Research First !

Thank you for visiting the website of our department.

The Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University is working to analyze

the molecular pathogenesis of infectious diseases and cancer from a new perspective based on sulfur metabolism,

as well as to develop new treatments for these diseases.

What's New?

  • 2024/07/01 [Special Lecture] Prof. Young-Joon Surh of Seoul National University, Korea, gave a special lecture. <link>
  • 2024/06/21 [Publications] Graduate student Ms. Li’s paper has been accepted for publication in International Immunology! This is a joint research with Prof. Ming Xian of Brown University, USA. <link>
  • 2024/04/25 [OB visits] Dr. Akter Molla, an alumnus who now lives in the U.S., visited our laboratory. <link>
  • 2024/04/16 [Publications] Dr. Tomita and Prof. Kawamura of Aichi-Gakuin University presented a paper on the identification of a new species of Helicobacter sp. named higonensis. Profs. Sawa and Tsutsuki also participated as co-authors. <link>
  • 2024/03/26 [Farewell Party] We held a farewell party for Prof. Maeda, Associate Professor in the Virus Research Section. <link>
  • 2024/01/23 [Publications] A paper with Prof. Maeda, Associate Professor in the Virus Research Section, as the first author, was published in Int. J. Mol. Sci. <link>
  • 2024/01/19 [Publications] A Japanese review article with Prof. Tsutsuki, lecturer, as the first author has been published in YAKUGAKU ZASSHI. <link>
  • 2024/01/19 [Publications] A paper with Prof. Ishima of Kyoto Pharmaceutical University was published in Pharmaceuticals. Prof. Sawa also participated as a co-author. <link>
  • 2024/01/18 [Publications] A joint paper with Prof. Min Xiang and colleagues at Brown University, USA, has been published in Redox Biology. Graduate student Ms. Guo and research fellow Dr. Zhang also participated in this project. <link>
  • 2024/01/06 [Publications] A review article with Prof. Tsutsuki, lecturer, as the first author has been published in International Immunology. It is co-authored with Prof. Akaike of Tohoku University. <link>
We're looking for graduate students to work with us on our research!
Please feel free to contact us anytime if you are interested. Please refer to the link (in Japanese) for the entrance examination for the 2023 academic year. <link>


The origin of medical education in Kumamoto is said to be the "Saishunkan Medical Dormitory" established by Shigeken Hosokawa, the lord of the Higo domain, in 1756. Furthermore, Shibasaburo Kitasato, who is known as the father of bacteriology in Japan, studied under a Dutch doctor, Dr. Mansfeldt, as a medical student at the "Kojo Medical School" established by the Kumamoto domain in 1870.

The Department of Microbiology was established in 1907, shortly after the private Kumamoto Medical School, the predecessor of Kumamoto University School of Medicine, was approved as a medical school.

Since the inauguration of the first Professor Hidekazu Nakajima, the following professors have been appointed: the 2nd Professor Toyokichi Ohtahara (Kumamoto Medical College), the 3rd Professor Tokichi Rokutanda (National Kumamoto University School of Medicine), the 4th Professor Yorio Hinuma (National Kumamoto University School of Medicine), the 5th Professor Hiroshi Maeda (moved to National University Corporation), the 6th Professor Takaaki Akaike (Kumamoto University Graduate School of Medicine and Pharmaceutical Sciences, Department of Microbiology; currently Tohoku University), and the current Professor Tomoaki Sawa (Department of Microbiology, Kumamoto University Graduate School of Life Sciences), have taken over the Department of Microbiology and have a history of more than 100 years.

Our department has produced many researchers and educators who have led the field of infectious diseases not only in Japan but also in the world.

Inheriting this illustrious tradition, since 2014, under the leadership of Professor Tomohiro Sawa, we have been conducting research on the molecular pathogenesis of infectious diseases, immunity, and cancer from the new perspective of sulfur metabolism, while at the same time providing undergraduate and graduate education for the development of outstanding human resources.


In our laboratory, we are conducting basic research to understand the mechanisms of infectious diseases caused by bacteria and viruses at the molecular level, and to obtain knowledge that can be applied to effective prevention, diagnosis, and treatment. In particular, we are studying the stress response mechanisms of pathogens and host cells in the field of infection using the latest analytical techniques. We are currently working on the following research projects.


I. Elucidation of Sulfur Metabolism and Antioxidant Defense Mechanism in Bacteria

II. Novel Metallo-β-Lactamase Inhibitors

III. Analysis of The Mechanism of Action of Enterohemorrhagic Escherichia Coli Toxin (SubAB)

IV. Regulation of Innate Inflammation and Infectious Immunity by Reactive Sulfur Species.

Ⅴ.    Elucidation of The Antiviral Effects of Reactive Sulfur Species

VI.   Analysis of the intracellular invasion mechanism of human immunodeficiency virus (HIV-1)

VII. Elucidation of the mechanism of HIV-1 acquisition of drug resistance.

VIII. Effects of Human Endogenous Viruses (HERVs) and HIV-1 on Infection and Replication

Ⅸ. Analysis of the interaction between envelope proteins and receptors of human T-cell leukemia virus (HTLV-1).

Ⅹ. Research on Polymeric Anticancer Agents

Ⅺ.Research on The Spread of Drug-Resistant Bacteria and Its Prevention

VI~IX are projects in Virus Research Section.

Please also see our research projects site.

Recent Publications

  • Li, X., Toyomoto, T.,  Zhang, T., Guo, C., Lindahl, S., Tsutsuki, H., Xian, M., Sawa, T., Supersulfides suppress type-I and II interferon responses by blocking JAK/STAT signaling in macrophages. International Immunology, dxae040, 
  • Tomida, J., Miyoshi-Akiyama, T., Kutsuna, R., Tsutsuki, H., Sawa, T., Cnockaert, M., Vandamme, P., Kawamura, Y., Proposal of Helicobacter higonensis sp. nov. isolated from a human clinical specimen, and emended description of Helicobacter valdiviensis Collado, 2014. Microbiol Immunol. 2024 Apr 10. doi: 10.1111/1348-0421.13127. 
  • Maeda, Y., Toyoda, M.,  Kuwata, T., Terasawa, H., Tokugawa, U., Monde, K., Sawa, T., Ueno, T., Matsushita, S., Differential Ability of Spike Protein of SARS-CoV-2 Variants to Downregulate ACE2. Int. J. Mol. Sci. 2024, 25(2), 1353;
  • Tsutsuki, H., Zhang, T., Akaike, T., Sawa, T., Regulation of innate immune and inflammatory responses by supersulfides. International Immunology, dxad057,

Please also see our publication site.


Members in the Virus Research Section are here.

【Professional Staffs】

Tomohiro Sawa, PhD. (Professor)
Hiroyasu Tsutsuki, PhD. (Lecturer)
Katsuhiko Ono, PhD. (Assistant Professor)

Toshio Kasamatsu, PhD. (Research Associate)

【General Staffs】

Eriko Doi (Technical Assistant)

Azizur Rahman (Technical Assistant)


Toya Toyomoto (D3)

Kei-ichi Yamamoto (D3)

Xiaoyan Li (D3)

Foysal Hossen (D3)

Chunyu Guo (D2)

Heng Zhong (D1)

Rika Fukushima (D1)

Ayaka Uegama (M1)

Tsubasa Saito (Under Graduate, Medical School)

Reona Hayashi (Under Graduate, Medical School)