I am interested in understanding how phytoplankton cells control global carbon (C) and nitrogen (N) cycles. My original background is in marine microbiology research. I focused on environmental microbiology through field observations and culture experiments in the laboratory during my Master’s and Ph.D. studies in Tokyo and realized the importance of N2 fixing cyanobacteria as key players in C and N cycles in the oligotrophic ocean. To understand the mechanism behind C and N budget through N2 fixers, I have been focusing on evaluating the relationship between C and N metabolisms: photosynthesis and N2 fixation in the Czech Republic. Recently I am interested in understanding heterogeneity in metabolisms among cells, and trying to evaluate the heterogeneity by visualization of metabolic processes at a single-cell level.