24/07/2023 .
Emmanuelle Bille was granted ANR PRME for her project on N. meningitidis and filamentous phage biology. The Neisseria group was also granted ANR PRC in collaboration with Sandrine Bourdoulous.
Partnership Between Filamentous Phages and Type IV Pili in virulent meningococci (PaPi)
The overall objective of our project is to decipher the partnership between the MDA filamentous bacteriophage and N. meningitidis, which benefits both the bacteriophage and virulence ofmeningococci. We will follow two main objectives: (1) to identify how the MDAΦ has evolved to hijack type IV pili to enter bacterial cell and be secreted without lysis; (2) to characterize how MDAΦ alters meningococcal physiology to its advantage and how it affects virulence.
Our hypothesis is that the coevolution of MDAΦ with N. meningitidis, a bacterium subject to high phase variation and antigenic variation, led MDAΦ to adapt its life cycle to the specificities of its host and thus to acquire characteristics different from those of other filamentous phages such as Ff or CTXΦ. Hence, MDAΦ has evolved an original strategy to interact with meningococcal T4P and to be secreted. In addition, the association of MDAΦ with hypervirulent meningococcal lineages suggests that N. meningitidis benefits from phage infection in a mutualistic relationship.