Structural studies to inform antimicrobial drug discovery and the basis of immunity against T6 effectors

Abstract

Work presented in this thesis is in two parts.
Part one: The X-ray crystal structures of potential antimicrobial drug targets.
The protein IspF (2C-methyl-D-erythritol-2,4-cyclodiphosphate synthase, EC: 4.6.1.12) from two pathogens (Burkholderia cenocepacia and Plasmodium falciparum) has been investigated. IspF is an enzyme of isoprenoid-precursor biosynthesis and is considered to be a potential drug target. The results of structural and fragment-screening efforts presented here inform early stage drug discovery efforts.
The structure of the PabC protein (4-amino-4-deoxychorismate lyase, EC: 4.1.3.38) from the Gram-negative pathogen Pseudomonas aeruginosa was also determined. PabC is involved in the production of para-aminobenzoic acid on the path to folate. Comparisons with previously solved PabC structures identified a spatially conserved tyrosine residue in the active site and suggest that a re-evaluation of a published mechanism is warranted.
Part two: Immunity proteins in the Gram-negative Type VI secretion system.
The X-ray crystal structures of the proteins Rap1a and Rap2a from Serratia marcescens, inhibitors of the peptidoglycan amidase toxins secreted by some Gram-negative bacteria employing the Type VI secretion pathway, were determined by molecular replacement and analysed.

Date of Award	2013
Original language	English
Awarding Institution	University of Dundee
Sponsors	Biotechnology and Biological Sciences Research Council
Supervisor	Bill Hunter (Supervisor)