17.04.2026
An international team led by scientists from the Faculty of Science of the University of Ostrava and the Biological Center of the Academy of Sciences of the Czech Republic has described in detail how bacteria became a permanent part of the host cell during evolution. The research sheds light on one of the key processes that led to the emergence of complex cells in plants, animals and humans, and may also help in the study of related parasites that cause, for example, sleeping sickness.
A team of scientists from the Czech Republic, Germany and the UK focused on the protozoan Angomonas deanei. This single-celled organism, related to parasites that cause tropical diseases, is unique in that it permanently hosts a single bacterium inside it . Most people think of bacteria as the cause of disease. But in this case, the bacterium has become an indispensable partner that is existentially dependent on the protozoan.
The bacterium has retained only a limited set of genes throughout evolution and is no longer able to function independently without its host . It is this relationship that has allowed scientists to describe in detail the process of integrating the bacterium into the cell. They achieved this by analyzing thousands of proteins and creating a detailed map of their distribution in the cell.
"We used a special method that allows us to determine the exact distribution of proteins inside the cell. The analysis showed that the host cell specifically directs its own proteins into the bacterium, thus influencing its functioning and division. At the same time, there is an intensive exchange of substances necessary for energy production and other cellular processes between the two cells. Figuratively speaking, the cell gradually adapted the bacterium to its needs," explains team leader Vjačeslav Jurčenko from the Faculty of Science of the University of Ostrava.
A study published in the journal Nature Communications shows that the mechanism observed in this protozoan could have led to the emergence of mitochondria, the energy-producing cells in cells, in the distant past . This step is one of the fundamental moments in the evolution of complex life on Earth. Without them, the cells of plants, animals, including humans, could not function.
"Our research may also have practical implications. A better understanding of metabolic processes and the mechanisms that control them in this protozoan may help reveal new vulnerabilities in related parasites that cause, for example, Chagas disease or leishmaniasis," adds Julius Lukeš from the Institute of Parasitology of the Biological Center of the Academy of Sciences of the Czech Republic.
The study, titled " Subcellular proteomics reveals a blueprint for endosymbiont integration in the trypanosomatid Angomonas deanei, " was included in the Editors' Highlights selection of the prestigious journal Nature Communications , among the approximately fifty most important recently published works in the field of microbiology. The article also attracted significant attention in the professional community, including during a presentation by one of the authors, Michael Hammond , at the international EMBO | EMBL symposium in Heidelberg.
