MICROSCOPE-BL3

The aim of this proposal is the acquisition of an inverted microscope,
equipped with a microfluidic system for the culture of individual bacteria or
the culture of mammalian cells.
The main biological question of this project is the growth of the bacterial
pathogen Brucella abortus, in the presence of one or several stress agents,
or inside host cells. The proposed equipment should allow the time-lapse
follow up of bacterial at the single cell level, to quantify their growth and
their intracellular trafficking. The growth and the initiation of chromosomes
replication will be followed thanks to Brucella abortus strains producing
fluorescent reporters, that have been constructed in our laboratory. We will
thus be able to study the bacterial response in terms of cell cycle
progression, in the presence of different stress conditions. These analyses
will also attempt to highlight the heterogeneity of the fate of intracellular
bacteria, our preliminary data indicating that a fraction of the bacteria do not
grow inside host cells. This could be related to bacterial persistence,
correlating with the chronic nature of the Brucella abortus infection.
The proposed equipment will be open to other research topics, such as the
analysis of the response of the bacterial model Caulobacter crescentus to
toxic metals like copper.