Exploring the interactions between host and bacterial kinase signalling networks

Pathogenic microorganisms are rapidly developing resistance to our current arsenal of antimicrobial therapies at a rate that vastly outpaces our ability to create new treatments. Infections related to antibiotic resistant bacteria globally rank amongst the leading causes of death, with recent projections estimating that they will surpass deaths by cancer by 2050. Consequently, antimicrobial resistance in pathogenic organisms is recognised to be one of the top 10 health problems facing humanity, according to the WHO. As such, there is an urgent need for alternative chemotherapeutic intervention strategies to counteract the challenges posed by multi-drug resistant (MDR) bacteria.

Bacterial responses to extracellular stimuli (including the decision to transition to a more virulent phenotype) are largely governed by two-component signalling systems (TCSs), involving phosphoryl-transfer from sensor histidine protein kinases to a respective aspartate-containing response regulator. However, advances in meta-genomic sequencing has revealed that ‘eukaryotic-like’ Ser/Thr kinases (eSTKs), which contain structurally homologous catalytic domains to human kinases, are ubiquitous in prokaryotic genomes. Although the functions of these eSTKs are poorly understood, it is clear they are associated with bacterial physiology and pathogenicity. Given the established ‘druggability’ of the protein kinase fold, eSTKs are enticing novel targets for small molecule antimicrobial inhibitors.

This multidisciplinary studentship will focus on biochemical characterisation of eSTKs, initially concentrating on secreted kinases of the opportunistic pathogen Legionella pneumophilia, and will provide training in the areas of biochemistry, molecular/cellular kinase biology and mass-spectrometry-based (phospho)proteomics. In this project, you will isolate secreted bacterial eSTKs using a variety of industry standard protein purification methodologies, and subject them to detailed biochemical characterisation using analytical techniques traditionally used to study human protein kinases, to improve our molecular understanding of these enigmatic signalling molecules. Crucially, the disease profile of L. pneumophilia also involves secretion of functionally diverse virulence effectors, including eSTKs, into the cytoplasm of a host cell. The student will also use LC-MS/MS-based (phospho)proteomic assays, in conjunction with proximity interactome analysis, to decipher host-pathogen interaction networks in mammalian overexpression systems and gain insights into the disease processes that promote intracellular survival of invading L. pneumophilia.

Candidates should be highly motivated, have practical laboratory experience and hold/expect to hold a Masters’ degree or a BSc at a first of upper 2:1 class in biochemistry/ molecular biology/ microbiology or a related discipline.

Applications (in the form of a CV and covering letter) and other enquiries should be emailed to Dr Dom Byrne at bs0u4193@liverpool.ac.uk.