Copper homeostasis regulation during different development stages of three alpha-proteobacteria Renewal

Intracellular copper is essential at low concentration, but becomes highly
toxic when present in excess. Therefore, there is a strong need for an
organism to finely tune its copper homeostasis. The goals of this research
project are split in two parts. The first one aims to identify the precise
functions of the PcoA and PcoB proteins, which are involved in copper
homeostasis in the aquatic α-proteobacterium Caulobacter crescentus.
These functions will be studied by various biochemical and cellular biology
techniques.
The second part of this project will focus on extending and
extrapolating the investigation on the regulation of copper homeostasis to
two others α-proteobacteria : the animal pathogen Brucella melitensis and
the plants symbiote Sinorhizobium meliloti. Similarly to C. crescentus, these
two bacterial species display various cellular forms that can adapt to diverse
environments. B. melitensis and S. meliloti are both able to live outside their
host, and are known to modulate their gene expression upon infection.
Therefore, we will try to assess the ability of the different development
stages of B. melitensis and S. meliloti to adapt to a copper stress. PcoA
being conserved in these two bacteria, we will evaluate the role of this
protein in B. melitensis and S. meliloti copper homeostasis.