Project ID CM-HD2026_16

ThemeCM-HD

Co Supervisor 1A Dr Julien Bergeron Faculty of Life Sciences & Medicine, School of Basic & Medical Biosciences, Randall Centre for Cell & Molecular BiophysicsEmail

Co Supervisor 1B Prof Miraz Rahman Faculty of Life Sciences & Medicine, School of Cancer & Pharmaceutical Sciences, Institute of Pharmaceutical ScienceEmail

Cracking Superbugs: Using AI and Cryo-EM to Decode Antibiotic Resistance

(a) Gram-negative bacteria include some of the most severe human pathogens, including Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella, Enterobacteria and more. A common trait between these is the possession of an outer lipidic membrane, which notably protects them from antibiotics. Accordingly, elucidation the molecular details of the formation and maintenance of this outer membrane could pave the way towards the development of new antibiotics.

(b) The student will employ structure-based drug design approaches to develop inhibitors of the machinery involved in OM biogenesis. Following this, they will be trained in the synthesis of such inhibitors, and their chemical characterization. Next, they will gain experience in the biochemical characterization of their interaction with the targeted machinery, and will learn how to determine the structure of these complexes by cryo-EM. Finally, they will have the opportunity to be involved in the efficacy characterization of such chemicals for the treatment of antibiotic-resistant bacterial infection.

(c) The overall aim of this project is to develop and characterize small-molecule inhibitors of the MLA pathway. These will be critical to elucidate its molecular mechanism, and could be used for the treatment of antibiotic-resistant bacterial strains.

(d) The objectives for the PhD are:
– Year 1: Identification of potentially druggable pockets on the structures of the various MLA components (IM complex, OM complex, periplasmic transporter); in-silico screening of potential inhibitors for the most promising pockets; Chemical synthesis of the corresponding molecules
– Year 2: Biochemical and biophysical validation of the compounds’ interaction with their respective binding partners.
– Year 3: Structural elucidation of the MLA components bound to inhibitors, by cryo-EM.
– Year 4: Characterization of the inhibitors’s effect on bacterial growth, and on antibiotic resistance.

(e) The 3-month rotation project focuses on developing small-molecule inhibitors targeting the MLA pathway involved in outer membrane (OM) biogenesis in Gram-negative bacteria, a major contributor to antibiotic resistance. The student will use structure-based drug design to identify druggable pockets and screen for candidate inhibitors, followed by chemical synthesis and characterisation of selected compounds. They will gain experience in biochemical assays to evaluate compound binding and be introduced to cryo-EM methods for structural studies. This project provides interdisciplinary training across computational chemistry, medicinal chemistry, and structural biology, contributing to the development of new strategies to combat antibiotic-resistant bacterial infections.

Representative Publications

1. Wotherspoon, Peter et al. “Structure of the MlaC-MlaD complex reveals molecular basis of periplasmic phospholipid transport.” Nature communications vol. 15,1 6394. 30 Jul. 2024, doi:10.1038/s41467-024-50615-3
2. Mann, Daniel et al. “Structure and lipid dynamics in the maintenance of lipid asymmetry inner membrane complex of A. baumannii.” Communications biology vol. 4,1 817. 29 Jun. 2021, doi:10.1038/s42003-021-02318-4
3. Kamischke, Cassandra et al. “The Acinetobacter baumannii Mla system and glycerophospholipid transport to the outer membrane.” eLife vol. 8 e40171. 14 Jan. 2019, doi:10.7554/eLife.40171

1. Zhu, Y., Hind, C. K., Al-Adhami, T., Wand, M. E., Clifford, M., Sutton, J. M., and Rahman, K. M. (2025) C7-Substituted Quinolines as Potent Inhibitors of AdeG Efflux Pumps in Acinetobacter baumannii, ACS Infectious Diseases. 11, 3, 626–638, https://doi.org/10.1021/acsinfecdis.4c00705
2. Picconi, P., Hind, C. K., Nahar, K. S., Jamshidi, S., Di Maggio, L., Saeed, N., Evans, B., Solomons, J., Wand, M. E., and Sutton, J. M. (2020) New broad-spectrum antibiotics containing a pyrrolobenzodiazepine ring with activity against multidrug-resistant gram-negative bacteria, Journal of Medicinal Chemistry 63, 6941-6958. https://doi.org/10.1021/acs.jmedchem.0c00328
3. Picconi, P., Hind, C., Jamshidi, S., Nahar, K., Clifford, M., Wand, M. E., Sutton, J. M., and Rahman, K. M. (2017) Triaryl benzimidazoles as a new class of antibacterial agents against resistant pathogenic microorganisms, Journal of Medicinal Chemistry 60, 6045-6059. https://doi.org/10.1021/acs.jmedchem.7b00108