Integrative Experimental And Computational Study on the Binding of Potential
Modulators with Glucokinase and Trypanosoma cruzi Cysteine Synthase for Drug Discovery

Abstract

Type 2 diabetes mellitus (T2DM) affects a large portion of the population today and
presents a significant global health concern due to its prevalence. It is estimated to
impact more than 450 million people worldwide, with an expected continual increase.
T2DM is characterised by defective insulin secretion, causing adverse effects including
polydipsia, dysuria, fatigue and blurred vision amongst others. Due to its crucial role in
the catalysis of glucose into glucose-6-phosphate (G6P), glucokinase (GK) is being
actively researched in relation to T2DM and diseases linked to it. GK was also the main
focus of this project, and a series of experimental and computational experiments were
performed to study its activity. The main aim was to crystallise GK with an array of
potential inhibitors, confirming their binding and comparing the results with molecular
docking experiments performed on GOLD. GOLD is a widely recognised molecular
docking software specialising in the prediction of protein-ligand binding. Crystals of GK
were not obtained, however, comparison of binding assays and molecular docking
experiments yielded interesting results, highlighting the conformational complexity of
the protein.
In addition to the study of GK, a second potential drug target Trypanosoma cruzi cysteine
synthase (TcCS) was studied in relation to Chagas disease, a neglected tropical disease
(NTD). The current treatments for Chagas disease are causative of many adverse effects
and are not always effective. Gaining more knowledge and identifying potential drugs for
the protein may be very beneficial. Here, TcCS was successfully expressed, purified and
extensive co-crystallisation experiments with selected compounds resulted in several
protein crystals being obtained. Tested compounds were part of an ensemble of
compounds created during a drug-discovery campaign, that included fragment-based
experiments and investigated a selection of inhibitors from bacterial homologues.
Binding assays with these compounds were performed in parallel to help support X-ray
crystallography experiments. Overall, the results contributed to the drug discovery
campaign and will be utilised in biological studies in the future.