Nitrogen-containing heterocyclic compounds

Nucleobase

Carbonaceous chondrites

Amino acids

Natural sciences, Space and planetary science, extraterrestrial organics

Apr. 2024 - Present
Japan Agency for Marine-Earth Science and Technology, Biogeochemistry Research Center, Postdoctoral Fellow

Apr. 2021 - Mar. 2024
Japan Society for the Promotion of Science, JSPS Research Fellow(PD)

Apr. 2018 - Mar. 2021
Japan Society for the Promotion of Science, JSPS Research Fellow(DC1)

Apr. 2018 - May 2019
Japan Society for the Promotion of Science, Overseas Challenge Program for Young Researchers Grant

Apr. 2018 - Mar. 2021, Kyushu University, Graduate School of Sciences, Department of Earth and Planetary Sciences

Apr. 2016 - Mar. 2018, Kyushu University, Graduate School of Sciences, Department of Earth and Planetary Sciences

Apr. 2012 - Mar. 2016, Kyushu University, School of Sciences, Department of Earth and Planetary Sciences

Yoshihiro Furukawa; Sako Sunami; Yoshinori Takano; Toshiki Koga; Yuta Hirakawa; Yasuhiro Oba; Hiroshi Naraoka; Daisuke Saigusa; Takaaki Yoshikawa; Satoru Tanaka; Daniel P. Glavin; Jason P. Dworkin; Harold C. Connolly; Dante S. Lauretta
Bio-essential sugars in samples from asteroid Bennu
NATURE GEOSCIENCE, 02 Dec. 2025

Yuta Hirakawa; Toshiki Koga; Takahiro Suzuki; Naohiko Ohkouchi; Yoshinori Takano
Analytical Development for Detecting Femtomole-Level Organophosphorus Compounds in Biogeochemical Samples by Ion Chromatography/High-Resolution Mass Spectrometry
ACS Omega, 31 Aug. 2025
10, 36, 42061, 42067

Toshiki Koga; Yasuhiro Oba; Yoshinori Takano; Hiroshi Naraoka; Nanako Ogawa; Kazunori Sasaki; Hajime Sato; Toshihiro Yoshimura; Naohiko Ohkouchi
A complete set of canonical nucleobases in asteroid Ryugu demonstrates their prevalence in carbonaceous asteroids
11 Aug. 2025

Toshiki Koga; Yoshinori Takano; Nanako O. Ogawa; Emily H. Hollingsworth; Yasuhiro Oba; Naohiko Ohkouchi
Compound-Specific Carbon and Nitrogen Isotopic Analyses of Underivatized Pyrimidine and Purine Nucleobases
ACS Earth and Space Chemistry, 03 Mar. 2025
9, 3, 424, 432

Daniel P. Glavin; Jason P. Dworkin; Conel M.O.D. Alexander; José C. Aponte; Allison A. Baczynski; Jessica J. Barnes; Hans A. Bechtel; Eve L. Berger; Aaron S. Burton; Paola Caselli; Angela H. Chung; Simon J. Clemett; George D. Cody; Gerardo Dominguez; Jamie E. Elsila; Kendra K. Farnsworth; Dionysis I. Foustoukos; Katherine H. Freeman; Yoshihiro Furukawa; Zack Gainsforth; Heather V. Graham; Tommaso Grassi; Barbara Michela Giuliano; Victoria E. Hamilton; Pierre Haenecour; Philipp R. Heck; Amy E. Hofmann; Christopher H. House; Yongsong Huang; Hannah H. Kaplan; Lindsay P. Keller; Bumsoo Kim; Toshiki Koga; Michael Liss; Hannah L. McLain; Matthew A. Marcus; Mila Matney; Timothy J. McCoy; Ophélie M. McIntosh; Angel Mojarro; Hiroshi Naraoka; Ann N. Nguyen; Michel Nuevo; Joseph A. Nuth; Yasuhiro Oba; Eric T. Parker; Tanya S. Peretyazhko; Scott A. Sandford; Ewerton Santos; Philippe Schmitt-Kopplin; Frederic Seguin; Danielle N. Simkus; Anique Shahid; Yoshinori Takano; Kathie L. Thomas-Keprta; Havishk Tripathi; Gabriella Weiss; Yuke Zheng; Nicole G. Lunning; Kevin Righter; Harold C. Connolly; Dante S. Lauretta
Abundant ammonia and nitrogen-rich soluble organic matter in samples from asteroid (101955) Bennu
Nature Astronomy, 2025

Toshihiro Yoshimura; Daisuke Araoka; Hiroshi Naraoka; Saburo Sakai; Nanako O. Ogawa; Hisayoshi Yurimoto; Mayu Morita; Morihiko Onose; Tetsuya Yokoyama; Martin Bizzarro; Satoru Tanaka; Naohiko Ohkouchi; Toshiki Koga; Jason P. Dworkin; Tomoki Nakamura; Takaaki Noguchi; Ryuji Okazaki; Hikaru Yabuta; Kanako Sakamoto; Toru Yada; Masahiro Nishimura; Aiko Nakato; Akiko Miyazaki; Kasumi Yogata; Masanao Abe; Tatsuaki Okada; Tomohiro Usui; Makoto Yoshikawa; Takanao Saiki; Satoshi Tanaka; Fuyuto Terui; Satoru Nakazawa; Sei-ichiro Watanabe; Yuichi Tsuda; Shogo Tachibana; Yoshinori Takano
Breunnerite grain and magnesium isotope chemistry reveal cation partitioning during aqueous alteration of asteroid Ryugu
Nature Communications, 05 Sep. 2024
15, 1

Yoshinori Takano; Hiroshi Naraoka; Jason P. Dworkin; Toshiki Koga; Kazunori Sasaki; Hajime Sato; Yasuhiro Oba; Nanako O. Ogawa; Toshihiro Yoshimura; Kenji Hamase; Naohiko Ohkouchi; Eric T. Parker; José C. Aponte; Daniel P. Glavin; Yoshihiro Furukawa; Junken Aoki; Kuniyuki Kano; Shin-ichiro M. Nomura; Francois-Regis Orthous-Daunay; Philippe Schmitt-Kopplin; Aogu Furusho; Minako Hashiguchi; Kazuhiko Fukushima; Dan Aoki; Hannah L. McLain; Jamie E. Elsila; Heather V. Graham; John M. Eiler; Norbert Hertkorn; Alexander Ruf; Cédric Wolters; Junko Isa; Véronique Vuitton; Roland Thissen; Saburo Sakai; Haruna Sugahara; Hajime Mita; Yoshito Chikaraishi; Takaaki Yoshikawa; Satoru Tanaka; Mayu Morita; Morihiko Onose; Daisuke Araoka; Fumie Kabashima; Kosuke Fujishima; Hajime Sato; Tomoya Yamazaki; Yuki Kimura; Hisayoshi Yurimoto; Tomoki Nakamura; Takaaki Noguchi; Ryuji Okazaki; Hikaru Yabuta; Kanako Sakamoto; Toru Yada; Masahiro Nishimura; Aiko Nakato; Akiko Miyazaki; Kasumi Yogata; Masanao Abe; Tatsuaki Okada; Tomohiro Usui; Makoto Yoshikawa; Takanao Saiki; Satoshi Tanaka; Fuyuto Terui; Satoru Nakazawa; Sei-ichiro Watanabe; Yuichi Tsuda; Shogo Tachibana
Primordial aqueous alteration recorded in water-soluble organic molecules from the carbonaceous asteroid (162173) Ryugu
Nature Communications, 10 Jul. 2024
15, 1

Aogu Furusho; Chiharu Ishii; Takeyuki Akita; Mai Oyaide; Masashi Mita; Hiroshi Naraoka; Yoshinori Takano; Jason P. Dworkin; Yasuhiro Oba; Toshiki Koga; Kazuhiko Fukushima; Dan Aoki; Minako Hashiguchi; Hajime Mita; Yoshito Chikaraishi; Naohiko Ohkouchi; Nanako O. Ogawa; Saburo Sakai; Daniel P. Glavin; Jamie E. Elsila; Eric T. Parker; José C. Aponte; Hannah L. McLain; Francois-Regis Orthous-Daunay; Véronique Vuitton; Roland Thissen; Cédric Wolters; Philippe Schmitt-Kopplin; Alexander Ruf; Junko Isa; Norbert Hertkorn; John M. Eiler; Toshihiro Yoshimura; Haruna Sugahara; Heather V. Graham; Yoshihiro Furukawa; Daisuke Araoka; Satoru Tanaka; Takaaki Yoshikawa; Fumie Kabashima; Kazunori Sasaki; Hajime Sato; Tomoya Yamazaki; Morihiko Onose; Mayu Morita; Yuki Kimura; Kuniyuki Kano; Junken Aoki; Kosuke Fujishima; Shin-ichiro Nomura; Shogo Tachibana; Tomoki Nakamura; Takaaki Noguchi; Ryuji Okazaki; Hikaru Yabuta; Hisayoshi Yurimoto; Kanako Sakamoto; Toru Yada; Masahiro Nishimura; Aiko Nakato; Akiko Miyazaki; Kasumi Yogata; Masanao Abe; Tomohiro Usui; Makoto Yoshikawa; Takanao Saiki; Satoshi Tanaka; Fuyuto Terui; Satoru Nakazawa; Tatsuaki Okada; Sei-ichiro Watanabe; Yuichi Tsuda; Kenji Hamase
Enantioselective three-dimensional high-performance liquid chromatographic determination of amino acids in the Hayabusa2 returned samples from the asteroid Ryugu
Journal of Chromatography Open, May 2024
100134, 100134

Daniel P. Glavin; Scott A. Eckley; José C. Aponte; Eve L. Berger; Aaron S. Burton; Jason P. Dworkin; Jamie E. Elsila; Frank T. Ferguson; Yoshihiro Furukawa; Heather V. Graham; Toshiki Koga; Michael Liss; Hannah L. McLain; Hiroshi Naraoka; Yasuhiro Oba; Eric T. Parker; Kevin Righter; Philippe Schmitt-Kopplin; Danielle N. Simkus; Yoshinori Takano; Harold C. Connolly; Dante S. Lauretta
Investigating the impact of x-ray computed tomography imaging on soluble organic matter in the Murchison meteorite: Implications for Bennu sample analyses
Meteoritics and Planetary Science, Jan. 2024
59, 1, 105, 133

Toshiki Koga; Yoshinori Takano; Yasuhiro Oba; Hiroshi Naraoka; Naohiko Ohkouchi
Abundant extraterrestrial purine nucleobases in the Murchison meteorite: Implications for a unified mechanism for purine synthesis in carbonaceous chondrite parent bodies
Geochimica et Cosmochimica Acta, Jan. 2024
365, 253, 265
Lead

Sarah S. Zeichner; José C. Aponte; Surjyendu Bhattacharjee; Guannan Dong; Amy E. Hofmann; Jason P. Dworkin; Daniel P. Glavin; Jamie E. Elsila; Heather V. Graham; Hiroshi Naraoka; Yoshinori Takano; Shogo Tachibana; Allison T. Karp; Kliti Grice; Alex I. Holman; Katherine H. Freeman; Hisayoshi Yurimoto; Tomoki Nakamura; Takaaki Noguchi; Ryuji Okazaki; Hikaru Yabuta; Kanako Sakamoto; Toru Yada; Masahiro Nishimura; Aiko Nakato; Akiko Miyazaki; Kasumi Yogata; Masanao Abe; Tatsuaki Okada; Tomohiro Usui; Makoto Yoshikawa; Takanao Saiki; Satoshi Tanaka; Fuyuto Terui; Satoru Nakazawa; Sei-ichiro Watanabe; Yuichi Tsuda; Kenji Hamase; Kazuhiko Fukushima; Dan Aoki; Minako Hashiguchi; Hajime Mita; Yoshito Chikaraishi; Naohiko Ohkouchi; Nanako O. Ogawa; Saburo Sakai; Eric T. Parker; Hannah L. McLain; Francois-Regis Orthous-Daunay; Véronique Vuitton; Cédric Wolters; Philippe Schmitt-Kopplin; Norbert Hertkorn; Roland Thissen; Alexander Ruf; Junko Isa; Yasuhiro Oba; Toshiki Koga; Toshihiro Yoshimura; Daisuke Araoka; Haruna Sugahara; Aogu Furusho; Yoshihiro Furukawa; Junken Aoki; Kuniyuki Kano; Shin-ichiro M. Nomura; Kazunori Sasaki; Hajime Sato; Takaaki Yoshikawa; Satoru Tanaka; Mayu Morita; Morihiko Onose; Fumie Kabashima; Kosuke Fujishima; Tomoya Yamazaki; Yuki Kimura; John M. Eiler
Polycyclic aromatic hydrocarbons in samples of Ryugu formed in the interstellar medium
Science, 22 Dec. 2023
382, 6677, 1411, 1416

Philippe Schmitt-Kopplin; Norbert Hertkorn; Mourad Harir; Franco Moritz; Marianna Lucio; Lydie Bonal; Eric Quirico; Yoshinori Takano; Jason P. Dworkin; Hiroshi Naraoka; Shogo Tachibana; Tomoki Nakamura; Takaaki Noguchi; Ryuji Okazaki; Hikaru Yabuta; Hisayoshi Yurimoto; Kanako Sakamoto; Toru Yada; Masahiro Nishimura; Aiko Nakato; Akiko Miyazaki; Kasumi Yogata; Masanao Abe; Tomohiro Usui; Makoto Yoshikawa; Takanao Saiki; Satoshi Tanaka; Fuyuto Terui; Satoru Nakazawa; Tatsuaki Okada; Sei-ichiro Watanabe; Yuichi Tsuda; Kenji Hamase; Aogu Furusho; Minako Hashiguchi; Kazuhiko Fukushima; Dan Aoki; José C. Aponte; Eric T. Parker; Daniel P. Glavin; Hannah L. McLain; Jamie E. Elsila; Heather V. Graham; John M. Eiler; Alexander Ruf; Francois-Regis Orthous-Daunay; Junko Isa; Véronique Vuitton; Roland Thissen; Nanako O. Ogawa; Saburo Sakai; Toshihiro Yoshimura; Toshiki Koga; Haruna Sugahara; Naohiko Ohkouchi; Hajime Mita; Yoshihiro Furukawa; Yasuhiro Oba
Soluble organic matter Molecular atlas of Ryugu reveals cold hydrothermalism on C-type asteroid parent body
Nature Communications, 16 Oct. 2023
14, 1
[Reviewed]

Yoshimura, T; Takano, Y; Naraoka, H; Koga, T; Araoka, D; Ogawa; N.O. et al.
Chemical evolution of primordial salts and organic sulfur molecules in the asteroid 162173 Ryugu
Nature Communications, Sep. 2023
14,, 1, Article number: 5284.
[Reviewed]

Yasuhiro Oba; Toshiki Koga; Yoshinori Takano; Nanako O. Ogawa; Naohiko Ohkouchi; Kazunori Sasaki; Hajime Sato; Daniel P. Glavin; Jason P. Dworkin; Hiroshi Naraoka; Shogo Tachibana; Hisayoshi Yurimoto; Tomoki Nakamura; Takaaki Noguchi; Ryuji Okazaki; Hikaru Yabuta; Kanako Sakamoto; Toru Yada; Masahiro Nishimura; Aiko Nakato; Akiko Miyazaki; Kasumi Yogata; Masanao Abe; Tatsuaki Okada; Tomohiro Usui; Makoto Yoshikawa; Takanao Saiki; Satoshi Tanaka; Fuyuto Terui; Satoru Nakazawa; Sei-ichiro Watanabe; Yuichi Tsuda
Uracil in the carbonaceous asteroid (162173) Ryugu
Nature Communications, 21 Mar. 2023
14, 1

Hiroshi Naraoka; Yoshinori Takano; Jason P. Dworkin; Yasuhiro Oba; Kenji Hamase; Aogu Furusho; Nanako O. Ogawa; Minako Hashiguchi; Kazuhiko Fukushima; Dan Aoki; Philippe Schmitt-Kopplin; José C. Aponte; Eric T. Parker; Daniel P. Glavin; Hannah L. McLain; Jamie E. Elsila; Heather V. Graham; John M. Eiler; Francois-Regis Orthous-Daunay; Cédric Wolters; Junko Isa; Véronique Vuitton; Roland Thissen; Saburo Sakai; Toshihiro Yoshimura; Toshiki Koga; Naohiko Ohkouchi; Yoshito Chikaraishi; Haruna Sugahara; Hajime Mita; Yoshihiro Furukawa; Norbert Hertkorn; Alexander Ruf; Hisayoshi Yurimoto; Tomoki Nakamura; Takaaki Noguchi; Ryuji Okazaki; Hikaru Yabuta; Kanako Sakamoto; Shogo Tachibana; Harold C. Connolly; Dante S. Lauretta; Masanao Abe; Toru Yada; Masahiro Nishimura; Kasumi Yogata; Aiko Nakato; Miwa Yoshitake; Ayako Suzuki; Akiko Miyazaki; Shizuho Furuya; Kentaro Hatakeda; Hiromichi Soejima; Yuya Hitomi; Kazuya Kumagai; Tomohiro Usui; Tasuku Hayashi; Daiki Yamamoto; Ryota Fukai; Kohei Kitazato; Seiji Sugita; Noriyuki Namiki; Masahiko Arakawa; Hitoshi Ikeda; Masateru Ishiguro; Naru Hirata; Koji Wada; Yoshiaki Ishihara; Rina Noguchi; Tomokatsu Morota; Naoya Sakatani; Koji Matsumoto; Hiroki Senshu; Rie Honda; Eri Tatsumi; Yasuhiro Yokota; Chikatoshi Honda; Tatsuhiro Michikami; Moe Matsuoka; Akira Miura; Hirotomo Noda; Tetsuya Yamada; Keisuke Yoshihara; Kosuke Kawahara; Masanobu Ozaki; Yu-ichi Iijima; Hajime Yano; Masahiko Hayakawa; Takahiro Iwata; Ryudo Tsukizaki; Hirotaka Sawada; Satoshi Hosoda; Kazunori Ogawa; Chisato Okamoto; Naoyuki Hirata; Kei Shirai; Yuri Shimaki; Manabu Yamada; Tatsuaki Okada; Yukio Yamamoto; Hiroshi Takeuchi; Atsushi Fujii; Yuto Takei; Kento Yoshikawa; Yuya Mimasu; Go Ono; Naoko Ogawa; Shota Kikuchi; Satoru Nakazawa; Fuyuto Terui; Satoshi Tanaka; Takanao Saiki; Makoto Yoshikawa; Sei-ichiro Watanabe; Yuichi Tsuda
Soluble organic molecules in samples of the carbonaceous asteroid (162173) Ryugu
Science, 24 Feb. 2023
379, 6634, eabn9033

Yasuhiro Oba; Yoshinori Takano; Yoshihiro Furukawa; Toshiki Koga; Daniel P. Glavin; Jason P. Dworkin; Hiroshi Naraoka
Identifying the wide diversity of extraterrestrial purine and pyrimidine nucleobases in carbonaceous meteorites
Nature Communications, Dec. 2022
13, 1
[Reviewed]

Minako Hashiguchi; Dan Aoki; Kazuhiko Fukushima; Hiroshi Naraoka; Yoshinori Takano; Dworkin P. Jason; Aponte C. Jose; Elsila E. Jamie; Eiler M. John; Yoshihiro Furukawa; Aogu Furusho; Glavin P. Daniel; Heather V. Graham; Kenji Hamase; Hertkorn Norbert; Junko Isa; Toshiki Koga; McLain L. Hannah; Hajime Mita; Yasuhiro Oba; Nanako O. Ogawa; Naohiko Ohkouchi; Francois-Regis Orthous-Daunay; Eric T. Parker; Ruf Alexander; Saburo Sakaki; Schmitt-Kopplin Philippe; Haruna Sugahara; Thissen Roland; Vuitton Véronique; Cédric Wolters; Toshihiro Yoshimura; Hisayoshi Yurimoto; Tomoki Nakamura; Takaaki Noguchi; Ryuji Okazaki; Hikaru Yabuta; Kanako Sakamoto; Shogo Tachibana; Toru Yada; Masahiro Nishimura; Aiko Nakato; Akiko Miyazaki; Kasumi Yogata; Masanao Abe; Tomohiro Usui; Makoto Yoshikawa; Takanao Saiki; Satoshi Tanaka; Fuyuto Terui; Satoru Nakazawa; Sei-ichiro Watanabe; Yuichi Tsuda
The spatial distribution of soluble organic matter and its relationship to minerals in the asteroid (162173) Ryugu.
25 Jul. 2022

Toshiki Koga; Hiroshi Naraoka
Synthesis of Amino Acids from Aldehydes and Ammonia: Implications for Organic Reactions in Carbonaceous Chondrite Parent Bodies
ACS Earth and Space Chemistry, 22 Apr. 2022
[Reviewed]
Lead

Toshiki Koga; Eric T. Parker; Hannah L. McLain; José C. Aponte; Jamie E. Elsila; Jason P. Dworkin; Daniel P. Glavin; Hiroshi Naraoka
Extraterrestrial hydroxy amino acids in CM and CR carbonaceous chondrites
Meteoritics & Planetary Science, May 2021
56, 5, 1005, 1023
[Reviewed]
Lead

Toshiki Koga; Hiroshi Naraoka
A new family of extraterrestrial amino acids in the Murchison meteorite
SCIENTIFIC REPORTS, Apr. 2017
7
[Reviewed]
Lead