Structural routes to the analysis and inhibition of cytochrome P450s in pathogenic bacteria.

Abstract

Disease caused by infectious pathogenic agents has been a leading cause of mortality for the entirety of human history. Developing new ways to understand and interfere with the life-cycle of the causative bacteria and viruses is therefore one of the most productive areas of biological research. Building upon the fundamental ideas concerning the causes of infectious disease, this field has facilitated the development of antibiotics and vaccines, as well as effective strategies for limiting transmission and mortality. In spite of this, the Covid-19 pandemic has illustrated the risk that emergent pathogens, as well as more familiar species with newly acquired resistance to common therapies, represent in an increasingly populated world. Cytochromes P450 (P450s) are ubiquitous heme-containing enzymes that catalyse a diverse array of oxidative reactions. By exploiting heme redox chemistry, these proteins perform vital biological functions including the metabolism of carbon sources and hormone biosynthesis in higher organisms. Some pathogenic bacteria contain unique P450s linked to the infectious cycle and their ability to cause disease. Targeting these enzymes may therefore provide a route to new classes of effective antimicrobials to combat these organisms. Cytochromes P450 are also of significant interest in the fields of biocatalysis, chemical, and synthetic biology, and information about the mechanisms underlying substrate recognition can contribute to advances in these areas. The work described in this thesis involves the application of molecular biology, protein biochemistry, biophysics, and structural biology to produce insights into P450s relevant to pathogenesis in Mycobacterium tuberculosis and Staphylococcus sp. Chiefly, this involved analysis of the binding mode and structure-activity relationships (SAR) for putative inhibitors of relevant cytochromes P450, culminating in the development of cell-active inhibitors targeting CYP125A1 and CYP142A1 ( referred to as CYP125, CYP142 hereafter) from Mycobacterium tuberculosis. It is also hoped that the structural information on the diverse enzyme-ligand complexes may contribute towards future predictive computational approaches for the development of specific small-molecule drugs against challenging targets including cytochromes P450.

Date of Award	29 Mar 2023
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Andrew Munro (Co Supervisor) & David Leys (Main Supervisor)