博士（理学）, 電気通信大学, 2018年09月

Synthesis and anti-tumor activities in human leukemia-derived cells of polyenylpyrroles with a methyl group at the conjugated polyene terminus
Tomoya Higashi; Chihiro Yoshida; Yoshifumi Hachiro; Chihiro Nakata; Azusa Takechi; Takuya Yagi; Kazuya Miyashita; Nobuo Kitada; Rika Obata; Takashi Hirano; Takahiko Hara; Shojiro A. Maki
Bioorganic & Medicinal Chemistry Letters, Elsevier BV, 95巻, 掲載ページ 129471-129471, 出版日 2023年10月
研究論文（学術雑誌）

Identification of compounds that preferentially suppress the growth of T‐cell acute lymphoblastic leukemia‐derived cells
Kazuya Miyashita; Takuya Yagi; Noritaka Kagaya; Azusa Takechi; Chihiro Nakata; Risa Kanda; Hideko Nuriya; Kosuke Tanegashima; Shota Hoyano; Fumiya Seki; Chihiro Yoshida; Yoshifumi Hachiro; Tomoya Higashi; Nobuo Kitada; Takashi Toya; Takeshi Kobayashi; Yuho Najima; Susumu Goyama; Shojiro A. Maki; Toshio Kitamura; Noriko Doki; Kazuo Shin‐ya; Takahiko Hara
Cancer Science, Wiley, 114巻, 10号, 掲載ページ 4032-4040, 出版日 2023年07月31日, Abstract

T‐cell acute lymphoblastic leukemia (T‐ALL) is one of the most frequently occurring cancers in children and is associated with a poor prognosis. Here, we performed large‐scale screening of natural compound libraries to identify potential drugs against T‐ALL. We identified three low‐molecular‐weight compounds (auxarconjugatin‐B, rumbrin, and lavendamycin) that inhibited the proliferation of the T‐ALL cell line CCRF‐CEM, but not that of the B lymphoma cell line Raji in a low concentration range. Among them, auxarconjugatin‐B and rumbrin commonly contained a polyenyl 3‐chloropyrrol in their chemical structure, therefore we chose auxarconjugatin‐B for further analyses. Auxarconjugatin‐B suppressed the in vitro growth of five human T‐ALL cell lines and two T‐ALL patient‐derived cells, but not that of adult T‐cell leukemia patient‐derived cells. Cultured normal T cells were several‐fold resistant to auxarconjugatin‐B. Auxarconjugatin‐B and its synthetic analogue Ra#37 depolarized the mitochondrial membrane potential of CCRF‐CEM cells within 3 h of treatment. These compounds are promising seeds for developing novel anti‐T‐ALL drugs.
研究論文（学術雑誌）

In vivo optical imaging of tumor stromal cells with hypoxia‐inducible factor activity
Hitomi Miyabara; Ryuichiro Hirano; Shigeaki Watanabe; John Clyde Co Soriano; Hitomi Watanabe; Takahiro Kuchimaru; Nobuo Kitada; Tetsuya Kadonosono; Shojiro A. Maki; Gen Kondoh; Shinae Kizaka‐Kondoh
Cancer Science, Wiley, 114巻, 10号, 掲載ページ 3935-3945, 出版日 2023年07月22日, Abstract

Tumors contain various stromal cells, such as immune cells, endothelial cells, and fibroblasts, which contribute to the development of a tumor‐specific microenvironment characterized by hypoxia and inflammation, and are associated with malignant progression. In this study, we investigated the activity of intratumoral hypoxia‐inducible factor (HIF), which functions as a master regulator of the cellular response to hypoxia and inflammation. We constructed the HIF activity‐monitoring reporter gene hypoxia‐response element‐Venus‐Akaluc (HVA) that expresses the green fluorescent protein Venus and modified firefly luciferase Akaluc in a HIF activity‐dependent manner, and created transgenic mice harboring HVA transgene (HVA‐Tg). In HVA‐Tg, HIF‐active cells can be visualized using AkaBLI, an ultra‐sensitive in vivo bioluminescence imaging technology that produces an intense near‐infrared light upon reaction of Akaluc with the D‐luciferin analog AkaLumine‐HCl. By orthotopic transplantation of E0771, a mouse triple negative breast cancer cell line without a reporter gene, into HVA‐Tg, we succeeded in noninvasively monitoring bioluminescence signals from HIF‐active stromal cells as early as 8 days after transplantation. The HIF‐active stromal cells initially clustered locally and then spread throughout the tumors with growth. Immunohistochemistry and flow cytometry analyses revealed that CD11b⁺F4/80⁺ macrophages were the predominant HIF‐active stromal cells in E0771 tumors. These results indicate that HVA‐Tg is a useful tool for spatiotemporal analysis of HIF‐active tumor stromal cells, facilitating investigation of the roles of HIF‐active tumor stromal cells in tumor growth and malignant progression.
研究論文（学術雑誌）

Creation of artificial luciferase 60s from sequential insights and their applications to bioassays
Sung-Bae Kim; Tadaomi Furuta; Nobuo Kitada; Shojiro A. Maki
Sensors, MDPI AG, 23巻, 14号, 掲載ページ 6376-6376, 出版日 2023年07月, 査読付, In this study, a series of new artificial luciferases (ALucs) was created using sequential insights on missing peptide blocks, which were revealed using the alignment of existing ALuc sequences. Through compensating for the missing peptide blocks in the alignment, 10 sibling sequences were artificially fabricated and named from ALuc55 to ALuc68. The phylogenetic analysis showed that the new ALucs formed an independent branch that was genetically isolated from other natural marine luciferases. The new ALucs successfully survived and luminesced with native coelenterazine (nCTZ) and its analogs in living mammalian cells. The results showed that the bioluminescence (BL) intensities of the ALucs were interestingly proportional to the length of the appended peptide blocks. The computational modeling revealed that the appended peptide blocks created a flexible region near the active site, potentially modulating the enzymatic activities. The new ALucs generated various colors with maximally approximately 90 nm redshifted BL spectra in orange upon reaction with the authors’ previously reported 1- and 2-series coelenterazine analogs. The utilities of the new ALucs in bioassays were demonstrated through the construction of single-chain molecular strain probes and protein fragment complementation assay (PCA) probes. The success of this study can guide new insights into how we can engineer and functionalize marine luciferases to expand the toolbox of optical readouts for bioassays and molecular imaging.
研究論文（学術雑誌）, 英語

Coelenterazine indicators for the specific imaging of human and bovine serum albumins
Sung-Bae Kim; Genta Kamiya; Tadaomi Furuta; Nobuo Kitada; Shojiro A
Sensors, MDPI AG, 23巻, 13号, 掲載ページ 6020, 出版日 2023年06月, 査読付, Albumin assays in serum are important for the prognostic assessment of many life-threatening diseases, such as heart failure, liver disease, malnutrition, inflammatory bowel disease, infections, and kidney disease. In this study, synthetic coelenterazine (CTZ) indicators are developed to quantitatively illuminate human and bovine serum albumins (HSA and BSA) with high specificity. Their functional groups were chemically modified to specifically emit luminescence with HSA and BSA. The CTZ indicators were characterized by assaying the most abundant serum proteins and found that the CTZ indicators S6 and S6h were highly specific to HSA and BSA, respectively. Their colors were dramatically converted from blue, peaked at 480 nm, to yellowish green, peaked at 535 nm, according to the HSA–BSA mixing ratios, wherein the origins and mixing levels of the albumins can be easily determined by their colors and peak positions. The kinetic properties of HSA and BSA were investigated in detail, confirming that the serum albumins catalyze the CTZ indicators, which act as pseudo-luciferases. The catalytic reactions were efficiently inhibited by specific inhibitors, blocking the drug-binding sites I and II of HSA and BSA. Finally, the utility of the CTZ indicators was demonstrated through a quantitative imaging of the real fetal bovine serum (FBS). This study is the first example to show that the CTZ indicators specify HSA and BSA with different colors. This study contributes to the expansion of the toolbox of optical indicators, which efficiently assays serum proteins in physiological samples. Considering that these CTZ indicators immediately report quantitative optical signals with high specificity, they provide solutions to conventional technical hurdles on point-of-care assays of serum albumins.
研究論文（学術雑誌）, 英語

Bright Molecular Strain Probe Templates for Reporting Protein–Protein Interactions
Sung-Bae Kim; Tadaomi Furuta; Genta Kamiya; Nobuo Kitada; Ramasamy Paulmurugan; Shojiro A. Maki
Sensors, MDPI AG, 23巻, 7号, 掲載ページ 3498-3498, 出版日 2023年03月27日, Imaging protein–protein interactions (PPIs) is a hot topic in molecular medicine in the postgenomic sequencing era. In the present study, we report bright and highly sensitive single-chain molecular strain probe templates which embed full-length Renilla luciferase 8.6-535SG (RLuc86SG) or Artificial luciferase 49 (ALuc49) as reporters. These reporters were deployed between FKBP-rapamycin binding domain (FRB) and FK506-binding protein (FKBP) as a PPI model. This unique molecular design was conceptualized to exploit molecular strains of the sandwiched reporters appended by rapamycin-triggered intramolecular PPIs. The ligand-sensing properties of the templates were maximized by interface truncations and substrate modulation. The highest fold intensities, 9.4 and 16.6, of the templates were accomplished with RLuc86SG and ALuc49, respectively. The spectra of the templates, according to substrates, revealed that the colors are tunable to blue, green, and yellow. The putative substrate-binding chemistry and the working mechanisms of the probes were computationally modeled in the presence or absence of rapamycin. Considering that the molecular strain probe templates are applicable to other PPI models, the present approach would broaden the scope of the bioassay toolbox, which harnesses the privilege of luciferase reporters and the unique concept of the molecular strain probes into bioassays and molecular imaging.
研究論文（学術雑誌）

Bioluminescent imaging systems boosting near-infrared signals in mammalian cells
Sung-Bae Kim; Tadaomi Furuta; Yuki Ohmuro-Matsuyama; Nobuo Kitada; Ryo Nishihara; Shojiro A. Maki
Photochemical & Photobiological Sciences, Springer Science and Business Media LLC, 22巻, 6号, 掲載ページ 1267-1278, 出版日 2023年02月03日
研究論文（学術雑誌）

S-Series Coelenterazine-Driven Combinatorial Bioluminescence Imaging Systems for Mammalian Cells
Genta Kamiya; Nobuo Kitada; Tadaomi Furuta; Takashi Hirano; Shojiro A. Maki; Sung-Bae Kim
International Journal of Molecular Sciences, MDPI AG, 24巻, 2号, 掲載ページ 1420-1420, 出版日 2023年01月11日, A unique combinatorial bioluminescence (BL) imaging system was developed for determining molecular events in mammalian cells with various colors and BL intensity patterns. This imaging system consists of one or multiple reporter luciferases and a series of novel coelenterazine (CTZ) analogues named “S-series”. For this study, ten kinds of novel S-series CTZ analogues were synthesized and characterized concerning the BL intensities, spectra, colors, and specificity of various marine luciferases. The characterization revealed that the S-series CTZ analogues luminesce with blue-to-orange-colored BL spectra with marine luciferases, where the most red-shifted BL spectrum peaked at 583 nm. The colors completed a visible light color palette with those of our precedent C-series CTZ analogues. The synthesized substrates S1, S5, S6, and S7 were found to have a unique specificity with marine luciferases, such as R86SG, NanoLuc (shortly, NLuc), and ALuc16. They collectively showed unique BL intensity patterns to identify the marine luciferases together with colors. The marine luciferases, R86SG, NLuc, and ALuc16, were multiplexed into multi-reporter systems, the signals of which were quantitatively unmixed with the specific substrates. When the utility was applied to a single-chain molecular strain probe, the imaging system simultaneously reported three different optical indexes for a ligand, i.e., unique BL intensity and color patterns for identifying the reporters, together with the ligand-specific fold intensities in mammalian cells. This study directs a new combinatorial BL imaging system to specific image molecular events in mammalian cells with multiple optical indexes.
研究論文（学術雑誌）

C-Series Coelenterazine-Driven Bioluminescence Signature Imaging
Genta Kamiya; Nobuo Kitada; Tadaomi Furuta; Takashi Hirano; Shojiro Maki; Sung Bae Kim
International Journal of Molecular Sciences, MDPI AG, 23巻, 21号, 掲載ページ 13047-13047, 出版日 2022年10月27日, The present study introduces a unique BL signature imaging system with novel CTZ analogues named “C-series.” Nine kinds of C-series CTZ analogues were first synthesized, and BL intensity patterns and spectra were then examined according to the marine luciferases. The results show that the four CTZ analogues named C3, C4, C6, and C7, individually or collectively luminesce with completely distinctive BL spectral signatures and intensity patterns according to the luciferases: Renilla luciferase (RLuc), NanoLuc, and artificial luciferase (ALuc). The signatural reporters were multiplexed into a multi-reporter system comprising RLuc8.6-535SG and ALuc16. The usefulness of the signatural reporters was further determined with a multi-probe system that consists of two single-chain probes embedding RLuc8 and ALuc23. This study is a great addition to the study of conventional bioassays with a unique methodology, and for the specification of each signal in a single- or multi-reporter system using unique BL signatures and patterns of reporter luciferases.
研究論文（学術雑誌）

Multiplex quadruple bioluminescent assay system
Genta Kamiya; Nobuo Kitada; Shojiro Maki; Sung Bae Kim
Scientific Reports, 12巻, 掲載ページ 17485, 出版日 2022年10月, 査読付, Alucとウミホタル発光基質(K-シリーズ)の組み合わせで，多色化に成功しており，それを利用して，多重生物発光系の活性標識システムを構築した．
研究論文（学術雑誌）, 英語

Quantum Yield of Near-Infrared Bioluminescence with Firefly Luciferin Analog: AkaLumine
Ryohei Ono; Keita Osawa; Yutaka Takahashi; Yoshifumi Noguchi; Nobuo Kitada; Ryohei Saito-Moriya; Takashi Hirano; Shojiro A. Maki; Keisei Shibata; Hidefumi Akiyama; Ken-ichiro Kanno; Hideyuki Itabashi; Miyabi Hiyama
Journal of Photochemistry and Photobiology A: Chemistry, Elsevier BV, 434巻, 掲載ページ 114270-114270, 出版日 2022年09月, 査読付
研究論文（学術雑誌）

Bioluminescence imaging using d -luciferin and its analogs for visualizing Bdnf expression in living mice; different patterns of bioluminescence signals using distinct luciferase substrates
Mamoru Fukuchi; Satoru Mitazaki; Ryohei Saito-Moriya; Nobuo Kitada; Shojiro A Maki; Hironori Izumi; Hisashi Mori
The Journal of Biochemistry, Oxford University Press (OUP), 出版日 2022年09月01日, Abstract

Brain-derived neurotrophic factor (BDNF) plays a crucial role in numerous brain functions, including memory consolidation. Previously, we generated a Bdnf-Luciferase transgenic (Bdnf-Luc) mouse strain to visualize changes in Bdnf expression using in vivo bioluminescence imaging (BLI). We successfully visualized activity-dependent Bdnf induction in living mouse brains using a d-luciferin analog, TokeOni, which distributes to the brain and produces near-infrared bioluminescence. In this study, we compared the patterns of bioluminescence signals within the whole body of the Bdnf-Luc mice produced by d-luciferin, TokeOni, and seMpai, another d-luciferin analog that produces a near-infrared light. As recently reported, hepatic background signals were observed in wild-type mice when using TokeOni. Bioluminescence signals were strongly observed from the region containing the liver when using d-luciferin and TokeOni. Additionally, we detected signals from the brain when using TokeOni. Compared with d-luciferin and TokeOni, signals were widely detected in the whole body of Bdnf-Luc mice by seMpai. The signals produced by seMpai were strong in the regions containing skeletal muscles in particular. Taken together, the patterns of bioluminescence signals in Bdnf-Luc mice vary when using different luciferase substrates. Therefore, the expression of Bdnf in tissues and organs of interest could be visualized by selecting an appropriate substrate.
研究論文（学術雑誌）

Absorption Spectra for Firefly Bioluminescence Substrate Analog: TokeOni in Various pH Solutions
Haruhisa Ogawa; Ryohei Ono; Yoshifumi Noguchi; Nobuo Kitada; Ryohei Saito‐Moriya; Shojiro A. Maki; Hidefumi Akiyama; Hideyuki Itabashi; Miyabi Hiyama
Photochemistry and Photobiology, Wiley, 97巻, 5号, 掲載ページ 1016-1022, 出版日 2021年09月, 査読付, AkaLumine hydrochloride, named TokeOni, is one of the firefly luciferin analogs, and its reaction with firefly luciferase produces near-infrared (NIR) bioluminescence. Prior to studying the bioluminescence mechanism, basic knowledge about the chemical structures, electronic states, and absorption properties of TokeOni at various pH values of solution has to be acquired. In this paper, the absorption spectra for TokeOni and AkaLumine at pH 2-10 were measured. Density functional theory (DFT) calculations, time-dependent DFT calculations, and the vibrational analyses were carried out. The absorption spectra indicate that the chemical forms of TokeOni in solutions are same as those of AkaLumine. The peaks at pH 7-10 in the absorption spectra correspond to the excitation from the ground state of a carboxylate anion of AkaLumine, the peak at pH 2 corresponds to the excitation from the ground state of a carboxylate anion with an N-protonated thiazoline ring and N-protonated dimethylamino group of AkaLumine, and the peak at pH 4 corresponds to the excitation from the ground state of a carboxylate anion with an N-protonated thiazoline ring of AkaLumine.
研究論文（学術雑誌）, 英語

Development of phenyl oligoene-type firefly luciferin analogues with extended π-electronic conjugation for near-infrared bioluminescence
Genta Kamiya; Nobuo Kitada; Ryohei Saito-Moriya; Rika Obata; Satoshi Iwano; Atsushi Miyawaki; Takashi Hirano; Shojiro Maki
Chemistry Letters, The Chemical Society of Japan, 出版日 2021年05月20日
研究論文（学術雑誌）

Synthesis of polyenylpyrrole derivatives with selective growth inhibitory activity against T-cell acute lymphoblastic leukemia cells
Chihiro Yoshida; Tomoya Higashi; Yoshifumi Hachiro; Yuki Fujita; Takuya Yagi; Azusa Takechi; Chihiro Nakata; Kazuya Miyashita; Nobuo Kitada; Ryohei Saito; Rika Obata; Takashi Hirano; Takahiko Hara; Shojiro A. Maki
Bioorganic & Medicinal Chemistry Letters, Elsevier BV, 37巻, 掲載ページ 127837-127837, 出版日 2021年04月
研究論文（学術雑誌）

How to Select Firefly Luciferin Analogues for In Vivo Imaging
Ryohei Saito-Moriya; Jun Nakayama; Genta Kamiya; Nobuo Kitada; Rika Obata; Shojiro A. Maki; Hiroshi Aoyama
International Journal of Molecular Sciences, MDPI AG, 22巻, 4号, 掲載ページ 1848-1848, 出版日 2021年02月12日, Bioluminescence reactions are widely applied in optical in vivo imaging in the life science and medical fields. Such reactions produce light upon the oxidation of a luciferin (substrate) catalyzed by a luciferase (enzyme), and this bioluminescence enables the quantification of tumor cells and gene expression in animal models. Many researchers have developed single-color or multicolor bioluminescence systems based on artificial luciferin analogues and/or luciferase mutants, for application in vivo bioluminescence imaging (BLI). In the current review, we focus on the characteristics of firefly BLI technology and discuss the development of luciferin analogues for high-resolution in vivo BLI. In addition, we discuss the novel luciferin analogues TokeOni and seMpai, which show potential as high-sensitivity in vivo BLI reagents.
研究論文（学術雑誌）

Color-tunable bioluminescence imaging portfolio for cell imaging
Shota Tamaki; Nobuo Kitada; Masahiro Kiyama; Rika Fujii; Takashi Hirano; Sung Bae Kim; Shojiro Maki
Scientific Reports, Springer Science and Business Media LLC, 11巻, 1号, 出版日 2021年01月26日, Abstract

The present study describes a color-tunable imaging portfolio together with twelve novel coelenterazine (CTZ) analogues. The three groups of CTZ analogues create diverse hues of bioluminescence (BL) ranging from blue to far red with marine luciferases. We found that the hue completes the whole color palette in the visible region and shows red-shifted BL with a marine luciferase: for example, Renilla luciferase 8 (RLuc8) and Artificial Luciferase 16 (ALuc16) show 187 nm- and 105 nm-redshifted spectra, respectively, by simply replacing the substrate CTZ with 1d. The optical properties of the new CTZ analogues were investigated such as the kinetic parameters, dose dependency, and luciferase specificity. The 2-series CTZ analogues interestingly have specificity to ALucs and are completely dark with RLuc derivatives, and 3d is highly specific to only NanoLuc. We further determined the theoretical background of the red-shifted BL maximum wavelengths (λ_BL) values according to the extended π conjugation of the CTZ backbone using Density Functional Theory (DFT) calculations. This color-tunable BL imaging system provides a useful multicolor imaging portfolio that efficiently images molecular events in mammalian cells.
研究論文（学術雑誌）

High Sensitivity In Vivo Imaging of Cancer Metastasis Using a Near-Infrared Luciferin Analogue seMpai.
Jun Nakayama; Ryohei Saito; Yusuke Hayashi; Nobuo Kitada; Shota Tamaki; Yuxuan Han; Kentaro Semba; Shojiro A Maki
International journal of molecular sciences, 21巻, 21号, 出版日 2020年10月24日, 国際誌, Bioluminescence imaging (BLI) is useful to monitor cell movement and gene expression in live animals. However, D-luciferin has a short wavelength (560 nm) which is absorbed by tissues and the use of near-infrared (NIR) luciferin analogues enable high sensitivity in vivo BLI. The AkaLumine-AkaLuc BLI system (Aka-BLI) can detect resolution at the single-cell level; however, it has a clear hepatic background signal. Here, to enable the highly sensitive detection of bioluminescence from the surrounding liver tissues, we focused on seMpai (C15H16N3O2S) which has been synthesized as a luciferin analogue and has high luminescent abilities as same as AkaLumine. We demonstrated that seMpai BLI could detect micro-signals near the liver without any background signal. The solution of seMpai was neutral; therefore, seMpai imaging did not cause any adverse effect in mice. seMpai enabled a highly sensitive in vivo BLI as compared to previous techniques. Our findings suggest that the development of a novel mutated luciferase against seMpai may enable a highly sensitive BLI at the single-cell level without any background signal. Novel seMpai BLI system can be used for in vivo imaging in the fields of life sciences and medicine.
研究論文（学術雑誌）, 英語

Development of near-infrared firefly luciferin analogue reacted with wild-type and mutant luciferases.
Nobuo Kitada; Ryohei Saito; Rika Obata; Satoshi Iwano; Kazuma Karube; Atsushi Miyawaki; Takashi Hirano; Shojiro A Maki
Chirality, 32巻, 7号, 掲載ページ 922-931, 出版日 2020年07月, 国際誌, Interestingly, only the D-form of firefly luciferin produces light by luciferin-luciferase (L-L) reaction. Certain firefly luciferin analogues with modified structures maintain bioluminescence (BL) activity; however, all L-form luciferin analogues show no BL activity. To this date, our group has developed luciferin analogues with moderate BL activity that produce light of various wavelengths. For in vivo bioluminescence imaging, one of the important factors for detection sensitivity is tissue permeability of the number of photons emitted by L-L reaction, and the wavelengths of light in the near-infrared (NIR) range (700-900 nm) are most appropriate for the purpose. Some NIR luciferin analogues by us had performance for in vivo experiments to make it possible to detect photons from deep target tissues in mice with high sensitivity, whereas only a few of them can produce NIR light by the L-L reactions with wild-type luciferase and/or mutant luciferase. Based on the structure-activity relationships, we designed and synthesized here a luciferin analogue with the 5-allyl-6-dimethylamino-2-naphthylethenyl moiety. This analogue exhibited NIR BL emissions with wild-type luciferase (λmax = 705 nm) and mutant luciferase AlaLuc (λmax = 655 nm).
研究論文（学術雑誌）, 英語

Toward bioluminescence in the near-infrared region: Tuning the emission wavelength of firefly luciferin analogues by allyl substitution
Nobuo Kitada; Tsuyoshi Saitoh; Yuma Ikeda; Satoshi Iwano; Rika Obata; Haruki Niwa; Takashi Hirano; Atsushi Miyawaki; Koji Suzuki; Shigeru Nishiyama; Shojiro A. Maki
Tetrahedron Letters, 59巻, 12号, 出版日 2018年, 査読付
研究論文（学術雑誌）

An allylated firefly luciferin analogue with luciferase specific response in living cells
Ikeda, Yuma; Saitoh, Tsuyoshi; Niwa, Kazuki; Nakajima, Takahiro; Kitada, Nobuo; Maki, Shojiro A.; Sato, Moritoshi; Citterio, Daniel; Nishiyama, Shigeru; Suzuki, Koji
Chem. Commun., The Royal Society of Chemistry, 54巻, 出版日 2018年, 査読付
研究論文（学術雑誌）

Aspiration Risk Detection Using Oral Administration of Fluorescent Food - Preliminary Experiments Using Meat Phantoms
Takahiro Suzuki; Ryohei Saito; Nobuo Kitada; Takuji Koike; Shojiro Maki; Yukihiro Michiwaki; Goro Nishimura; Haruki Niwa; Yukio Yamada
2017 IEEE INTERNATIONAL CONFERENCE ON CYBORG AND BIONIC SYSTEMS (CBS), IEEE, 掲載ページ 24-28, 出版日 2017年, 査読付
研究論文（国際会議プロシーディングス）, 英語

Polymeric one- and two-dimensional copper(i) iodide complexes showing photoluminescence tunable by azaaromatic ligands
Kitada, Nobuo; Ishida, Takayuki
CrystEngComm, The Royal Society of Chemistry, 16巻, 出版日 2014年, 査読付
研究論文（学術雑誌）

近赤外発光試薬seMpaiによるがん転移のイメージング
森屋(齊藤)亮平; 森屋(齊藤)亮平; 森屋(齊藤)亮平; 中山淳; 北田昇雄; 北田昇雄; 牧昌次郎; 牧昌次郎
出版日 2021年, 日本癌学会学術総会抄録集(Web), 80th巻, 202102246186686282

近赤外蛍光を用いた咽頭残留の非侵襲検出法の開発:ファントムを用いた検出能評価
田代剛大; 山田幸生; 丹羽治樹; 牧昌次郎; 牧昌次郎; 北田昇雄; 斉藤亮平; 小池卓二; 小池卓二; 道脇幸博; 西村吾朗
出版日 2020年, Optics & Photonics Japan講演予稿集(CD-ROM), 2020巻, 202102274483914423

近赤外蛍光を用いた非侵襲咽頭残留検出装置のヒトにおける検出性評価
田代剛大; 鈴木嵩弘; 山田幸生; 丹羽治樹; 牧昌次郎; 牧昌次郎; 北田昇雄; 齊藤亮平; 小池卓二; 小池卓二; 道脇幸博; 西村吾朗
出版日 2020年, 日本機械学会年次大会講演論文集(CD-ROM), 2020巻, 2424-2667, 202202221715279029

誤嚥検査のための近赤外蛍光を用いた咽頭残留検出システムの開発
田代剛大; 鈴木崇弘; 山田幸生; 丹羽治樹; 牧昌次郎; 牧昌次郎; 北田昇雄; 斉藤亮平; 小池卓二; 小池卓二; 道脇幸博; 西村吾朗
出版日 2019年, Optics & Photonics Japan講演予稿集(CD-ROM), 2019巻, 202002289348370842

in vivo光イメージングを志向したNIRルシフェリンアナログ
北田昇雄; 齊藤亮平; 口丸高弘; 近藤科江; 中山淳; 中山淳; 仙波憲太郎; 牧昌次郎; 牧昌次郎
出版日 2019年, 日本癌学会学術総会抄録集(Web), 78th巻, 202002284518626981

ホタルルシフェリンアナログのアリル基導入による波長制御
北田昇雄; 木山正啓; 齊藤亮平; 斉藤毅; 西山繁; 丹羽治樹; 平野誉; 牧昌次郎
出版日 2017年, 日本化学会春季年会講演予稿集(CD-ROM), 97th巻, 201702284117570298

ホタルルシフェリンアナログのアリル基導入による波長制御
北田昇雄; 木山正啓; 齊藤亮平; 斉藤毅; 西山繁; 丹羽治樹; 平野誉; 牧昌次郎; 牧昌次郎
出版日 2017年, 有機電子移動化学討論会講演要旨集, 41st巻, 201702242781624321

世界最長波長で発光する新規ルシフェリンアナログの創製
軽部一磨; 北田昇雄; 三浦千弥; 岩野智; 平野誉; 丹羽治樹; 牧昌次郎; 斉藤毅; 西山繁
出版日 2014年, 日本化学会講演予稿集, 94th巻, 4号, 0285-7626, 201402247592690770

世界最長波長で発光する新規ホタルルシフェリンアナログの創製
軽部一磨; 北田昇雄; 三浦千弥; 岩野智; 平野誉; 丹羽治樹; 牧昌次郎; 斉藤毅; 西山繁
出版日 2013年, 電気化学秋季大会講演要旨集, 2013巻, 201302226074753372

世界最長波長で発光する新規ホタルルシフェリンアナログの創製
軽部一磨; 北田昇雄; 三浦千弥; 岩野智; 平野誉; 丹羽治樹; 牧昌次郎; 斉藤毅; 西山繁
出版日 2013年, 日本分子生物学会年会プログラム・要旨集(Web), 36th巻, 201402217093474830

世界最長波長で発光する新規ホタルルシフェリンアナログの創製
軽部一磨; 北田昇雄; 三浦千弥; 岩野智; 平野誉; 丹羽治樹; 牧昌次郎; 斉藤毅; 西山繁
出版日 2013年, 有機電子移動化学討論会講演要旨集, 37th巻, 201302212050717692

発光細胞アレイを用いた化学物質のホルモン様活性・健康リスク評価基盤の創出
金 誠培; チッテリオ ダニエル; 北田 昇雄; 牧 昌次郎; 坂間 亮浩
日本学術振興会, 科学研究費助成事業, 国立研究開発法人産業技術総合研究所, 国際共同研究加速基金(海外連携研究), 23KK0101
研究期間 2023年09月08日 - 2029年03月31日

ホタル生物発光システムの大規模スクリーニング研究
北田 昇雄
日本学術振興会, 科学研究費助成事業, 電気通信大学, 若手研究, 24K17835
研究期間 2024年04月01日 - 2027年03月31日

ホタル発光系における特異的発光を示す新規ルシフェリンアナログの構造活性相関研究
北田 昇雄
日本学術振興会, 科学研究費助成事業, 電気通信大学, 特別研究員奨励費, 高感度なイメージング材料の創製にあたって、高輝度で長波長の発光を示す発光材料の合成が必要である。そこで本年度も高輝度化と長波長化の2つのアプローチで研究を行った。 ・アリル基の導入による発光波長の長波長化 ルシフェリンアナログにアリル基を導入することで、10～40 nmの長波長化シフトが起こることが明らかとなった。その結果、685 nmの発光波長を示すアナログAと690 nmの発光波長を示すアナログBの合成に成功した。 これらの化合物において、in vivoイメージング実験を行ったところ、天然のD-Luciferinや当研究室で開発されたAkaLumineよりも有用な結果を得ることは出来なかった。長波長化により生体透過性は高まっていると思われるが、構造の改変による輝度の低下が感度の低下の大きな要因であると考えられる。今後、後述の高輝度化の技術や、酵素改変による輝度向上を目指していく必要がある。 ・反応中間体の合成による発光特性の評価 ホタルの生物発光はアデニル化と酸素化の2段階の反応で起きていることが知られている。この1段階目のアデニル化の反応速度は遅く律速であるため、発光輝度低下の要因となっている。そこでホタルルシフェリンの発光中間体である、アデニル化ルシフェリン（AMP化体）を人工的に合成し、発光反応をさせることで反応速度が飛躍的に向上し単位時間あたりの輝度が1000倍近く向上することが知られている。また、このAMP化体を他のヌクレオチドに改変しても発光活性が失われないことも明らかとなっている。そこで、様々なヌクレオチドや糖と天然ルシフェリンの発光中間体アナログを合成し、その発光活性を明らかとした。いずれの化合物との中間体アナログも発光活性を持つことが明らかとなった。これらの反応中間体は非常に不安定であるため、構造改変による安定化を目指していく。, 16J10251
研究期間 2016年04月22日 - 2018年03月31日