Synthesis of tools for studying the AmpG pore protein involved in antibiotic resistance
department or school: Science, Faculty of
department or school: Chemistry, Department of
data provider: DSpace
degree campus: UBCV
creator: Vacariu, Condurache
issued: 2024-07-22T21:22:35Z
issued: 2024
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: The periplasmic pore protein AmpG, normally responsible for the transport of peptidoglycan fragments from the periplasm to the cytosol of Gram-negative bacteria, has been implicated in the biochemical pathway for AmpC β-lactamase induction. Consequently, strains of pathogenic Gram-negative bacteria such as Pseudomonas aeruginosa have developed resistance to a wide swath of antibiotics bearing the β-lactam functional group (i.e. antibiotics of the penicillin family). One approach to combat this growing threat would be to prevent the induction of AmpC’s in the target organisms before treating them with antibiotics. AmpG is ubiquitous and highly conserved among Gram-negative bacteria; it therefore serves as a potential drug target. Unfortunately, relatively little is known about AmpG’s structure and substrate preference owing to the difficulty in both the expression and isolation of this integral membrane protein. Working in collaboration with the Strynadka lab at UBC, who are experts in membrane protein characterization, we sought to elucidate the structure of AmpG – in particular, its glycopeptide substrates’ recognition site – in the hopes of eventually designing an irreversible inhibitor specific to it. Towards this end, we chemically synthesized multimilligram quantities of various putative AmpG substrates – including a large glycopeptide bearing the unnatural meso-oxa-diaminopimelic acid – for our collaborators to test against recombinant AmpG that was purified and reconstituted either in detergent micelles or in peptide nanodiscs. The affinities of our putative substrates towards AmpG are currently being evaluated via isothermal calorimetry. In addition, we synthesized a dendron-based putative inhibitor of AmpG in which a bulky “plug” is attached to an AmpG substrate via a flexible linker: this putative inhibitor will be tested using a lipid planar bilayer or fluorescence assay experiment. Finally, we synthesized a putative AmpG substrate with a compact photoaff…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/88674
note: Synthesis of Tools for Studying the AmpG Pore Protein involved in Antibiotic Resistance by Condurache Vacariu A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES (Chemistry) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) July 2024 © Condurache Vacariu, 2024 ii The following individuals certify that they have read, and recommend to the Faculty of Graduate and Postdoctoral Studies for acceptance, the dissertation entitled: Synthesis of Tools for Studying the AmpG Pore Protein involved in Antibiotic Resistance submitted by Condurache Vacariu in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry Examining Committee: Martin Tanner, Professor, Chemistry, UBC Supervisor Marco Ciufolini, Professor, Chemistry, UBC Supervisory Committee Member Gregory Dake, Professor, Chemistry, UBC University Examiner Russ Algar, Professor, Chemistry, UBC University Examiner Additional Supervisory Committee Members: Raymond Andersen, Professor, Chemistry, UBC Supervisory Committee Member Hongbin Li, Professor, Chemistry, UBC Supervisory Committee Member iii Abstract The periplasmic pore protein AmpG, normally responsible for the transport of peptidoglycan fragments from the periplasm to the cytosol of Gram-negative bacteria, has been implicated in the biochemical pathway for AmpC β-lactamase induction. Consequently, strains of pathogenic Gram-negative bacteria such as Pseudomonas aeruginosa have developed resistance to a wide swath of antibiotics bearing the β-lactam functional group (i.e. antibiotics of the penicillin family). One approach to combat this growing threat would be to prevent the induction of AmpC’s in the target organisms before treating them with antibiotics. AmpG is ubiquitous and highly conserved among Gram-negative bacteria; it therefore serves as a potential drug target. Unfortunately, relatively little is known about AmpG’s structur…
has type: Thesis/Dissertation
date issued: 2024-11
is shown at: 10.14288/1.0444190
language: eng
degree discipline: Chemistry
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
contributor: Tanner, Martin E.
type: Text
identifier URI: http://hdl.handle.net/2429/88674