PhD in bacterial cell biology

The Laloux lab is a research group of the de Duve Institute located on the Brussels campus of the University of Louvain (UCLouvain). For more info on the group, please check our website (http://www.lalouxlab.weebly.com; https://www.deduveinstitute.be/bacterial-cell-biology).

Our goal is to uncover how bacterial cells organize their molecular content in space and time to fulfill their fascinating lifecycles. We focus mostly on the model predatory bacterium Bdellovibrio bacteriovorus, which feeds upon other Gram-negative bacteria. During its original cell cycle, this bacterium enters inside the envelope of its prey (e.g. E. coli or other species), which is finely remodeled by the predator to become a stable niche. B. bacteriovorus then digests the cellular content of the prey and grows as a filament which eventually septates in a variable number of daughter cells by a process of non-binary division. The molecular factors that govern the non-canonical biology of B. bacteriovorus, which stands in sharp contrast with the textbook knowledge, are still largely unknown. In our lab, we use bacterial genetics, molecular biology and live quantitative microscopy at high resolution, to unravel the novel mechanisms that control key processes of the outstanding cell cycle of this small predator. In the past years, we have set up image analysis and native fluorescent reporters to visualize cellular processes within the predator, monitor subcellular organization, and follow prey-predator interactions at the single-cell level.

Recently, we have started to focus on another predatory bacterium (B. exovorus) which shares high similarity with B. bacteriovorus but feeds by staying attached to the prey surface. The drastically different feeding strategy and lifecycle between these two closely related predators allow us to further explore bacterial predation at the single-cell and molecular levels, and raise new fascinating biological questions.

We are looking for a highly motivated candidate to pursue an exciting thesis project in our lab, aiming at understanding the predatory action and the unique cell cycle of B. exovorus, at the molecular and cellular levels. Ideally, we would like to start the project no later than the Spring or Summer 2023 (flexible starting date).

Techniques will include (but are not limited to): genetic engineering of predator and prey bacterial species, live epifluorescence microscopy (including microfluidics), quantitative image analysis, molecular cloning, biochemistry, proteomics, measurements of prey-predator interactions, and routine molecular bacteriology techniques.

During the PhD, the candidate is expected to attend national and international scientific meetings and to present their work in the form of posters or oral communications when appropriate. The candidate will also have to contribute to the writing of scientific papers for the publication of their work in peer-reviewed journals.

Related publications from the lab (on B. bacteriovorus):

Kaljevi , J., Saaki, T. N. V., Govers, S. K., Remy, O., Raaphorst, R. van, Lamot, T. & Laloux, G. Chromosome choreography during the non-binary cell cycle of a predatory bacterium. Curr Biol 31, 3707-3720.e5 (2021).

Santin, Y. G., Lamot, T., Kaljevi , J., Raaphorst, R. van & Laloux, G. Modulation of prey size reveals adaptability and robustness in the cell cycle of an intracellular predator. bioRxiv (2022). doi:10.1101/2022.12.18.520956

Remy, O., Lamot, T., Santin, Y., Kaljevi , J., Pierpont, C. de & Laloux, G. An optimized workflow to measure bacterial predation in microplates. Star Protoc 3, 101104 (2022).

Laloux, G. Shedding Light on the Cell Biology of the Predatory Bacterium Bdellovibrio bacteriovorus. Front Microbiol10, 3136 (2020).