Combatting multi-drug resistant bacteria

Antimicrobial resistance (AMR) is a major crisis for human medicine. Globally, untreatable bacterial infections are increasing, leaving limited treatment options. Gram-negative Enterobacteriaceae e.g. Klebsiella pneumoniae with carbapenem resistance are classified as critical priorities by the WHO. An important characteristic of bacteria is their ability to share genetic information, including AMR genes, via mobile-genetic elements such as plasmids. Plasmids can share multiple genes producing resistance to clinically important antibiotics such as b-lactams, (including carbapenems), and even drugs-of-last-resort such as colistin. In addition, plasmids can carry genes for increased virulence. Evidence indicates clinically-relevant AMR plasmids persist even in the absence of antibiotics (e.g. Buckner et al, 2018). Pathogens with plasmids carrying AMR genes are responsible for some of the most difficult to treat and often multi-drug resistant infections.

The Buckner lab have developed a flow-cytometry and microscopy-based assay to monitor plasmid transmission and persistence in bacterial populations, using clinically relevant multi-drug resistant bacteria. The assay includes K. pneumoniae with AMR plasmids tagged with the gfp gene, in conjunction with recipient bacteria labelled with the mcherry gene, to measure plasmid dynamics (conjugation and persistence) (Buckner et al, mBio, 2020). This system has been optimised for screening for drugs and compounds that inhibit the conjugation and/or persistence of AMR plasmids (termed “anti-plasmid compounds”) (e.g. Alav et al. 2024a, Alav et al. 2024b).

This project aims to assess the efficacy and mechanism of action of novel anti-plasmid compounds using a panel of multi-drug resistant Klebsiella pneumoniae clinical isolates. This project will involve the following specific objectives:

1)    Long read sequence and annotate the genomes (including plasmids) of clinical isolates.

2)    Phenotypically analysed conjugative potential of clinical isolates

3)    Determine the range of activity of a library of anti-plasmid compounds

4)    Determine the mechanism of action of anti-plasmid compounds

The techniques used in this project include: Long and short read sequencing, bioinformatics, cloning, plasmid conjugation assays (including but not limited to flow cytometry, differential plating), high-throughput drug screening, antimicrobial susceptibility testing, plasmid stability assays, bacterial phenotypic assays (which may include microscopy, RNA sequencing, biochemical analysis, metabolomics).

Person Specification 

Applicants should have a strong background in Microbiology. They should have a commitment to research in immunology, infection, or biochemistry and hold or realistically expect to obtain at least an Upper Second Class Honours Degree or equivalent.