Understanding the function of Membrane-integral pyrophosphatases.

Lead Research Organisation: University of Leeds
Department Name: School of Biomedical Sciences

Abstract

Background:
Membrane-integral pyrophosphatases (mPPases) are ion pumps that couple the hydrolysis of pyrophosphate to the pumping of Na+ and/or H+ across a membrane. mPPases occur in plants, parasites and (archae)bacteria but despite recent advances in the structural data about mPPases, their mechanism of action remains elusive.

Objectives:
We propose to use a multi-disciplinary approach to:
1. Examine the conformational dynamics of mPPases in membrane environments and identify the molecular details of different states of mPPases that are not available using conventional structural techniques.
2. Based on the structural data from 1, identify highly specific molecules that target mPPases using computer-aided drug design.
3. Use biophysical and molecular biology techniques to refine/validate our computational models/hypotheses.

Novelty:
Whilst the recent structural data about mPPases gave new insights into their function, these structures are static and do not contain a membrane environment. In silico approaches will enable us to examine the dynamics of mPPases in a membrane environment providing new knowledge about the ion permeation mechanism of these proteins. Importantly, they are potential drug targets as mPPases occur in e.g. Plasmodium falciparum (malaria) and Trypanosoma spp (Nagana, sleeping sickness), but not in humans. Our approach will also enable us to develop molecules that target novel states of the enzymes.

Timeliness:
This project is very timely as it combines the advances in computers and computational biophysics/drug design with the recent increase in the available 3D structures of mPPases.

Experimental approach:
The student will combine molecular simulations, modelling, computer-aided drug design and lab-based functional studies. Molecular simulations and modelling and computer-aided drug design will provide predictions about the dynamics on mPPases in a membrane environment and how this may be altered by specific molecules. These will be evaluated/refined experimentally, using biophysical methods.

This project aims to understand the mechanistic details of mPPAses at the molecular level and to identify new molecules that target mPPases. mPPases are essential under low-energy stress in both protozoan parasites e.g. Trypanosoma spp (sleeping sickness), Toxoplasma gondii (infecting up to 90% of pigs), Plasmodium falciparum (malaria) and some bacteria. These diseases have a major impact on food security and human health and thus this project is also aligned to the Agricultural and Food security priority area.

Publications

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Studentship Projects

Project Reference Relationship Related To Start End Student Name
BB/M011151/1 30/09/2015 29/09/2023
2110923 Studentship BB/M011151/1 30/09/2018 28/02/2023 Alexandra Holmes