Yuta Murai

Research Faculty of Agriculture　Fundamental AgriScience Research　Applied BioscienceAssociate Professor
Institute for the Advancement of Higher EducationAssociate Professor
Last Updated :2025/03/18

■Researcher basic information

Researchmap personal page

Home Page URL

Researcher number

  • 20707038

ORCID ID

J-Global ID

Research Keyword

  • infertility treatment
  • sphingolipid
  • Alzheimer's disease
  • 生物有機化学
  • 光アフィニティーラベル法
  • ケミカルバイオロジー

Research Field

  • Life sciences, Bioorganic chemistry

Educational Organization

■Career

Career

  • Apr. 2023 - Present
    Hokkaido University, Graduate School of Agriculture Research Faculty of Agriculture, 准教授
  • May 2020 - Mar. 2023
    理化学研究所, 客員研究員
  • Aug. 2013 - Mar. 2023
    Hokkaido University, Faculty of Advanced Life Science, 助教
  • Apr. 2013 - Jul. 2013
    Ritsumeikan University, 総合科学研究機構, 博士研究員

Educational Background

  • Apr. 2010 - Mar. 2013, Hokkaido University, Graduate School of Agriculture, 応用生物科学専攻

■Research activity information

Awards

  • Mar. 2024, 日本農芸化学会, 2024年度農芸化学奨励賞　　　　　　　　　　　　　　　
  • Feb. 2024, 日本化学会北海道支部, 日本化学会北海道支部奨励賞　　　　　　　　　　　　　　　
  • Nov. 2023, セラミド研究会, Young Investigator Award　　　　　　　　　　　　　　　

Papers

  • Malabaricone C isolated from edible plants as a potential inhibitor of SARS-CoV-2 infection.
    Mutmainah, Yuta Murai, Ai Fujimoto, Rintaro Kawamura, Akira Kitamura, Sajeer Koolath, Seigo Usuki, Michihito Sasaki, Yasuko Orba, Yasuyuki Igarashi, Hirofumi Sawa, Akihiko Sato, Kenji Monde
    Scientific reports, 15, 1, 8518, 8518, 12 Mar. 2025, [Peer-reviewed], [Corresponding author], [International Magazine]
    English, Scientific journal, Although the SARS-CoV-2 epidemic worldwide has gradually decreased, in some areas, the situation has not yet been stamped and has become a global health emergency. It is quite possible that we could again be threatened by a new coronavirus. Therefore, new nucleotide analog drugs and vaccines or using drug repositioning for SARS-CoV-2 still has been developed, yet their safety and efficacy against COVID-19 remains underexplored. Malabaricone C is 2,6-dihydroxyphenyl acylphenol found in edible plants such as the mace spice of nutmeg derived from the seeds of Myristica fragrans. In this study, we identified malabaricone C as the first inhibitor of SARS-CoV-2 from natural food with a safe alternative for drugs. Malabaricone C and its chemical derivatives showed EC50 values of 1-1.5 μM against SARS-CoV-2 (WK-521, ancestral strain) and its variant strains in mammalian cells (HEK293T and Vero E6). In addition, we have successfully established novel evaluation system for the inhibition of SARS virus cell fusion by visualization for providing a versatile tool for study SARS-CoV-2 mediated fusion. Furthermore, our experiments suggested that malabaricone C could affect the distribution of sphingomyelin on the plasma membrane, which involves in viral infections. Thus, in light of the beneficial effect of malabaricone C on viral infection, the nontoxic malabaricone C is a suitable candidate as a drug that can be employed in the treatment and prevention of COVID-19. Moreover, it may potentially be used to treat acute infections of other enveloped viruses.
  • Scalable preparation of furanosteroidal viridin, β-viridin and viridiol from Trichoderma virens
    Wen Zhang, Kazu Sunami, Shuo Liu, Desita Triana, Zetryana Puteri Tachrim, Rikuto Kikuchi, Tohru Taniguchi, Kenji Monde, Tsunayoshi Takehara, Da-Yang Zhou, Takeyuki Suzuki, Yasuyuki Hashidoko, Makoto Hashimoto, Yuta Murai
    Scientific Reports, 15, 1, Springer Science and Business Media LLC, 24 Jan. 2025, [Peer-reviewed], [Last author, Corresponding author]
    Scientific journal
  • Elucidation of physiological functions of sphingolipid-related molecules by chemical approaches
    Yuta Murai
    Bioscience, Biotechnology, and Biochemistry, 24 Jan. 2025, [Peer-reviewed], [Lead author, Corresponding author]
    Scientific journal
  • A Review of Cinnamic Acid’s Skeleton Modification: Features for Antibacterial-Agent-Guided Derivatives
    Rose Malina Annuur, Desita Triana, Teni Ernawati, Yuta Murai, Muhammad Aswad, Makoto Hashimoto, Zetryana Puteri Tachrim
    Molecules, 29, 16, 3929, 3929, MDPI AG, 20 Aug. 2024, [Peer-reviewed]
    Scientific journal, Antimicrobial resistance has emerged as a significant danger to global health, and the need for more effective antimicrobial resistance (AMR) control has been highlighted. Cinnamic acid is abundant in plant products and is a potential starting material for further modification, focusing on the development of new antimicrobial compounds. In the following review, we describe the classification of critical antibacterial-guided reactions applied to the main skeleton structure of cinnamic acid derivatives over the last decade. Of all of the main parts of cinnamic acids, the phenyl ring and the carboxylic group significantly affect antibacterial activity. The results presented in the following review can provide valuable insights into considerable features in the organic modification of cinnamic acids related to antibacterial medication development and the food industry.
  • Biocompatible and Water-Soluble Shortwave-Infrared (SWIR)-Emitting Cyanine-Based Fluorescent Probes for In Vivo Multiplexed Molecular Imaging
    Mahadeva M. M. Swamy, Yuta Murai, Kenji Monde, Setsuko Tsuboi, Aravind K. Swamy, Takashi Jin
    ACS Applied Materials & Interfaces, 10 Apr. 2024, [Peer-reviewed]
    Scientific journal
  • Racemization of the substrate and product by serine palmitoyltransferase from Sphingobacterium multivorum yields two enantiomers of the product from d-serine
    Hiroko Ikushiro, Takumi Honda, Yuta Murai, Taiki Murakami, Aya Takahashi, Taiki Sawai, Haruna Goto, Shin-ichi Ikushiro, Ikuko Miyahara, Yoshio Hirabayashi, Nobuo Kamiya, Kenji Monde, Takato Yano
    Journal of Biological Chemistry, Mar. 2024, [Peer-reviewed], [Corresponding author]
    Scientific journal
  • Accumulation of squalene in filamentous fungi Trichoderma virens PS1-7 in the presence of butenafine hydrochloride, squalene epoxidase inhibitor. -Biosynthesis of 13C-enriched squalene
    Wen Zhang, Kazu Sunami, Shuo Liu, Zihan Zhuang, Yasuko Sakihama, Da-Yang Zhou, Takeyuki Suzuki, Yuta Murai, Makoto Hashimoto, Yasuyuki Hashidoko
    Bioscience, Biotechnology, and Biochemistry, Oxford University Press (OUP), 01 Aug. 2023, [Peer-reviewed], [Corresponding author]
    Scientific journal, Abstract

    Squalene is a triterpenoid compound and widely used in various industries such as medicine and cosmetics due to its strong antioxidant and anticancer properties. The purpose of this study is to increase the accumulation of squalene in filamentous fungi using exogeneous butenafine hydrochloride, which is an inhibitor for squalene epoxidase. The detailed settings achieved that the filamentous fungi, Trichoderma virens PS1-7, produced squalene up to 429.93 ± 51.60 mg/L after culturing for 7 days in the medium consisted of potato infusion with glucose at pH 4.0, in the presence of 200 μM butenafine. On the other hand, no squalene accumulation was observed without butenafine. This result indicated that squalene was biosynthesized in the filamentous fungi PS1-7 which can be used as a novel source of squalene. In addition, we successfully obtained highly 13C-enriched squalene by using [U-13C6]-glucose as a carbon source replacing normal glucose.
  • Structural insights into the substrate recognition of serine palmitoyltransferase from Sphingobacterium multivorum
    Hiroko Ikushiro, Taiki Murakami, Aya Takahashi, Asuka Katayama, Taiki Sawai, Haruna Goto, Sajeer Koolath, Yuta Murai, Kenji Monde, Ikuko Miyahara, Nobuo Kamiya, Takato Yano
    Journal of Biological Chemistry, 299, 5, 104684, 104684, Elsevier BV, May 2023, [Peer-reviewed]
    Scientific journal
  • Stereochemistry‐activity relationship of ceramide‐induced exosome production to clear amyloid‐β in Alzheimer's disease
    Mariam Abdelrasoul, Kohei Yuyama, Mahadeva M. M. Swamy, Yuta Murai, Kenji Monde
    Chirality, 35, 9, 577, 585, Wiley, 13 Apr. 2023, [Peer-reviewed]
    Scientific journal, Abstract

    Stereochemistry has a substantial impact on the biological activity of various drugs. We investigated the role of stereochemistry of ceramides in inducing the production of exosomes, a type of extracellular vesicle, from neuronal cells, with a potential benefit in improving the clearance of amyloid‐β (Aβ), a causal agent of Alzheimer's disease. A stereochemical library of diverse ceramides with different tail lengths was synthesized with the purpose of varying stereochemistry (D‐erythro: DE, D‐threo: DT, L‐erythro: LE, L‐threo: LT) and hydrophobic tail length (C6, C16, C18, C24). The exosome levels were quantified using TIM4‐based exosome enzyme‐linked immunosorbent assay after concentrating the conditioned medium using centrifugal filter devices. The results revealed a pivotal role of stereochemistry in determining the biological activity of ceramide stereoisomers, with the superiority of those based on DE and DT stereochemistry with C16 and C18 tails, which demonstrated significantly higher exosome production, without a significant change in the particle size of the released exosomes. In transwell experiments with Aβ‐expressed neuronal and microglial cells, DE‐ and DT‐ceramides with C16 and C18 tails significantly decreased extracellular Aβ levels. The results reported here are promising in the design of non‐classic therapies for the treatment of Alzheimer's disease.
  • Heteroaromatic Diazirines Are Essential Building Blocks for Material and Medicinal Chemistry.
    Yuta Murai, Makoto Hashimoto
    Molecules (Basel, Switzerland), 28, 3, 01 Feb. 2023, [Peer-reviewed], [Lead author, Corresponding author], [International Magazine]
    English, Scientific journal, In materials (polymer) science and medicinal chemistry, heteroaromatic derivatives play the role of the central skeleton in development of novel devices and discovery of new drugs. On the other hand, (3-trifluoromethyl)phenyldiazirine (TPD) is a crucial chemical method for understanding biological processes such as ligand-receptor, nucleic acid-protein, lipid-protein, and protein-protein interactions. In particular, use of TPD has increased in recent materials science to create novel electric and polymer devices with comparative ease and reduced costs. Therefore, a combination of heteroaromatics and (3-trifluoromethyl)diazirine is a promising option for creating better materials and elucidating the unknown mechanisms of action of bioactive heteroaromatic compounds. In this review, a comprehensive synthesis of (3-trifluoromethyl)diazirine-substituted heteroaromatics is described.
  • Stereochemistry of Sphingolipids in Ganglioside GM3 Enhances Recovery of Nervous Functionality
    Sajeer Koolath, Yuta Murai, Tomoya Suzuki, Mahadeva M, M. Swamy, Seigo Usuki, Kenji Monde
    ACS Med. Chem. Lett., 9, 1237, 1241, American Chemical Society (ACS), 2023, [Peer-reviewed], [Corresponding author]
    English, Scientific journal
  • Evaluation of Plant Ceramide Species-Induced Exosome Release from Neuronal Cells and Exosome Loading Using Deuterium Chemistry
    Yuta Murai, Takumi Honda, Kohei Yuyama, Daisuke Mikami, Koichi Eguchi, Yuichi Ukawa, Seigo Usuki, Yasuyuki Igarashi, Kenji Monde
    International Journal of Molecular Sciences, 23, 18, 10751, 10751, MDPI AG, 15 Sep. 2022, [Peer-reviewed], [Lead author, Corresponding author]
    Scientific journal, The extracellular accumulation of aggregated amyloid-β (Aβ) in the brain leads to the early pathology of Alzheimer’s disease (AD). The administration of exogenous plant-type ceramides into AD model mice can promote the release of neuronal exosomes, a subtype of extracellular vesicles, that can mediate Aβ clearance. In vitro studies showed that the length of fatty acids in mammalian-type ceramides is crucial for promoting neuronal exosome release. Therefore, investigating the structures of plant ceramides is important for evaluating the potential in releasing exosomes to remove Aβ. In this study, we assessed plant ceramide species with D-erythro-(4E,8Z)-sphingadienine and D-erythro-(8Z)-phytosphingenine as sphingoid bases that differ from mammalian-type species. Some plant ceramides were more effective than mammalian ceramides at stimulating exosome release. In addition, using deuterium chemistry-based lipidomics, most exogenous plant ceramides were confirmed to be derived from exosomes. These results suggest that the ceramide-dependent upregulation of exosome release may promote the release of exogenous ceramides from cells, and plant ceramides with long-chain fatty acids can effectively release neuronal exosomes and prevent AD pathology.
  • Hydrogen-deuterium exchange of indole-3-propionic acid with deuterated trifluoromethanesulfonic acid
    Wen Zhang, Zetryana Puteri Tachrim, Yurika Tokoro, Zeping Wang, Shoko Ishikawa, Yuta Murai, Takeyuki Suzuki, Makoto Hashimoto
    Arkivoc, 2022, 9, 33, 39, ARKAT USA, Inc., 31 Aug. 2022, [Peer-reviewed]
    Scientific journal
  • Penta-deuterium-labeled 4E, 8Z-sphingadienine for rapid analysis in sphingolipidomics study.
    Yuta Murai, Kohei Yuyama, Daisuke Mikami, Yasuyuki Igarashi, Kenji Monde
    Chemistry and physics of lipids, 245, 105202, 105202, 22 Mar. 2022, [Peer-reviewed], [Lead author, Corresponding author], [International Magazine]
    English, Scientific journal, The use of deuterium-incorporated bioactive compounds is an efficient method for tracing their metabolic fate and for quantitative analysis by mass spectrometry without complicated HPLC separation even if their amounts are extremely small. Plant sphingolipids and their metabolites, which have C4, 8-olefins on a common backbone as a sphingoid base, show unique and fascinating bioactivities compared to those of sphingolipids in mammals. However, the functional and metabolic mechanisms of exogenous plant sphingolipids have not been elucidated due to the difficulty in distinguishing exogenous sphingolipids from endogenous sphingolipids having the same polarity and same molecular weight by mass spectrometric analysis. Their roles might be elucidated by the use of deuterated probes with original biological and physicochemical properties. In this study, we designed (2S,3R,4E,8Z)-2-aminooctadeca-4,8-diene-17,17,18,18,18-d5-1,3-diol (penta-deuterium-labeled 4E, 8Z-sphingadienine) as a tracer for exogenous metabolic studies. In addition, the sphingadienine was confirmed to be metabolized in HEK293 cells and showed distinct peaks in mass spectrometric analysis.
  • Evaluation of chiral N,N-dimethyl-sphingosine for the interaction between nerve growth factor and tropomyosin receptor kinase A.
    Yuta Murai, Akihiro Sekiguchi, Taeko Hirakawa, Seigo Usuki, Yasuyuki Igarashi, Kenji Monde
    Chirality, 16 Mar. 2022, [Peer-reviewed], [Lead author, Corresponding author], [International Magazine]
    English, Scientific journal, Neuropathic pain is an unbearable condition caused by nervous system damage. As distinct acute pain, neuropathic pain is chronic, and it severely influences quality of life. N,N-Dimethyl-d-erythro-sphingosine (DMS), a neuropathic pain inducer, is metabolited de novo from sphingosine. In a recent study, metabolomics showed an increased concentration level of DMS in the spinal cord in mice with neuropathic pain. Nerve growth factor (NGF) is one of the peripheral nervous system targeted pain factors that interact with tropomyosin receptor kinase A (trkA). On the basis of this information, we were interested in the possibility that DMS may induce neuropathic pain-like behavior through an increase of NGF activity. In this study, we showed that DMS can enhance the binding of NGF to trkA, followed by neurite outgrowth of epidermal nerve fibers and phosphorylation of trkA. In addition, a stereoisomer, N,N-dimethyl-l-erythro-sphingosine, did not any show such biological activities. The results suggest that DMS can enhance the binding of NGF to trkA and that its stereochemistry is an essential factor for exhibiting its activity.
  • Shortwave-infrared (SWIR) emitting annexin V for high-contrast fluorescence molecular imaging of tumor apoptosis in living mice
    Mahadeva M. M. Swamy, Setsuko Tsuboi, Yuta Murai, Kenji Monde, Takashi Jin
    RSC Advances, 12, 30, 19632, 19639, Royal Society of Chemistry (RSC), 2022, [Peer-reviewed]
    Scientific journal, The labelling of annexin V with indocyanine green (ICG) and π-conjugation extended ICG (ICG-C11) resulted in SWIR emitting probes that enable high-contrast molecular imaging of tumor apoptosis in living mice.
  • A near-infrared fluorescent long-chain fatty acid toward optical imaging of cardiac metabolism in living mice
    Mahadeva M. M. Swamy, Mohamad Zarif Mohd Zubir, Mutmainah, Setsuko Tsuboi, Yuta Murai, Kenji Monde, Ken-ichi Hirano, Takashi Jin
    The Analyst, 147, 19, 4206, 4212, Royal Society of Chemistry (RSC), 2022, [Peer-reviewed]
    Scientific journal, A near infrared fluorescence labelled long-chain fatty acid (FFA), Alexa680-BMPP (BMPP: 15-(4-(3-aminopropyl)phenyl)-3-methyl pentadecanoic acid), was synthesized as a fluorescent probe toward optical imaging of cardiac metabolism.
  • Novel Synthesis and Properties of Optically Pure N-Trifluoroacetylphenylglycine Hydroxysuccinimide Ester
    Makoto Hashimoto, Zeping Wang, Shoko Ishikawa, Fumina Ohashi, Reo Sagisaka, Yuta Murai, Zetryana Puteri Tachrim, Takeyuki Suzuki
    HETEROCYCLES, 105, 1, 406, 406, The Japan Institute of Heterocyclic Chemistry, 2022, [Peer-reviewed]
    Scientific journal
  • Design and Synthesis of 1,3-Bis(3-(trifluoromethyl)diazirin-3-yl)phenylalanine for Efficient Photo Cross-Linking
    Yuta Murai, Makoto Hashimoto, Takuma Yoshida, Zetryana Puteri Tachrim
    HETEROCYCLES, 104, 1, 167, 167, The Japan Institute of Heterocyclic Chemistry, 2022, [Peer-reviewed], [Lead author, Corresponding author]
    Scientific journal
  • Shortwave-Infrared Fluorescent Molecular Imaging Probes Based on π-Conjugation Extended Indocyanine Green.
    Mahadeva M M Swamy, Yuta Murai, Kenji Monde, Setsuko Tsuboi, Takashi Jin
    Bioconjugate chemistry, 32, 8, 1541, 1547, 18 Aug. 2021, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Recently, shortwave-infrared (SWIR) fluorescence imaging for the optical diagnostics of diseases has attracted much attention as a new noninvasive imaging modality. For this application, the development of SWIR molecular imaging probes with high biocompatibility is crucial. Although many types of biocompatible SWIR fluorescent probes based on organic dyes have been reported, there are no SWIR-emitting molecular imaging probes that can be used for the detection of specific biomolecules in vivo. To apply SWIR-emitting molecular imaging probes to biomedical fields, we developed a biocompatible SWIR fluorescent dye based on π-conjugation extended indocyanine green (ICG), where ICG is the only approved near-infrared dye by the US Food and Drug Administration (FDA) for use in the clinic. Using the π-conjugation extended ICG, we prepared SWIR molecular imaging probes that can be used for in vivo tumor imaging. Herein, we demonstrate noninvasive SWIR fluorescence imaging of human epidermal growth factor receptor 2 (HER2)-positive and epidermal growth factor receptor (EGFR)-positive breast tumors using π-conjugation extended ICG and monoclonal antibody conjugates. The presented π-conjugation extended ICG analog probes will be a breakthrough to apply SWIR fluorescence imaging in biomedical fields.
  • New Trends in Diaziridine Formation and Transformation (a Review).
    Zetryana Puteri Tachrim, Lei Wang, Yuta Murai, Makoto Hashimoto
    Molecules (Basel, Switzerland), 26, 15, 26 Jul. 2021, [Peer-reviewed], [International Magazine]
    English, Scientific journal, This review focuses on diaziridine, a high strained three-membered heterocycle with two nitrogen atoms that plays an important role as one of the most important precursors of diazirine photoaffinity probes, as well as their formation and transformation. Recent research trends can be grouped into three categories, based on whether they have examined non-substituted, N-monosubstituted, or N,N-disubstituted diaziridines. The discussion expands on the conventional methods for recent applications, the current spread of studies, and the unconventional synthesis approaches arising over the last decade of publications.
  • Synthesis of (Trifluoromethyldiazirinyl)phenylboronic Acid Derivatives for Photoaffinity Labeling
    Makoto Hashimoto, Manami Hashinoki, Natsumi Kurokawa, Yuta Murai, Zetryana Puteri Tachrim, Yasuko Sakihama, Takeyuki Suzuki
    HETEROCYCLES, 103, 1, 392, 392, The Japan Institute of Heterocyclic Chemistry, 2021, [Peer-reviewed]
    Scientific journal
  • Daurichromenic Acid from the Chinese Traditional Medicinal Plant Rhododendron dauricum Inhibits Sphingomyelin Synthase and Aβ Aggregation
    Hadya Virupaksha Deepak, Mahadeva M. M. Swamy, Yuta Murai, Yoshiko Suga, Masaki Anetai, Takuro Yo, Masahiro Kuragano, Koji Uwai, Kiyotaka Tokuraku, Kenji Monde
    Molecules, 25, 18, 4077, 4077, MDPI AG, 07 Sep. 2020, [Peer-reviewed]
    Scientific journal, Species of the genus Rhododendron have been used in traditional Chinese medicine, with the medicinal herb “Manshanfong” used as an expectorant and for the treatment of acute bronchitis. Daurichromenic acid (DCA), a constituent of Rhododendron dauricum, is a meroterpenoid with antibacterial, anti-HIV, and anti-inflammatory activities. However, the mechanisms underlying these pharmacologic activities are poorly understood. To develop new drugs based on DCA, more information is required regarding its interactions with biomolecules. The present study showed that DCA inhibits the activity of the enzyme sphingomyelin synthase, with an IC50 of 4 µM. The structure–activity relationships between DCA and sphingomyelin synthase were evaluated using derivatives and cyclized hongoquercin A. In addition, DCA was found to inhibit amyloid β aggregation. These results may help in the design of effective drugs based on DCA.
  • Chiral combinatorial preparation and biological evaluation of unique ceramides for inhibition of sphingomyelin synthase.
    Sajeer Koolath, Yuta Murai, Yoshiko Suga, Kenji Monde
    Chirality, 32, 3, 308, 313, Mar. 2020, [Peer-reviewed], [Lead author], [International Magazine]
    English, Scientific journal, Enantiomers or diastereomers of chiral bioactive compounds often exhibit different biological and toxicological properties. Here, we report the efficient synthesis of four stereoisomers of sphingosine and derivatization of unique chiral ceramides through a combinatorial chemistry by solid-phase activated resin ester. In addition, to test the effectivity of stereochemistry of ceramide, we demonstrated a cell-based assay of sphingomyelin synthase inhibition in the presence ofchiral unique ceramides, which suggested that libraries of this sort will be a rich source of biologically active synthetic molecules.
  • Nrp1 is Activated by Konjac Ceramide Binding-Induced Structural Rigidification of the a1a2 Domain.
    Seigo Usuki, Yoshiaki Yasutake, Noriko Tamura, Tomohiro Tamura, Kunikazu Tanji, Takashi Saitoh, Yuta Murai, Daisuke Mikami, Kohei Yuyama, Kenji Monde, Katsuyuki Mukai, Yasuyuki Igarashi
    Cells, 9, 2, 24 Feb. 2020, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Konjac ceramide (kCer) is a plant-type ceramide composed of various long-chain bases and a-hydroxyl fatty acids. The presence of d4t,8t-sphingadienine is essential for semaphorin 3A (Sema3A)-like activity. Herein, we examined the three neuropilin 1 (Nrp1) domains (a1a2, b1b2, or c), and found that a1a2 binds to d4t,8t-kCer and possesses Sema3A-like activity. kCer binds to Nrp1 with a weak affinity of mM dissociation constant (Kd). We wondered whether bovine serum albumin could influence the ligand-receptor interaction that a1a2 has with a single high affinity binding site for kCer (Kd in nM range). In the present study we demonstrated the influence of bovine serum albumin. Thermal denaturation indicates that the a1a2 domain may include intrinsically disordered region (IDR)-like flexibility. A potential interaction site on the a1 module was explored by molecular docking, which revealed a possible Nrp1 activation mechanism, in which kCer binds to Site A close to the Sema3A-binding region of the a1a2 domain. The a1 module then accesses a2 as the IDR-like flexibility becomes ordered via kCer-induced protein rigidity of a1a2. This induces intramolecular interaction between a1 and a2 through a slight change in protein secondary structure.
  • Design and Synthesis of Ligand‐Tag Exchangeable Photoaffinity Probe Utilizing Nosyl Chemistry
    Aimi Suhaily Saaidin, Yuta Murai, Takuya Ishikawa, Kenji Monde
    European Journal of Organic Chemistry, 7563, 7567, 15 Dec. 2019, [Peer-reviewed], [Lead author]
    Scientific journal
  • Malabaricone C as Natural Sphingomyelin Synthase Inhibitor against Diet-Induced Obesity and Its Lipid Metabolism in Mice.
    Muhamad Aqmal Othman, Kohei Yuyama, Yuta Murai, Yasuyuki Igarashi, Daisuke Mikami, Yasodha Sivasothy, Khalijah Awang, Kenji Monde
    ACS medicinal chemistry letters, 10, 8, 1154, 1158, 08 Aug. 2019, [Peer-reviewed], [International Magazine]
    English, The interaction between natural occurring inhibitors and targeted membrane proteins could be an alternative medicinal strategy for the treatment of metabolic syndrome, notably, obesity. In this study, we identified malabaricones A-C and E (1-4) isolated from the fruits of Myristica cinnamomea King as natural inhibitors for sphingomyelin synthase (SMS), a membrane protein responsible for sphingolipid biosynthesis. Having the most promising inhibition, oral administration of compound 3 exhibited multiple efficacies in reducing weight gain, improving glucose tolerance, and reducing hepatic steatosis in high fat diet-induced obesity mice models. Liver lipid analysis revealed a crucial link between the SMS activities of compound 3 and its lipid metabolism in vitro and in vivo. The nontoxic nature of compound 3 makes it a suitable candidate in search of drugs which can be employed in the treatment and prevention of obesity.
  • Isolation and characterization of 1-palmitoyl-2-linoleoyl-sn-glycerol as a hormogonium-inducing factor (HIF) from the coralloid roots of Cycas revoluta (Cycadaceae).
    Yasuyuki Hashidoko, Hiroaki Nishizuka, Manato Tanaka, Kanako Murata, Yuta Murai, Makoto Hashimoto
    Scientific reports, 9, 1, 4751, 4751, 18 Mar. 2019, [Peer-reviewed], [International Magazine]
    English, Coralloid roots are specialized tissues of cycads (Cycas revoluta) that are involved in symbioses with nitrogen-fixing Nostoc cyanobacteria. We found that a crude methanolic extract of coralloid roots induced differentiation of the filamentous cell aggregates of Nostoc species into motile hormogonia. Hence, the hormogonium-inducing factor (HIF) was chased using bioassay-based isolation, and the active principle was characterized as a mixture of diacylglycerols (DAGs), mainly composed of 1-palmitoyl-2-linoleoyl-sn-glycerol (1), 1-palmitoyl-2-oleoyl-sn-glycerol (2), 1-stearoyl-2-linolenoyl-sn-glycerol (3), and 1-stearoyl-2-linoleoyl-sn-glycerol (4). Enantioselectively synthesised compound 1 showed a clear HIF activity at 1 nmol (0.6 µg) disc-1 for the filamentous cells, whereas synthesised 2-linoleoyl-3-palmitoyl-sn-glycerol (1') and 1-palmitoyl-2-linoleoyl-rac-glycerol (1/1') were less active than 1. Conversely, synthesised 1-linoleoyl-2-palmitoyl-rac-glycerol (8/8') which is an acyl positional isomer of compound 1 was inactive. In addition, neither 1-monoacylglycerols nor phospholipids structurally related to 1 showed HIF-like activities. As DAGs are protein kinase C (PKC) activators, 12-O-tetradecanoylphorbol-13-acetate (12), urushiol C15:3-Δ10,13,16 (13), and a skin irritant anacardic acid C15:1-Δ8 (14) were also examined for HIF-like activities toward the Nostoc cells. Neither 12 nor 13 showed HIF-like activities, whereas 14 showed an HIF-like activity at 1 nmol/disc. These findings appear to indicate that some DAGs act as hormogonium-inducing signal molecules for filamentous Nostoc cyanobacteria.
  • An automated microliter-scale high-throughput screening system (MSHTS) for real-time monitoring of protein aggregation using quantum-dot nanoprobes.
    Rina Sasaki, Reina Tainaka, Yuichi Ando, Yurika Hashi, Hadya V Deepak, Yoshiko Suga, Yuta Murai, Masaki Anetai, Kenji Monde, Kiminori Ohta, Ikuko Ito, Haruhisa Kikuchi, Yoshiteru Oshima, Yasuyuki Endo, Hitomi Nakao, Masafumi Sakono, Koji Uwai, Kiyotaka Tokuraku
    Scientific reports, 9, 1, 2587, 2587, 22 Feb. 2019, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Protein aggregation is the principal component of numerous protein misfolding pathologies termed proteinopathies, such as Alzheimer's disease, Parkinson's disease, prion disease, and AA amyloidosis with unmet treatment needs. Protein aggregation inhibitors have great potential for the prevention and treatment of proteinopathies. Here we report the development of an automated real-time microliter-scale high throughput screening (MSHTS) system for amyloid aggregation inhibitors using quantum-dot nanoprobes. Screening 504 crude extracts and 134 low molecular weight aromatic compounds revealed the relationship of amyloid-β (Aβ) aggregation inhibitory activities of plant extracts using a plant-based classification. Within the eudicots, rosids, Geraniales and Myrtales showed higher activity. Screening low molecular weight aromatic compounds demonstrated that the structure of tropolone endows it with potential Aβ aggregation inhibitory activity. The activity of the most active tropolone derivative was higher than that of rosmarinic acid. MSHTS also identified three chaperone molecules as tau aggregation inhibitors. These results demonstrate that our automated MSHTS system is a novel and robust tool that can be adapted to a wide range of compounds and aggregation-prone polypeptides.
  • Structure-inspired design of a sphingolipid mimic sphingosine-1-phosphate receptor agonist from a naturally occurring sphingomyelin synthase inhibitor.
    Mahadeva M M Swamy, Yuta Murai, Yusuke Ohno, Keisuke Jojima, Akio Kihara, Susumu Mitsutake, Yasuyuki Igarashi, Jian Yu, Min Yao, Yoshiko Suga, Masaki Anetai, Kenji Monde
    Chemical communications (Cambridge, England), 54, 90, 12758, 12761, 08 Nov. 2018, [Peer-reviewed], [Corresponding author], [International Magazine]
    English, Ginkgolic acid obtained as a sphingomyelin synthase inhibitor from a plant extract library inspired the concept of sphingolipid mimics. Ginkgolic acid-derived N-acyl anilines and ginkgolic acid 2-phosphate (GA2P) respectively mimic ceramide and sphingosine 1-phosphate (S1P) in structure and function. The GA2P-induced phosphorylation of ERK and internalization of S1P receptor 1 (S1P1) indicated potent agonist activity. Docking studies revealed that GA2P adopts a similar binding conformation to the bound ligand ML5, which is a strong antagonist of S1P1.
  • Facile Chemoselective Strategy toward Capturing Sphingoid Bases by a Unique Glutaraldehyde-Functionalized Resin.
    Siddabasave Gowda B Gowda, Atsufumi Nakahashi, Keiko Yamane, Saori Nakahashi, Yuta Murai, Ananda Kumar C Siddegowda, Mostafa A S Hammam, Kenji Monde
    ACS omega, 3, 1, 753, 759, 31 Jan. 2018, [Peer-reviewed], [International Magazine]
    English, Sphingoid bases, which have a 2-amino-1,3-diol common functional group, are the structural backbone units of all sphingolipids. Recently, much attention has been focused on sphingoid bases because of their potentially beneficial bioactivities toward various cancer cells as well as their dietary interest. However, low abundance and the handling complexity caused by their amphiphilic character led to very limited research on them. Glutaraldehyde has two aldehyde groups, and it reacts rapidly with the 2-amino-1,3-diol functional group of sphingosine to give a tricyclic product. Immobilization of glutaraldehyde on a resin was successfully performed by organic synthesis, starting from trans-p-coumaric acid via eight steps. This approach suppresses the self-polymerization of glutaraldehyde, and addition of water to the developed resin causes the formation of cyclic double hemiacetal function, which avoids oxidation like a reducing sugar in nature and makes it stable even for up to 1 year incubation. The resin was applied to the solid-phase extracting experiment of free sphingosine from human serum at a concentration of 280 nM. Another extraction study of edible golden oyster mushrooms showed that the sphingoid base was selectively captured from complex natural extracts. These results demonstrate that the developed glutaraldehyde resin method is a highly selective method, and hence, the combination of it with the o-phthaldialdehyde HPLC method was confirmed as an efficient and sensitive method for analysis of sphingoid bases in biological samples.
  • Synthesis of diazirinyl photophore and optically pure diazirinylphenylalanines for photoaffinity labeling
    Yuta Murai, Lei Wang, Makoto Hashimoto
    Photoaffinity Labeling for Structural Probing Within Protein, 111, 128, Springer Japan, 25 Sep. 2017, [Peer-reviewed], [Lead author, Corresponding author]
    English, In book, As photophores in photoaffinity labeling, three major types, arylazide, benzophenone, and diazirine have been used and contributed to the understanding of molecular biology processes. In particular, diazrine is a significantly useful photophore because it has some advantages such as its relatively small size, stability, low rate of rearrangement, and generating a high reactive carbene with longer wavelength which reduces damage to the target molecules. Nevertheless, despite these many advantages in diazirine, there are reports in which arylazide and benzophenone are generally utilized for photoaffinity labeling compared with diazirine due to its synthetic difficulty onto ligands. To overcome this problem, recently many researchers have addressed to establish the efficient synthetic route of diazirinyl compounds. Particularly, a-aromatic amino acids possess not only biological activities themselves but also basic component of protein (bioactive peptide). In addition, a number of heterocyclic bioactive compounds have variety of attractive biological activities. Therefore, their diazirinyl compounds promise the molecular biology processes. In this chapter, firstly, it is demonstrated the simple and efficient preparation of diazirine on aromatics and aliphatic chains. Furthermore post-functional derivatization of them is also described to diversify bioactive compounds.
  • Trifluoromethanesulfonic Acid as Acylation Catalyst: Special Feature for C- and/or O-Acylation Reactions
    Zetryana Puteri Tachrim, Lei Wang, Yuta Murai, Takuma Yoshida, Natsumi Kurokawa, Fumina Ohashi, Yasuyuki Hashidoko, Makoto Hashimoto
    CATALYSTS, 7, 2, MDPI AG, Feb. 2017, [Peer-reviewed]
    English, Trifluoromethanesulfonic acid (TfOH) is one of the superior catalysts for acylation. The catalytic activity of TfOH in C- and/or O-acylation has broadened the use of various substrates under mild and neat or forced conditions. In this review, the salient catalytic features of TfOH are summarized, and the unique controllability of its catalytic activity in the tendency of C-acylation and/or O-acylation is discussed.
  • Synthesis of Nontoxic Fluorous Sphingolipids as Molecular Probes of Exogenous Metabolic Studies for Rapid Enrichment by Fluorous Solid Phase Extraction
    Shota Saito, Yuta Murai, Seigo Usuki, Masafumi Yoshida, Mostafa A. S. Hammam, Susumu Mitsutake, Kohei Yuyama, Yasuyuki Igarashi, Kenji Monde
    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, 6, 1045, 1051, WILEY-V C H VERLAG GMBH, Feb. 2017, [Peer-reviewed], [Corresponding author]
    English, Scientific journal, Fluorous solid-phase extraction (FSPE) is a useful technique for efficient selective enrichment of fluorous compounds from nonfluorous molecules. Sphingolipids and their metabolites, which are ubiquitous building blocks of eukaryotic and prokaryotic cell membranes, play crucial roles, for example, as signaling molecules. However, details of the functions and metabolic mechanisms of exogenous sphingolipids have remained unknown compared with those of their endogenous analogs. To better understand these unknown roles, chemical probes with appropriate biological and physicochemical properties are needed. In this study, we designed and synthesized new fluorous sphingolipids to reveal these roles. Furthermore, we confirmed that they could be efficiently and rapidly separated from normal sphingolipids by FSPE, and that they hardly showed any cytotoxic activity, similarly to normal sphingolipids at the same dose. We also showed that these fluorinated ceramides could act as metabolic substrates for sphingomyelin synthase 2 (SMS2). This demonstrates their potential for further biological studies.
  • 化学プローブは求愛タンパク質の心をどう射留めるのか？-生命現象解明・創薬に小分子の視点から　　　　　　　　　　　　　　　
    門出 健次, 村井 勇太
    化学, 72, 10, 70, 71, 2017, [Invited]
    Japanese
  • Corrigendum: Indole-3-Acetic Acid Produced by Burkholderia heleia Acts as a Phenylacetic Acid Antagonist to Disrupt Tropolone Biosynthesis in Burkholderia plantarii.
    Mengcen Wang, Seiji Tachibana, Yuta Murai, Li Li, Sharon Yu Ling Lau, Mengchao Cao, Guonian Zhu, Makoto Hashimoto, Yasuyuki Hashidoko
    Scientific reports, 6, 26217, 26217, 20 May 2016, [Peer-reviewed], [International Magazine]
    English
  • Stereochemical Study of Sphingosine by Vibrational Circular Dichroism.
    Atsufumi Nakahashi, Ananda Kumar C Siddegowda, Mostafa A S Hammam, Siddabasave Gowda B Gowda, Yuta Murai, Kenji Monde
    Organic letters, 18, 10, 2327, 30, 20 May 2016, [Peer-reviewed], [International Magazine]
    English, Vibrational circular dichroism (VCD) was first applied to the stereochemical analysis of sphingosine. VCD patterns derived from the C═C stretch as well as other mid-infrared (IR) regions were practical markers to discriminate all the stereoisomers of intact sphingosine. Glutaraldehyde was found as an excellent derivatizing reagent for sphingosine which improves its solubility in VCD-friendly nonpolar solvents such as chloroform and enhances the VCD intensities by forming a rigid cyclized structure.
  • Efficient Synthesis of Photoreactive 2-Propoxyaniline Derivatives as Artificial Sweeteners
    Yuta Murai, Takuma Yoshida, Lei Wang, Katsuyoshi Masuda, Yasuyuki Hashidoko, Kenji Monde, Yasumaru Hatanaka, Makoto Hashimoto
    SYNLETT, 27, 6, 946, 950, GEORG THIEME VERLAG KG, Apr. 2016, [Peer-reviewed], [Lead author]
    English, Scientific journal, 5-Nitro-2-propoxyaniline is one of the strongest artificial sweeteners. However, little is known about the detailed relationship of the structure and biological activity between 5-nitro-2-propoxyaniline and its sweet receptor. Photoaffinity labeling is a useful method for revealing interactions of a small bioactive compound with molecules. Therefore, we synthesized photoreactive 2-propoxyaniline derivatives as useful tools for revealing the interactions by photoaffinity labeling.
  • Indole-3-Acetic Acid Produced by Burkholderia heleia Acts as a Phenylacetic Acid Antagonist to Disrupt Tropolone Biosynthesis in Burkholderia plantarii.
    Mengcen Wang, Seiji Tachibana, Yuta Murai, Li Li, Sharon Yu Ling Lau, Mengchao Cao, Guonian Zhu, Makoto Hashimoto, Yasuyuki Hashidoko
    Scientific reports, 6, 22596, 22596, 03 Mar. 2016, [Peer-reviewed], [International Magazine]
    English, Burkholderia heleia PAK1-2 is a potent biocontrol agent isolated from rice rhizosphere, as it prevents bacterial rice seedling blight disease caused by Burkholderia plantarii. Here, we isolated a non-antibacterial metabolite from the culture fluid of B. heleia PAK1-2 that was able to suppress B. plantarii virulence and subsequently identified as indole-3-acetic acid (IAA). IAA suppressed the production of tropolone in B. plantarii in a dose-dependent manner without any antibacterial and quorum quenching activity, suggesting that IAA inhibited steps of tropolone biosynthesis. Consistent with this, supplementing cultures of B. plantarii with either L-[ring-(2)H5]phenylalanine or [ring-(2)H2~5]phenylacetic acid revealed that phenylacetic acid (PAA), which is the dominant metabolite during the early growth stage, is a direct precursor of tropolone. Exposure of B. plantarii to IAA suppressed production of both PAA and tropolone. These data particularly showed that IAA produced by B. heleia PAK1-2 disrupts tropolone production during bioconversion of PAA to tropolone via the ring-rearrangement on the phenyl group of the precursor to attenuate the virulence of B. plantarii. B. heleia PAK1-2 is thus likely a microbial community coordinating bacterium in rhizosphere ecosystems, which never eliminates phytopathogens but only represses production of phytotoxins or bacteriocidal substances.
  • Highly efficient preparation of sphingoid bases from glucosylceramides by chemoenzymatic method.
    Siddabasave Gowda B Gowda, Seigo Usuki, Mostafa A S Hammam, Yuta Murai, Yasuyuki Igarashi, Kenji Monde
    Journal of lipid research, 57, 2, 325, 31, Feb. 2016, [Peer-reviewed], [International Magazine]
    English, Sphingoid base derivatives have attracted increasing attention as promising chemotherapeutic candidates against lifestyle diseases such as diabetes and cancer. Natural sphingoid bases can be a potential resource instead of those derived by time-consuming total organic synthesis. In particular, glucosylceramides (GlcCers) in food plants are enriched sources of sphingoid bases, differing from those of animals. Several chemical methodologies to transform GlcCers to sphingoid bases have already investigated; however, these conventional methods using acid or alkaline hydrolysis are not efficient due to poor reaction yield, producing complex by-products and resulting in separation problems. In this study, an extremely efficient and practical chemoenzymatic transformation method has been developed using microwave-enhanced butanolysis of GlcCers and a large amount of readily available almond β-glucosidase for its deglycosylation reaction of lysoGlcCers. The method is superior to conventional acid/base hydrolysis methods in its rapidity and its reaction cleanness (no isomerization, no rearrangement) with excellent overall yield.
  • Synthesis of Diazirine-Based Photoreactive Saccharin Derivatives for the Photoaffinity Labeling of Gustatory Receptors
    Lei Wang, Takuma Yoshida, Yasuyuki Muto, Yuta Murai, Zetryana Puteri Tachrim, Akiko Ishida, Shiori Nakagawa, Yasuko Sakihama, Yasuyuki Hashidoko, Katsuyoshi Masuda, Yasumaru Hatanaka, Makoto Hashimoto
    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, 14, 3129, 3134, WILEY-V C H VERLAG GMBH, May 2015, [Peer-reviewed]
    English, Scientific journal, Saccharin is one of the most common artificial sweeteners that has a bitter taste at high concentrations. Currently, there are no detailed functional analyses of these gustatory receptors. Therefore, we designed and synthesized photoreactive saccharin derivatives that contain a (trifluoromethyl) diazirinyl moiety at the 5- or 6-position for use as functional analysis tools for photoaffinity labeling.
  • Alternative One-Pot Synthesis of (Trifluoromethyl)phenyldiazirines from Tosyloxime Derivatives: Application for New Synthesis of Optically Pure Diazirinylphenylalanines for Photoaffinity Labeling
    Lei Wang, Yuta Murai, Takuma Yoshida, Akiko Ishida, Katsuyoshi Masuda, Yasuko Sakihama, Yasuyuki Hashidoko, Yasumaru Hatanaka, Makoto Hashimoto
    ORGANIC LETTERS, 17, 3, 616, 619, AMER CHEMICAL SOC, Feb. 2015, [Peer-reviewed]
    English, Scientific journal, Alternative one-pot synthesis of 3-(trifluoromethyl)-3-phenyldiazirine derivatives from corresponding tosyloximes is developed. The deprotonation of intermediate diaziridine by NH2- is a new approach for construction of diazirine. Moreover, a novel synthesis of optically pure (trifluoromethyl)diazirinylphenylalanine derivatives was attempted involving these methods.
  • SYNTHESIS OF PHOTOREACTIVE DIAZIRINYL SALICIN DERIVATIVE TO ELUCIDATE FUNCTIONAL ANALYSIS OF THE BITTER TASTE RECEPTOR
    Munenori Sakurai, Takuma Yoshida, Lei Wang, Yuta Murai, Katsuyoshi Masuda, Yasuko Sakihama, Yasuyuki Hashidoko, Yasumaru Hatanaka, Makoto Hashimoto
    HETEROCYCLES, 90, 1, 698, 705, PERGAMON-ELSEVIER SCIENCE LTD, Jan. 2015, [Peer-reviewed]
    English, Scientific journal, Salicin (salicyl alcohol glucoside) is a substance well known for its bitter taste. A photoreactive diazirinyl derivative of salicin will be utilized for the functional analysis of interactions between the bitter taste receptor and salicin. Glucosides of salicyl derivatives are more difficult than phenol derivatives that are unsubstituted at the ortho-position. A diazirinyl salicin derivative was synthesized at moderate yields by glucosidation of 2,3,4,6-tetra-O-acetyl-alpha-D-glucopyranosyl bromide and 2-hydroxy-4-[3-(trifluoromethyl)-3H-diazirin-3-yl]benzaldehyde in the presence of a phase-transfer catalyst, nBuEt(3)NBr, followed by reduction and deprotection.
  • Hydrogen/deuterium exchange of cross-linkable alpha-amino acid derivatives in deuterated triflic acid
    Lei Wang, Yuta Murai, Takuma Yoshida, Masashi Okamoto, Katsuyoshi Masuda, Yasuko Sakihama, Yasuyuki Hashidoko, Yasumaru Hatanaka, Makoto Hashimoto
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 78, 7, 1129, 1134, TAYLOR & FRANCIS LTD, Jul. 2014, [Peer-reviewed]
    English, Scientific journal, In this paper we report here a hydrogen/deuterium exchange (H/D exchange) of cross-linkable alpha-amino acid derivatives with deuterated trifluoromethanesulfonic acid (TfOD). H/D exchange with TfOD was easily applied to o-catechol containing phenylalanine (DOPA) within an hour. A partial H/D exchange was observed for trifluoromethyldiazirinyl (TFMD) phenylalanine derivatives. N-Acetyl-protected natural aromatic alpha-amino acids (Tyr and Trp) were more effective in H/D exchange than unprotected ones. The N-acetylated TFMD phenylalanine derivative afforded slightly higher H/D exchange than unprotected derivatives. An effective post-deuteration method for cross-linkable alpha-amino acid derivatives will be useful for the analysis of biological functions of bioactive peptides and proteins by mass spectrometry.
  • Utilization of Acidic alpha-Amino Acids as Acyl Donors: An Effective Stereo-Controllable Synthesis of Aryl-Keto alpha-Amino Acids and Their Derivatives
    Lei Wang, Yuta Murai, Takuma Yoshida, Masashi Okamoto, Zetryana Puteri Tachrim, Yasuyuki Hashidoko, Makoto Hashimoto
    MOLECULES, 19, 5, 6349, 6367, MDPI AG, May 2014, [Peer-reviewed]
    English, Aryl-keto-containing alpha-amino acids are of great importance in organic chemistry and biochemistry. They are valuable intermediates for the construction of hydroxyl alpha-amino acids, nonproteinogenic alpha-amino acids, as well as other biofunctional components. Friedel-Crafts acylation is an effective method to prepare aryl-keto derivatives. In this review, we summarize the preparation of aryl-keto containing alpha-amino acids by Friedel-Crafts acylation using acidic alpha-amino acids as acyl-donors and Lewis acids or Bronsted acids as catalysts.
  • Synthesis of Photoreactive Aromatic alpha-Amino Acids and Effective Hydrogen-Deuterium Exchange for Aromatic alpha-Amino Acids
    Makoto Hashimoto, Yuta Murai
    JOURNAL OF SYNTHETIC ORGANIC CHEMISTRY JAPAN, 72, 4, 360, 369, SOC SYNTHETIC ORGANIC CHEM JPN, Apr. 2014, [Peer-reviewed]
    Japanese, Scientific journal, Photoaffinity labeling is one of the favorite methods for chemical biology. The first step in this method is the construction of photophores and their modification to the associated high affinity target ligand. alpha-Amino acids have biological activities themselves and are fundamental component of peptides and protein. The photoreactive aromatic alpha-amino acids are useful for investigation of biological phenomenon. Although synthesis of photoreactive phenylalanine analogues has already been reported, there have been few reports of the synthesis of photoreactive tryptophan and side-chain elongated phenylalanine. We report here the effective photoreactive tryptophan and side-chain elongated phenylalanine derivatives. Furthermore, we report the mild and controllable hydrogen-deuterium exchange for aromatic hydrogen with trifluoromethanesulfonic acid-d during the course of the synthesis of side-chain elongated phenylalanine. These hydrogen-deuterium exchange properties for these aromatic alpha-amino acids are identical to those of the peptides. With this method the exchange proceeds significantly faster than previously described methods. Detail analysis of the exchange revealed that the method was controllable by temperature-, time-, and dose- dependent manner.
  • SYNTHESIS OF METHOXY-SUBSTITUTED DIAZIRINYL PHENYLALANINE -A NOVEL PHOTOREACTIVE ASPARTAME DERIVATIVE FOR FUNCTIONAL ANALYSIS OF SWEET RECEPTORS
    Sakurai, Munenori, Masuda, Katsuyoshi, Wang, Lei, Murai, Yuta, Sakihama, Yasuko, Hashidoko, Yasuyuki, Hatanaka, Yasumaru, Hashimoto, Makoto
    HETEROCYCLES, 88, 1, 629, 637, PERGAMON-ELSEVIER SCIENCE LTD, Jan. 2014, [Peer-reviewed]
    English, Scientific journal, Photoreactive phenylalanine derivatives are well known as functional analysis reagents for target biomolecules. The photophores are commonly introduced at 4-position on benzene. Aspartame, which consists of dipeptide L-Asp-L-Phe-OMe, is one of the most utilized artificial sweeteners, and substitution effects on its benzene ring have been reported. Substitution at the 4-position, however, does not maintain its sweetness properties. Trifluoromethyldiazirine, which is one of the most reliable photophores, was introduced to a different site on phenylalanine and the new photoreactive phenylalanine was converted to aspartame derivatives. The new aspartame derivative had slightly higher sweetness potency than sucrose standard solution.
  • SIMPLE AND STEREOCONTROLLED PREPARATION OF BENZOYLATED PHENYLALANINE USING FRIEDEL - CRAFTS REACTION IN TRIFLUOROMETHANESULFONIC ACID FOR PHOTOAFFINITY LABELING
    Yuta Murai, Lei Wang, Yasuyuki Muto, Yasuko Sakihama, Yasuyuki Hashidoko, Yasumaru Hatanaka, Makoto Hashimoto
    HETEROCYCLES, 87, 10, 2119, 2126, PERGAMON-ELSEVIER SCIENCE LTD, Oct. 2013, [Peer-reviewed], [Lead author]
    English, Scientific journal, Simple and stereocontrolled preparation of benzoylated phenylalanine derivatives from optically pure phenylalanine using Friedel-Crafts reaction in trifluoromethanesulfonic acid (TfOH) is reported; these derivatives are useful for photoaffinity labeling. Protected or unprotected phenylalanine derivatives were converted to benzoyl derivatives in TfOH at room temperature in a short time without loss of optical purity. The reaction condition was applied to synthesize novel photoreactive phenylalanine derivative, which has two photophores (benzophenone and diazirine). The detail analysis of photo-irradiation for two different photophores contained phenylalanine derivative was also investigated.
  • Distinct Metabolites for Photoreactive L-Phenylalanine Derivatives in Klebsiella sp CK6 Isolated from Rhizosphere of a Wild Dipterocarp Sapling
    Lei Wang, Wataru Hisano, Yuta Murai, Munenori Sakurai, Yasuyuki Muto, Haruka Ikemoto, Masashi Okamoto, Takashi Murotani, Reika Isoda, Dongyeop Kim, Yasuko Sakihama, Irnayuli R. Sitepu, Yasuyuki Hashidoko, Yasumaru Hatanaka, Makoto Hashimoto
    MOLECULES, 18, 7, 8393, 8401, MDPI AG, Jul. 2013, [Peer-reviewed]
    English, Scientific journal, Photoaffinity labeling is a reliable analytical method for biological functional analysis. Three major photophores-aryl azide, benzophenone and trifluoromethyldiazirine-are utilized in analysis. Photophore-bearing L-phenylalanine derivatives, which are used for biological functional analysis, were inoculated into a Klebsiella sp. isolated from the rhizosphere of a wild dipterocarp sapling in Central Kalimantan, Indonesia, under nitrogen-limiting conditions. The proportions of metabolites were quite distinct for each photophore. These results indicated that photophores affected substrate recognition in rhizobacterial metabolic pathways, and differential photoaffinity labeling could be achieved using different photophore-containing L-phenylalanine derivatives.
  • Synthesis of photoreactive 2-phenethylamine derivatives-synthesis of adenosine derivatives enabling functional analysis of adenosine receptors by photoaffinity labeling
    Yuta Murai, Katsuyoshi Masuda, Yui Ogasawara, Lei Wang, Yasuyuki Hashidoko, Yasumaru Hatanaka, So Iwata, Takuya Kobayashi, Makoto Hashimoto
    European Journal of Organic Chemistry, 12, 2428, 2433, Apr. 2013, [Peer-reviewed], [Lead author]
    English, Scientific journal, 2-Phenylethylamine is well known as a substructure of many biologically active compounds, and the synthesis of its photoreactive derivatives to allow the analysis of biological functions is reported. This allowed us to synthesise ligands for adenosine receptors, which have many functional roles in biology and have been extensively studied for their many roles in maintaining homeostasis. Adenosine is one of the most common biochemical compounds, but photoaffinity labeling has not yet been used to study adenosine receptors. Synthetic methods for producing photoreactive adenosine derivatives that can be used with adenosine receptors were established for the photophores phenyl azide and benzophenone. The effect of the introduction of the photoreactive components was determined using an adenosine receptor assay. © 2013 WILEY-VCH Verlag GmbH &
    Co. KGaA, Weinheim.
  • Rapid and controllable hydrogen/deuterium exchange on aromatic rings of α-amino acids and peptides
    Yuta Murai, Lei Wang, Katsuyoshi Masuda, Yasuko Sakihama, Yasuyuki Hashidoko, Yasumaru Hatanaka, Makoto Hashimoto
    European Journal of Organic Chemistry, 2013, 23, 5111, 5116, 2013, [Peer-reviewed], [Lead author]
    English, Scientific journal, Novel hydrogen/deuterium exchange for aromatic α-amino acids and their corresponding peptides were performed through the use of deuterated trifluoromethanesulfonic acid (TfOD). Detailed analysis of the exchange revealed that equal hydrogen/deuterium exchange was observed for phenylalanine, and specific exchange at the ortho-positions of phenol for tyrosine was also detected. The stereochemistry of the aromatic α-amino acids was retained under the exchange conditions. The hydrogen/deuterium exchange properties for these aromatic α-amino acids are identical for peptides that contain several aromatic α-amino acids. The exchange proceeded significantly faster than previous methods. Detailed analysis of the exchange revealed that the method could be controlled by temperature, time, and the amount of reagent. Deuterated trifluoromethanesulfonic acid promotes rapid and controllable hydrogen/deuterium exchange on aromatic rings of α-amino acids and peptides at room temperature and below. The deuterium incorporation depends on the amount of reagent, the temperature, and the time-scale of the reaction. Copyright © 2013 WILEY-VCH Verlag GmbH &
    Co. KGaA, Weinheim.
  • QUANTITATIVE ANALYSIS OF Cu(I) CONCENTRATION IN CLICK CHEMISTRY -BIOTINYLATION AT SIDE CHAIN OF PROPARGYLGLYCINE USING CLICK CHEMISTRY UNDER HEATING CONDITIONS-
    Yui Ogasawara, Yuta Murai, Yasuko Sakihama, Yasuyuki Hashidoko, Makoto Hashimoto
    HETEROCYCLES, 86, 1, 735, 743, PERGAMON-ELSEVIER SCIENCE LTD, Dec. 2012, [Peer-reviewed]
    English, Scientific journal, The click reaction is one of the latest techniques for the chemical modification of bioactive compounds. Chemical modifications of alpha-amino acid side chains are gaining significance as useful and important tools for biochemical research. Biotinylation at side chain of propargylglycine using click reaction was examined. The detail quantitative analysis of Cu(I) concentration are performed to proceed the click reaction effectively.
  • Quantitative determination of click reaction in the presence of glycine derivatives and in dilute solution
    Yui Ogasawara, Yuta Murai, Yasuko Sakihama, Yasuyuki Hashidoko, Makoto Hashimoto
    International Journal of Organic Chemistry, 2, 3, 302, 304, Scientific Research Publishing, Inc., Nov. 2012, [Peer-reviewed]
    English, Scientific journal
  • Effective Friedel-Crafts Acylation of Biotin Acid Chloride in Trifluoromethanesulfonic Acid
    Yasuyuki Muto, Yuta Murai, Yasuko Sakihama, Yasuyuki Hashidoko, Makoto Hashimoto
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 76, 11, 2162, 2164, TAYLOR & FRANCIS LTD, Nov. 2012, [Peer-reviewed]
    English, Scientific journal, Biotin is one of the most useful tags in (bio)analytical science due to its specific interaction with avidin, but is not easy to convert because of its low solubility in most solvents. Friedel-Crafts acylation of biotin acid chloride in triflic acid was examined, and the synthesized derivatives had stronger affinity to avidin than biotin in a binding assay using 2-(4'-hydroxyphenylazo)benzoic acid.
  • Comprehensive Synthesis of Photoreactive (3-Trifluoromethyl)diazirinyl Indole Derivatives from 5- and 6-Trifluoroacetylindoles for Photoaffinity Labeling
    Yuta Murai, Katsuyoshi Masuda, Yasuko Sakihama, Yasuyuki Hashidoko, Yasumaru Hatanaka, Makoto Hashimoto
    JOURNAL OF ORGANIC CHEMISTRY, 77, 19, 8581, 8587, AMER CHEMICAL SOC, Oct. 2012, [Peer-reviewed], [Lead author]
    English, Scientific journal, 5- and 6-trifluoromethyldiazirinyl indoles were synthesized from corresponding bromoindole derivatives for the first time. They acted as mother skeletons for the comprehensive synthesis of various bioactive indole metabolites. These can be used in biological functional analysis as diazirine-based photoaffinity labels.
  • CHEMO-ENZYMATIC SYNTHESIS OF 1 '-PHOTOREACTIVE SUCROSE DERIVATIVES VIA ETHER LINKAGE
    Yuka Tsunekawa, Katsuyoshi Masuda, Miho Muto, Yasuyuki Muto, Yuta Murai, Yasuyuki Hashidoko, Yoshitake Orikasa, Yuji Oda, Yasumaru Hatanaka, Makoto Hashimoto
    HETEROCYCLES, 84, 1, 283, 290, PERGAMON-ELSEVIER SCIENCE LTD, Jan. 2012, [Peer-reviewed]
    English, Scientific journal, As the 1'-hydroxyl group of sucrose is well known to be less reactive than other primary alcohols, there are no reports on the substitution of a phenoxy group at this position. Chemo-enzymatic synthesis of photoreactive 1'-phenoxy-substituted sucrose was examined to elucidate the functional analysis of sweet receptors.
  • Novel Synthesis of Optically Active Bishomotyrosine Derivatives Using the Friedel-Crafts Reaction in Triflic Acid
    Yuta Murai, Yasuyuki Hashidoko, Makoto Hashimoto
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 75, 2, 352, 354, TAYLOR & FRANCIS LTD, Feb. 2011, [Peer-reviewed], [Lead author]
    English, Scientific journal, We report here a novel synthesis of optically active bishomotyrosine. The bishomotyrosine skeleton was constructed by using a Friedel-Crafts reaction between phenol and optically active N-Tfa-Glu(Cl)-OMe in triflic acid under the mild condition. Reduction and subsequent deprotection then afforded bishomotyrosine derivatives without any loss of optical purity.
  • Comparisons of O-acylation and Friedel-Crafts acylation of phenols and acyl chlorides and Fries rearrangement of phenyl esters in trifluoromethanesulfonic acid: effective synthesis of optically active homotyrosines
    Ryo Murashige, Yuka Hayashi, Syo Ohmori, Ayuko Torii, Yoko Aizu, Yasuyuki Muto, Yuta Murai, Yuji Oda, Makoto Hashimoto
    TETRAHEDRON, 67, 3, 641, 649, PERGAMON-ELSEVIER SCIENCE LTD, Jan. 2011, [Peer-reviewed]
    English, Scientific journal, Reactions involving phenol derivatives and acyl chlorides have to be controlled for competitive O-acylations and C-acylations (Friedel Crafts acylations and Fries rearrangements) in acidic condition. The extent for these reactions in trifluoromethanesulfonic acid (TfOH), which is used as catalyst and solvent, is examined. Although diluted TfOH was needed for effective O-acylation, concentrated TfOH was required for effective C-acylations in mild condition. These results have been applied to the novel synthesis of homotyrosine derivatives. Both Fries rearrangement of N-TFA-Asp(OBn)-OMe and Friedel-Crafts acylation of phenol with N-TFA Asp(Cl)-OMe in TfOH afforded the homotyrosine skeleton, followed by reduction and deprotection afforded homotyrosines maintaining stereochemistry of Asp as an optically pure form. (C) 2010 Elsevier Ltd. All rights reserved.
  • SIMPLE DEUTERIUM INTRODUCTION AT alpha-POSITION OF CARBONYL IN DIAZIRINYL DERIVATIVES FOR PHOTOAFFINITY LABELING
    Yuta Murai, Miho Takahashi, Yasuyuki Muto, Yasumaru Hatanaka, Makoto Hashimoto
    HETEROCYCLES, 82, 1, 909, 915, PERGAMON-ELSEVIER SCIENCE LTD, Dec. 2010, [Peer-reviewed], [Lead author]
    English, Scientific journal, Post-functional deuterium incorporation into diazirinyl acetophenone derivatives is reported. Treatment of the compounds with sodium hydroxide in CH3OD at rt for 10 min achieved deuterium incorporation at alpha-position of the carbonyl group without decomposition of diazirinyl ring. Further deuterium can introduce by reduction of benzyl carbonyl with triethylsilane-d-TFA. Straightforward deuterium introduction into diazirinyl derivatives may contribute to the functional analysis of low molecular compounds with diazirine-based photoaffinity labeling.
  • Effective Synthesis of Optically Active Trifluoromethyldiazirinyl Homophenylalanine and Aroylalanine Derivatives with the Friedel-Crafts Reaction in Triflic Acid
    Ryo Murashige, Yuta Murai, Yasumaru Hatanaka, Makoto Hashimoto
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 73, 6, 1377, 1380, TAYLOR & FRANCIS LTD, Jun. 2009, [Peer-reviewed]
    English, Scientific journal, The Friedel-Crafts reaction with 3-(3-methoxy-phenyl)-3-(trifluoromethyl)-3H-diazirine and optically active N-TFA-Asp(Cl)-OMe in triflic acid afforded homophenylalanine derivatives without any loss of the optical purity.
  • EFFECTIVE SYNTHESIS OF OPTICALLY ACTIVE 3-PHENYL-3-(3-TRIFLUOROMETHYL) DIAZIRINYL BISHOMOPHENYLALANINE DERIVATIVES
    Yuta Murai, Yasumaru Hatanaka, Yulichi Kanaoka, Makoto Hashimoto
    HETEROCYCLES, 79, 359, 364, PERGAMON-ELSEVIER SCIENCE LTD, Apr. 2009, [Peer-reviewed], [Lead author]
    English, Scientific journal, Effective incorporation of phenyldiazirine moiety on the acyl residue of (L)- and (D)- glutamic acid by Friedel-Crafts reactions with triflic acid developed simple preparation of bishomophenylalanine (bhPhe) for aromatics, which added a versatile and a reliable access to photoreactive peptide probes.

Other Activities and Achievements

Research Themes

  • 皮下深部の非浸潤癌診断を目指した短波赤外蛍光色素イメージング技術の開発
    科学研究費助成事業
    Apr. 2024 - Mar. 2027
    村井 勇太
    日本学術振興会, 基盤研究(C), 北海道大学, 24K08626
  • スフィンゴミエリン合成酵素２阻害剤による腫瘍免疫亢進を介した新規抗癌治療の開発
    科学研究費助成事業
    01 Apr. 2022 - 31 Mar. 2025
    岡崎 俊朗, 村井 勇太, 谷口 真, 門出 健次
    日本学術振興会, 基盤研究(B), 石川県立大学, 22H02926
  • スフィンゴ脂質病の新規治療法を指向した光キャプチャーによるSMS2阻害様式の解明
    科学研究費助成事業
    01 Apr. 2021 - 31 Mar. 2024
    村井 勇太
    本年度は独自のスフィンゴミエリン合成酵素2 (SMS2)選択的な阻害剤を搭載したノシルジアジリン型光アフィニティーラベル (NsPAL)プローブの作成を行なった。当初の計画通り、阻害剤のスフィンゴシン尾部末端にNsジアジリンを導入したものを構築し、NsPALプローブの阻害活性を確認したところ、SMS2選択性およびIC50値0.2uMを保持していることが確認できた。続いてこのNsPALプローブの光ラベル効率を検討するため、光照射によるジアジリン基の光分解を検討した。ジアジリン基の一般的な光分解波長は365nmであるが、本プローブでは分解効率が悪かった。そこで光波長を325-385nmのレンジで照射したところ、0℃、10分で完全に光分解を達成することに成功した。さらにNsPALプローブによる標的分子の光ラベル後は、Ns基特有の芳香族求核置換反応 (SNAr)を利用し、標的分子に検出タグ導入を考えていることから、SNAr条件についても検討を行なった。初め、検出タグとしてBodipy-SHを構築したが、脂溶性が高く生体分子への非特異的吸着が見られた。そこで親水性のPEG鎖をBodipyとチオール基の間に挿入することで、非特異的吸着を可能な限り抑制し、水溶性を保持したBodipy-PEG-SHを作成した。またSNAr反応は通常、有機溶媒中、加熱、塩基条件が必要とされるが、PAL法は水中で実施されるためSNArの効率的な条件を検討する必要があった。これまでの種々条件検討の結果、pH 9.0、 炭酸緩衝液中、70℃で反応が進む知見を得ていたが、副生成物による低収率がボトルネックであった。今回はさらに条件検討を行い、室温、超音波中で実施したところ効率良くSNArが進行することを見出すことにも成功した。
    日本学術振興会, 基盤研究(C), 北海道大学, 21K05303
  • Development of novel stereochemical analytical technique of biomolecules by the VCD exciton chirality method
    Grants-in-Aid for Scientific Research
    01 Apr. 2019 - 31 Mar. 2023
    門出 健次, 谷口 透, 村井 勇太
    昨年に引き続き、アルキン、アジド、ニトリル等のIR官能基のVCD励起子キラリティー法への応用可能性を検証するために、各種IR官能基を有する化合物を合成し、その実測VCDを検証した。生体関連中分子に対して、VCD励起子キラリティー法を適用させるため、中分子として、アシルセラミドを選び、分子内の二つのカルボニル基に対してのVCD励起子キラリティー法の適用を考えた。アシルセラミドは、人間の皮膚のバリア機能を担う巨大スフィンゴ脂質分子である。近年、アトピー性皮膚炎の原因がアシルセラミド合成酵素の欠損によるものであることが発見されている。創薬的見地からも、この巨大アシルセラミド分子の全合成研究を実施する。本分子には二つの不斉炭素があるが、その絶対配置決定（例えば天然体）は、通常の方法では極めて困難である。まず、超長鎖脂肪酸を有するセラミドの二級水酸基にアシル基を導入することにより、VCD励起子キラリティー法の適用が可能となると考えた。アシルセラミドは、細長い分子であるが、皮膚上で特殊な構造をとると考えられている。化学合成による純粋なサンプル供給を目指し、スフィンゴ塩基部分、および、長鎖部位の合成に成功し、全合成にむけての部分合成を実施した。特に、長鎖脂肪酸の合成に注力した。オメガ９位に二重結合を有する超長鎖脂肪酸は、これまでにほとんど合成例がない。超長鎖炭化水素の反応性の特性を溶媒により制御する方法を見出し、Wittig反応を基本としたカップリング反応により、C34:1の脂肪酸の合成に成功した。
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 19H02836
  • Design of ligand-tag exchangeable new photoaffinity probe utilizing nosyl chemistry
    Grants-in-Aid for Scientific Research
    01 Apr. 2018 - 31 Mar. 2021
    Murai Yuta
    In existing photoaffinity labeling methods, there are some problems such as decreasing the original affinity of a ligand due to their bulkiness of the photoaffinity probe and complicated work within an analysis time. Therefore, innovative improvement of the photoaffinity labeling methodology as a simpler analysis tool for all researchers is required. In this study, I developed a novel photoaffinity probe possessing multi-tag exchangeable ability utilizing the characteristics of the nosyl chemistry. The developed photoaffinity probe improved the photolabeling efficiency to the target molecule, and can be exchanged for detection groups (fluorescent group or ion sensitizer) of the ligand by nucleophilic aromatic substituted reaction (SNAr). These advantages was able to overcome the previous problems and may contribute a large number of chamical biology research field.
    Japan Society for the Promotion of Science, Grant-in-Aid for Early-Career Scientists, Hokkaido University, 18K14350
  • 皮膚バリア強化に対応した植物性ハイブリッド脂質の大量供給プロセスの開発研究
    産学が連携した研究開発成果の展開 研究成果展開事業 研究成果最適展開支援プログラム(A-STEP) トライアウト トライアウト
    2020 - 2021
    村井 勇太
    我々は、乳児や高齢者の繊細な皮膚にも安全で日常的に塗布できる「皮膚バリア増強剤」を目指し、皮膚バリアに必須なヒト型アシルセラミドと、皮膚増強及びかゆみ防止効果を持つ植物性脂質の「ハイブリッド脂質」を創製してきた。しかし、実用化には、1高保湿性、2安全、3大量合成、4簡易工程(コストダウン)、5高収率等の課題がある。一方、我々は既に、1)アシルセラミド合成技術と2)加水分解法による植物(タモギタケ由来、他)長鎖塩基獲得技術(特許出願済)を確立しており、これら技術を融合させ、上記課題解決を行う。これは、皮膚バリア増強をキーワードとする化粧品、塗り薬の基材、人工皮膚モデル等と多岐用途に貢献する。
    科学技術振興機構, 北海道大学, Principal investigator
  • Study for molecules initiated lipid related disease biomarkers
    Grants-in-Aid for Scientific Research
    30 Jun. 2017 - 31 Mar. 2020
    Monde Kenji
    L-serine, the head part of a sphingosine, is incorporated by serine palmitoyl transferase (SPT）, coupled with a palmitoyl CoA in the first stage of its biosynthesis and converted into ceramides. Recently, it has been suggested that not only L-serine but also other amino acids may be incorporated into this biosynthetic system, and its association with lipid-related diseases has been trend. We have been succeeded in synthesizing sphingosines having phenylalanine, alanine, tryptophan, leucine, cysteine, and threonine in its head part for the purpose of providing authentic standard samples in a mass spectrometric analysis. We also constructed a unique ceramide library by binding some of these to fatty acids. It was found that some of them showed inhibitory activity of sphingomyelin synthase.
    Japan Society for the Promotion of Science, Grant-in-Aid for Challenging Research (Exploratory), Hokkaido University, 17K19188
  • Elucidation of the biosynthesis mechanism of acylceramides including ultra-long-chain fatty acid as a skin barrier function
    Grants-in-Aid for Scientific Research
    01 Apr. 2015 - 31 Mar. 2018
    MURAI Yuta
    Acylceramides in mammalian epidermal keratinocytes, including unique ultra-long-chain (C30-C36) fatty acids, have been known as a significant component of a skin barrier. Although acylceramides are present in only about 5-8% of the total lipid in a skin barrier, its deficiency causes severe skin diseases such as atopic dermatitis, ichthyosis, dry skin and psoriasis. In acylceramides, the most abundant molecular species includes the unsaturated ultra-long-chain fatty acid (C34:1). However, the details of its physical property and the potential therapeutic use have not completely elucidated due to less report to synthesize acylceramides so far. In this study, an efficient synthsis of acyceramides including unsaturated ultar-long-chain fatty acid (C34:1 and C34:1) in big-scale.
    Japan Society for the Promotion of Science, Grant-in-Aid for Young Scientists (B), Hokkaido University, 15K16552
  • Investigation of horizontal transmission among N2O emission-associated genes and N2O emission suppressing chemical agents
    Grants-in-Aid for Scientific Research
    01 Apr. 2014 - 31 Mar. 2018
    Hashidoko Yasuyuki
    Active N2O emitting microorganisms were searched for, at the soils from reclaimed tropical peatland in Malaysia, Andisol corn farmland in Hokkaido, and palsa mire-degrading boreal peat in Finland Lapland, all of which are known as active N2O emission hotspots. Resulting active N2O emitting bacteria were compared their physiological and biological traits. Burkholderia spp. isolated as a hyper-active N2O emitter from tropical peat soils s were missing nosZ genes, while 4 strains out of 10 active N2O emitting Pseudomonas spp. rather harbored weakly functional nosZ gene. In boreal peatland, particularly degrading palsa bogs, Rhizobium sp. and Serratia sp. mixed colonies had abilities to release N2O from NO2-.
    In investigation of N2O production-repressing chemicals, Paraquat and allylisothiocyanate showed relatively strong N2O-emission inhibitory effect. For further screening, several differentiation-inducing factors toward bacteria were isolated and identified.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, 26252058
  • Development of the novel determination methodology for absolute configuration without theoretical calculation
    Grants-in-Aid for Scientific Research
    01 Apr. 2012 - 31 Mar. 2015
    MONDE Kenji, TANIGUCHI Tohru, MURAI Yuta
    Vibrational circular dichroism (VCD) is a reliable and non-empirical method which can determine absolute configuration. However, ab initio theoretical calculation for its conformational analysis of a target molecule is essential. In this project, a new methodology for determination of absolute configuration without its theoretical calculation has been developed by utilizing a huge bisignate VCD signal caused by their interaction of two IR functional groups such as carbonyl groups in a target molecule.
    This novel methodology named as “VCD exciton chirality method” has been applied to a variety of carbohydrates, steroids, complex natural products, acyclic biological active lipids, and poly lactic acid as a polymer, which shows its high applicability.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 24310151