PhD (supervisor : R. Carballido-López & Nathalie Campo)

  • Dimitri JUILLOT
  • Position : PhD student (Doctoral school SDSV - Structure et Dynamique des Systèmes Vivants)
  • In the Lab Since: 01/01/2018
  • Email : dimitri.juillot[at]inrae.fr
  • Tel : +33 (0)1 34 65 23 01

Project Description:

Since 01/09/2019

I started my PhD in september 2019 and I work on the pneumococcus.
Streptococcus pneumoniae (pneumococcus) is a pathogen responsible for pneumonia, ear infections and meningitis. The control of this bacterium is hampered by its high genetic variability, which depends largely on its ability to modify its genome by natural genetic transformation. Transformation allows bacteria to capture DNA from the environment and integrate it into their chromosomes to acquire new properties. During the development of transformation, the pneumococcus synthesizes a protein, ComM, which temporarily blocks cell multiplication. The aim of this project is to understand the mechanism of action of ComM and its effect on division apparatus. The strategy is based on the use of super-resolution microscopy techniques and in particular internal total reflection fluorescence microscopy (TIRF) and structured illuminated microscopy (SIM).

01/01/2018 - 31/08/2019

I am working on bacterial morphogenesis by using Bacillus subtilis as model.

An important parameter of morphogenesis is the control of the cell diameter. In B. subtilis, the diameter is always very conserved within the same bacterial population. It is independent of culture conditions and is well defined in a given species. Although the mreB and ponA genes could be involved in this phenomenon, it seems obvious that it exists others genetic determinants that define the diameter of B. subtilis.

My work in the ProCeD team is to identify these genetic determinants by performing 2 high-throughput screenings:

  • To identify genes (from B. subtilis and heterologous) whose overexpression affects the diameter of B. subtilis, by flow cytometry.
  • Identify diameter mutants within a collection of B. subtilis mutants by high throughput microscopy.

These two screens should lead to the identification of candidate genes, affecting the bacterial diameter and whose study would allow a better understanding how the size is defined in B. subtilis. The study of morphology and cell wall biosynthesis makes sense in the field of public health, with the development of future antimicrobial strategies.


Curriculum Vitae:

2017-2018 | Master 2 – Fundamental microbiology (Paris Saclay university)          
2016-2017 | Master 1 – Life sciences and health, Microbiology (Paris Saclay university)

Modification date: 14 September 2023 | Publication date: 13 September 2018 | By: Cyrille Billaudeau