Principal Supervisor: Ian Henderson - Institute of Microbiology and Infection
Co-supervisor: David Grainger
PhD project title: Regulation of multi-drug resistance in Klebsiella pneumoniae
University of Registration: University of Birmingham
Klebsiella pneumoniae causes a wide range of infections, including pneumonias, urinary tract infections, bacteremias, and liver abscesses. Historically, K. pneumoniae has caused serious infection primarily in immunocompromised individuals, but the recent emergence and spread of hypervirulent strains have broadened the number of people susceptible to infections to include those who are healthy and immunosufficient. K. pneumoniae strains have become increasingly resistant to antibiotics, rendering infection by these strains very challenging to treat. Four factors (capsule, lipopolysaccharide, fimbriae, and siderophores) have been well studied in models of infection. However, the mechanisms of resistance to antibiotics have not been well studied. Using high density transposon mutagenesis coupled with next generation sequencing (Illuimina) we identified all genes essential for K. pneumoniae viability. In addition, we screened this library of ca. 400,000 individual mutants for genes that were over represented after growth of the library in the presence of several antibiotics. These experiments identified several uncharacterized genes that were required for antibiotic resistance. A number of these genes bear homology to known transcriptional regulators.
In this project you will select one of these genes for further characterisation. The objectives of the project can be shaped by the interests of the student but will loosely follow the follow ambitions
- Determine the regulatory network for the gene of interest using RNAseq to interrogate genes expression in wild-type and mutant cells
- Investigate how the protein encoded by the gene of interest is regulated or how it regulates other genes. This will be done using DNA footprinting assays and in vitro transcription assays. These tools are used routinely in the lab and all of the required materials are already available.
- Explore how the gene of interest shapes multidrug resistance by comparing the MICs of mutants with the wildtype strains. Studying whether loss of the gene confers a fitness cost for the bacterium and has downstream effects on metabolism.
- Infection based studies of mutant organisms will be investigated with kep collaborators at the University of Melbourne
BBSRC Strategic Research Priority: Food security
Techniques that will be undertaken during the project:
- Next generation sequencing
- Molecular biology
- Animal models
Contact: Professor Ian Henderson, University of Birmingham