Title: Genome evolution and pathogenicity in intracellular bacteria

Summary:

The Rickettsiales are a group of intracellular bacteria, which include the most successful parasites on the planet. Many Rickettsiales infect arthropods, but their hosts also include protozoa, algae, plants, and vertebrates, and the group includes the causal agents of acute human diseases, such as typhus and Rocky Mountain spotted fever. These bacteria have adapted to their hosts in a huge variety of ways, encompassing both mutualistic and parasitic interactions, and including remarkable reproductive manipulations, such male-killing and feminisation. The adaptive diversity of the group is reflected in their highly dynamic genome evolution, with very high rates of gene gain, loss and rearrangement, and some notable examples of genome degradation and reduction.

Jointly hosted by labs specialising in the cell biology of obligate intracellular bacteria, and evolutionary inference from genomic sequence data, this project will investigate links between pathogen genomics and ecology across the Rickettsiales. We will focus on well-characterised pathways, with known host interactions, such as DAP-type peptidoglycans – components of the bacterial cell wall that are targeted by the host Imd immune signalling pathway. We will then infer the adaptive evolution of these pathways using state-of-the-art methods from population genomics. Results will shed new light on the emergence and persistence of bacterial symbiosis and pathogenicity.

Essential knowledge and skills:

This will be a dry-lab project, involving computational bioinformatics and statistical inference from genome sequences. The only essential requirements are enthusiasm and willingness to learn.

Supervisors:

Jeanne Salje (Pathology/Biochemistry/CIMR): jss53@cam.ac.uk

John Welch (Genetics): jjw23@cam.ac.uk