Bacterial interspecies signaling
Dr. Leanid Laganenka
Research Area
In nature, bacteria coordinate their behavior at the group level based on cell density and community structure through a process known as quorum sensing. Despite the molecular diversity of quorum sensing systems across bacterial species, all rely on the production and detection of small signaling molecules called autoinducers. While most autoinducers facilitate intraspecies communication, only one - autoinducer-2 (AI-2) - is known to be produced by a variety of bacteria, enabling interspecies and potentially even interdomain communication.
Using Klebsiella pneumoniae as a model organism, we aim to understand the principles of interspecies signaling in establishing bacteria-bacteria and bacteria-host interactions, including infection. Specifically, we investigate how AI-2 signaling regulates cell physiology, collective behavior, and host-microbe interactions in this lung pathogen. In particular, we explore how AI-2 signaling mediates interactions between K. pneumoniae and innate immune cells.
We are also interested in how AI-2 signaling in K. pneumoniae influences its ability to persist outside the human host and interact with environmental bacteria.
For these purposes, we utilize a combination of in vitro techniques (including proteomics, flow cytometry, and advanced imaging) and in vivo models (such as a mouse model of gut colonization and pneumonia).
Selected publications
Laganenka, L., Schubert, C., Barthel, M., Nguyen, B., Näf, J., Lobriglio, T., Hardt, W.-D. 2024. Interplay between chemotaxis, quorum sensing, and metabolism regulates Escherichia coli-Salmonella Typhimurium interactions in vivo // bioRxiv. doi: 10.1101/2024.08.19.608533.
Laganenka, L., Lee, J.-W., Malfertheiner, L., Dieterich C., Fuchs L., Piel, J., von Mering, C., Sourjik, V., Hardt, W.-D. 2022. Chemotaxis and autoinducer-2 signalling mediate colonization and co-existence of Escherichia coli strains in the murine gut // Nat Microbiol. 8 (2), 204-217. doi: 10.1038/s41564-022-01286-7.
Laganenka, L., Sander, T., Lagonenko, A., Chen, Y., Link, H., Sourjik, V. 2019. Quorum sensing and metabolic state of the host control lysogeny-lysis switch of bacteriophage T1 // mBio 10:e12884-19. doi: 10.1128/mBio.01884-19.
Laganenka, L., Sourjik, V. 2018. Autoinducer 2-dependent Escherichia coli biofilm formation is enhanced in a dual-species coculture // Appl Environ Microbiol. 84:e02638-17. doi: 10.1128/AEM.02638-17.
Laganenka, L., Colin, R., Sourjik, V. 2016. Chemotaxis towards autoinducer 2 mediates autoaggregation in Escherichia coli // Nat Commun 7. – 12984. doi: 10.1038/ncomms12984.