Revolutionizing biology education: Scientists film ‘giant’ mimivirus in action

The COVID-19 pandemic led to heightened public interest in learning about viruses and how they can cause diseases. There has been a lot of focus on communicating virology concepts to the general public in order to increase awareness about the spread and prevention of viral diseases.

When it comes to teaching biology, however, how do we explain microscopic processes like viral infections to students in the classroom?

In modern science education, seeing is believing—educators are now attempting to capture the attention of students by using eye-catching visuals and videos, instead of just relying on diagrams in a textbook. In the case of viruses, however, one major issue arises. Viruses typically cannot be seen under the familiar ‘light microscope’ available in school and university classrooms, requiring highly specialized and expensive equipment for visualization.

Now, in a study published in the Journal of Microbiology & Biology Education on November 8, 2024, a team led by Professor Masaharu Takemura at the Tokyo University of Science has successfully captured the viral infection process under a light microscope, creating a stunning video showcasing their results. The key to this process was a unique ‘giant’ virus known as Mimivirus. This research was co-authored by Ms. Kanako Morioka and Ms. Ayumi Fujieda at Tokyo’s Yone Production Co., Tokyo, Japan.

Mimivirus has a much larger particle size than most viruses and can actually be seen under a light microscope, making it an ideal candidate for use as an educational tool. The researchers sought to visualize how the Mimivirus infects a microbe called Acanthamoeba. It is difficult to visualize amoebae under a microscope since they are constantly moving in a liquid medium; therefore, they used a modified growth medium containing a jelly-like substance called agar. This growth medium also contained viruses which infected the amoebae, and after infection, the Acanthamoeba cells moving under the agarose gel gradually slowed down.

The researchers were able to film individual cells as they were infected; indeed, we can observe all the steps of the viral infection process in their footage. While healthy Acanthamoeba cells are initially moving around, they gradually slow down and come to a stop following Mimivirus infection. As the amoeba cells stopped moving, the researchers observed the development of a ‘virion factory’ inside the amoeba cell, which produced more ‘virions’ or viral particles. The infected cell ultimately dies as its membrane ruptures.  

Prof. Takemura highlights the study’s innovation, saying, “For the first time in the world, we have succeeded in continuously visualizing the events that are believed to occur in viral infection over a long period of time—such as the proliferation of the virus, its release from cells, and the death of cells during the process.”

The film showing how a single Acanthamoeba cell is infected by Mimivirus was then screened in a biology classroom at the Tokyo University of Science and garnered positive reactions. The researchers observed that the movie influenced the perception of some students regarding viruses and seems to have shifted their views towards more scientific and biological perspectives.

This study also ensures that there is no violation of biological safety guidelines since the Acanthamoeba cells and viruses are grown in an appropriately equipped laboratory. The students in the classroom do not actually handle any of the equipment; the focus is only on screening the filmed video in a classroom setting.

Prof. Takemura is confident that this film will be a valuable tool for teaching biology, explaining that, “It enhances students' understanding of virus proliferation mechanisms and highlights the biological significance of viruses, their impact on host cell fate, and their role in ecosystems.”

Until now, viruses have remained hidden in the shadows, visible only through advanced technology—but this groundbreaking footage changes everything. We are sure that this one-of-a-kind footage will be invaluable to virology and science education experts around the world!

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Reference                     

Title of original paper: Visualization of giant Mimivirus in a movie for biology classrooms

Journal: Journal of Microbiology & Biology Education

DOI:       10.1128/jmbe.00138-24

About The Tokyo University of Science

Tokyo University of Science (TUS) is a well-known and respected university, and the largest science-specialized private research university in Japan, with four campuses in central Tokyo and its suburbs and in Hokkaido. Established in 1881, the university has continually contributed to Japan's development in science through inculcating the love for science in researchers, technicians, and educators.

With a mission of “Creating science and technology for the harmonious development of nature, human beings, and society," TUS has undertaken a wide range of research from basic to applied science. TUS has embraced a multidisciplinary approach to research and undertaken intensive study in some of today's most vital fields. TUS is a meritocracy where the best in science is recognized and nurtured. It is the only private university in Japan that has produced a Nobel Prize winner and the only private university in Asia to produce Nobel Prize winners within the natural sciences field.

Website: https://www.tus.ac.jp/en/mediarelations/

About Professor Masaharu Takemura from Tokyo University of Science

Dr. Masaharu Takemura is a Professor in the Department of Mathematics and Science Education, Graduate School of Science at the Tokyo University of Science. His research interests include giant virus biology, viral eukaryogenesis, and virus education. Over his career, he has published more than 120 papers, amassing over 2,400 citations for his work. His research goal is to elucidate the evolution of giant viruses and eukaryotes and develop teaching materials for virus education.

Funding information

This research was partially supported by the JSPS/KAKENHI grant number 20H03078 to M.T.