. Tk-Fba also catalyzed the condensation reaction with a similar activity level (14.9 U/mg) to that for FBP cleavage. However, none of the above compounds seemed to have a significant effect on the condensation reaction by Tk-Fba. These results suggest a regulatory function of Tk-Fba toward the catabolic direction of sugar metabolism in T. kodakaraensis KOD1.

    DOI: 10.1263/jbb.94.237

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  • A novel candidate for the true fructose-1,6-bisphosphatase in Archaea 査読

    N Rashid, H Imanaka, T Kanai, T Fukui, H Atomi, T Imanaka

    JOURNAL OF BIOLOGICAL CHEMISTRY277 ( 34 ) 30649 - 30655   2002年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC  

    Fructose-1,6-bisphosphatase (FBPase) is one of the key enzymes of the gluconeogenic pathway. Although enzyme activity had been detected in Archaea, the corresponding gene had not been identified until a presumable inositol monophosphatase gene from Methanococcus jannaschii was found to encode a protein with both inositol monophosphatase and FBPase activities. Here we display that a gene from the hyperthermophilic archaeon, Thermococcus kodakaraensis KOD1, which does not correspond to the inositol monophosphatase gene from M. jannaschii, displays high FBPase activity. The FBPase from strain KOD1 was partially purified, its N-terminal amino acid sequence was determined, and the gene (Tk-fbp) was cloned. Tk-fbp encoded a protein of 375 amino acid residues with a molecular mass of 41,658 Da. The recombinant Tk-Fbp was purified and characterized. Tk-Fbp catalyzed the conversion of fructose 1,6-bisphosphate to fructose 6-phosphate following Michaelis-Menten kinetics with a K-m value of 100 mum toward fructose 1,6-bisphosphate, and a k(cat) value of 17 s(-1) subunit(-1) at 95degreesC. Unlike the inositol monophosphatase from M. jannaschii, Tk-Fbp displayed strict substrate specificity for fructose 1,6-bisphosphate. Activity was enhanced by Mg2+ and dithioerythritol, and was slightly inhibited by fructose 2,6-bisphosphate. AMP did not inhibit the enzyme activity. We examined whether expression of Tk-fbp was regulated at the transcription level. High levels of Tk-fbp transcripts were detected in cells grown on pyruvate or amino acids, whereas no transcription was detected when starch was present in the medium. Orthologue genes corresponding to Tk-fbp with high similarity are present in all the complete genome sequences of thermophilic Archaea, including M. jannaschii, Pyrococcus furiosus, Sulfolobus solfataricus, and Archaeoglobus fulgidus, but are yet to be assigned any function. Taking into account the high FBPase activity of the protein, the strict substrate specificity, and its sugar-repressed gene expression, we propose that Tk-Fbp may represent the bona fide FBPase in Archaea.

    DOI: 10.1074/jbc.M202868200

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  • Removal of aromatic compounds in gas by electron attachment 査読

    H Tamon, H Imanaka, N Sano, M Okazaki, W Tanthapanichakoon

    INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH37 ( 7 ) 2770 - 2774   1998年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    A corona-discharge reactor was applied to remove benzene and p-dichlorobenzene from nitrogen and a nitrogen-oxygen mixture. Although benzene was not effectively removed from nitrogen by electron attachment, the removal efficiency was improved greatly by mixing oxygen. On the other hand, the high removal efficiencies of p-dichlorobenzene were obtained in nitrogen or a nitrogen-oxygen mixture. The removal mechanism was studied based on the contribution of the ozone reaction and the analysis of the deposit on the anode of the reactor. As a result, the ozone reaction does not contribute to the removals. An FT-IR measurement and thermogravimetry suggest that benzene or p-dichlorobenzene is decomposed by dissociative electron attachment and deposits as polycyclic aromatic compounds of a high boiling point on the anode surface.

    DOI: 10.1021/ie980071v

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書籍等出版物

  • バイオ実験を安全に行うために

    今中 洋行( 担当: 分担執筆 ,  範囲: 5章 情報の保管と管理 pp.108-110)

    化学同人  2018年 

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  • 細胞・生体分子の固定化と機能発現

    今中 洋行( 担当: 分担執筆 ,  範囲: 第6章 クッションタンパク質を用いたリガンド分子固定化法の開発と利用)

    シーエムシー出版  2018年 

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  • Encyclopedia of Industrial Biotechnology : Bioprocess, Bioseparation, and Cell Technology (ed. by M.C. Flickinger)

    ( 担当: 分担執筆 ,  範囲: Chapter: Membrane-Surface Liquid Culture, Fungi)

    Wiley  2009年 

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  • 第5版実験化学講座29 -バイオテクノロジーの基本技術-

    丸善  2006年 

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MISC

  • 続・生物工学基礎講座 バイオよもやま話 定量的分子間相互作用解析のススメ(前編)

    今中洋行

    生物工学会誌96 ( 5 ) 266‐269   2018年5月

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    記述言語:日本語  

    J-GLOBAL

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  • コドンが決め手!?組換えタンパク質の高発現法 招待

    今中洋行

    生物工学会誌91 ( 11 ) 655 - 655   2013年

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  • Isolation and Characterization of a Thermostable Monoacylglycerol Lipase from Soil Bacterium

    Hiroyuki Imanaka, Masashi Mori, Koreyoshi Imamura, Takaharu Sakiyama, Kazuhiro Nakanishi

    Proceedings for Asia-Pacific Biochemical Engineering Conference (APBioChEC’04)   2005年

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  • Biochemical and genetic analyses on enzymes involved in central carbon metabolism in the hyperthermophilic archaeon, Thermococcus kodakaraensis

    Haruyuki Atomi, Takaaki Sato, Hiroyuki Imanaka, Wakao Fukuda, Naeem Rashid, Toshiaki Fukui, Tadayuki Imanaka

    Proceedings for International Symposium on Extremophiles and their Applications   2005年

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  • Complete genome analysis and development of gene disruption technology in the hyperthermophilic archaeon, Thermococcus kodakaraensis

    Tadayuki Imanaka, Toshiaki Fukui, Takaaki Sato, Hiroyuki Imanaka, Rie Matsumi, Haruyuki Atomi

    Proceedings for the 2004 International Symposium on Micro-NanoMechatronics and Human Science   2005年

  • オーソログ遺伝子による分類の限界?−始原菌の例− 招待

    今中洋行

    生物工学会誌82 ( 8 ) 342 - 342   2004年

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講演・口頭発表等

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産業財産権

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受賞

  • 農芸化学会中四国支部奨励賞

    2013年  

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    受賞国:日本国

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  • Outstanding Young Scientist and Student Award

    2011年  

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    受賞国:日本国

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  • Best Poster Presentation Award

    2010年  

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担当授業科目

  • 先端材料プロセス化学 (2020年度) 前期  - 金1,金2

  • 実践応用化学 (2020年度) 前期  - その他

  • 応用化学ゼミナール1 (2020年度) 前期  - その他

  • 応用化学ゼミナール2 (2020年度) 後期  - その他

  • 応用化学特別研究 (2020年度) 通年  - その他

  • 数理・データサイエンスの基礎 (2020年度) 第3学期  - 月1,月2

  • 材料プロセス実験2 (2020年度) 第1学期  - 月4,月5,月6,月7,木4,木5,木6,木7

  • 材料プロセス実験2 (2020年度) 第1学期  - 月4,月5,月6,月7,木4,木5,木6,木7

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