I24-Microfocus Macromolecular Crystallography
|
Indran
Mathavan
,
Lawrence J.
Liu
,
Sean W.
Robinson
,
Nelly
El-Sakkary
,
Adam Jo J.
Elatico
,
Darwin
Gomez
,
Ricky
Nellas
,
Raymond J.
Owens
,
William
Zuercher
,
Iva
Navratilova
,
Conor R.
Caffrey
,
Konstantinos
Beis
Diamond Proposal Number(s):
[12579]
Open Access
Abstract: Schistosomiasis is a neglected tropical disease caused by parasitic flatworms. Current treatment relies on just one partially effective drug, praziquantel (PZQ). Schistosoma mansoni Venus Kinase Receptors 1 and 2 (SmVKR1 and SmVKR2) are important for parasite growth and egg production, and are potential targets for combating schistosomiasis. VKRs consist of an extracellular Venus Flytrap Module (VFTM) linked via a transmembrane helix to a kinase domain. Here, we initiated a drug discovery effort to inhibit the activity of the SmVKR2 kinase domain (SmVKR2KD) by screening the GSK published kinase inhibitor set 2 (PKIS2). We identified several inhibitors, of which four were able to inhibit its enzymatic activity and induced phenotypic changes in ex vivoS. mansoni. Our crystal structure of the SmVKR2KD displays an active-like state that sheds light on the activation process of VKRs. Our data provide a basis for the further exploration of SmVKR2 as a possible drug target.
|
Oct 2022
|
|
I03-Macromolecular Crystallography
I04-1-Macromolecular Crystallography (fixed wavelength)
I04-Macromolecular Crystallography
|
Jurgen
Brem
,
Tharindi
Panduwawala
,
Jon Ulf
Hansen
,
Joanne
Hewitt
,
Edgars
Liepins
,
Pawel
Donets
,
Laura
Espina
,
Alistair J. M.
Farley
,
Kirill
Shubin
,
Gonzalo Gomez
Campillos
,
Paula
Kiuru
,
Shifali
Shishodia
,
Daniel
Krahn
,
Robert K.
Leśniak
,
Juliane
Schmidt
,
Karina
Calvopina
,
María-Carmen
Turrientes
,
Madeline E.
Kavanagh
,
Dmitrijs
Lubriks
,
Philip
Hinchliffe
,
Gareth W.
Langley
,
Ali F.
Aboklaish
,
Anders
Eneroth
,
Maria
Backlund
,
Andrei G.
Baran
,
Elisabet I.
Nielsen
,
Michael
Speake
,
Janis
Kuka
,
John
Robinson
,
Solveiga
Grinberga
,
Lindsay
Robinson
,
Michael A.
Mcdonough
,
Anna M.
Rydzik
,
Thomas M.
Leissing
,
Juan Carlos
Jimenez-Castellanos
,
Matthew B.
Avison
,
Solange
Da Silva Pinto
,
Andrew D.
Pannifer
,
Marina
Martjuga
,
Emma
Widlake
,
Martins
Priede
,
Iva
Hopkins Navratilova
,
Marek
Gniadkowski
,
Anna Karin
Belfrage
,
Peter
Brandt
,
Jari
Yli-Kauhaluoma
,
Eric
Bacque
,
Malcolm G. P.
Page
,
Fredrik
Björkling
,
Jonathan M.
Tyrrell
,
James
Spencer
,
Pauline A.
Lang
,
Pawel
Baranczewski
,
Rafael
Cantón
,
Stuart P.
Mcelroy
,
Philip S.
Jones
,
Fernando
Baquero
,
Edgars
Suna
,
Angus
Morrison
,
Timothy R.
Walsh
,
Christopher J.
Schofield
Open Access
Abstract: Carbapenems are vital antibiotics, but their efficacy is increasingly compromised by metallo-β-lactamases (MBLs). Here we report the discovery and optimization of potent broad-spectrum MBL inhibitors. A high-throughput screen for NDM-1 inhibitors identified indole-2-carboxylates (InCs) as potential β-lactamase stable β-lactam mimics. Subsequent structure–activity relationship studies revealed InCs as a new class of potent MBL inhibitor, active against all MBL classes of major clinical relevance. Crystallographic studies revealed a binding mode of the InCs to MBLs that, in some regards, mimics that predicted for intact carbapenems, including with respect to maintenance of the Zn(II)-bound hydroxyl, and in other regards mimics binding observed in MBL–carbapenem product complexes. InCs restore carbapenem activity against multiple drug-resistant Gram-negative bacteria and have a low frequency of resistance. InCs also have a good in vivo safety profile, and when combined with meropenem show a strong in vivo efficacy in peritonitis and thigh mouse infection models.
|
Dec 2021
|
|
I04-1-Macromolecular Crystallography (fixed wavelength)
I24-Microfocus Macromolecular Crystallography
|
Martin A.
Redhead
,
C. David
Owen
,
Lennart
Brewitz
,
Amelia H.
Collette
,
Petra
Lukacik
,
Claire
Strain-Damerell
,
Sean W.
Robinson
,
Patrick M.
Collins
,
Philipp
Schäfer
,
Mark
Swindells
,
Chris J.
Radoux
,
Iva Navratilova
Hopkins
,
Daren
Fearon
,
Alice
Douangamath
,
Frank
Von Delft
,
Tika R.
Malla
,
Laura
Vangeel
,
Thomas
Vercruysse
,
Jan
Thibaut
,
Pieter
Leyssen
,
Tu-Trinh
Nguyen
,
Mitchell
Hull
,
Anthony
Tumber
,
David J.
Hallett
,
Christopher J.
Schofield
,
David I.
Stuart
,
Andrew L.
Hopkins
,
Martin A.
Walsh
Open Access
Abstract: Effective agents to treat coronavirus infection are urgently required, not only to treat COVID-19, but to prepare for future outbreaks. Repurposed anti-virals such as remdesivir and human anti-inflammatories such as barcitinib have received emergency approval but their overall benefits remain unclear. Vaccines are the most promising prospect for COVID-19, but will need to be redeveloped for any future coronavirus outbreak. Protecting against future outbreaks requires the identification of targets that are conserved between coronavirus strains and amenable to drug discovery. Two such targets are the main protease (Mpro) and the papain-like protease (PLpro) which are essential for the coronavirus replication cycle. We describe the discovery of two non-antiviral therapeutic agents, the caspase-1 inhibitor SDZ 224015 and Tarloxotinib that target Mpro and PLpro, respectively. These were identified through extensive experimental screens of the drug repurposing ReFRAME library of 12,000 therapeutic agents. The caspase-1 inhibitor SDZ 224015, was found to be a potent irreversible inhibitor of Mpro (IC50 30 nM) while Tarloxotinib, a clinical stage epidermal growth factor receptor inhibitor, is a sub micromolar inhibitor of PLpro (IC50 300 nM, Ki 200 nM) and is the first reported PLpro inhibitor with drug-like properties. SDZ 224015 and Tarloxotinib have both undergone safety evaluation in humans and hence are candidates for COVID-19 clinical evaluation.
|
Jun 2021
|
|
I03-Macromolecular Crystallography
|
Diamond Proposal Number(s):
[15433]
Open Access
Abstract: Kinases represent one of the most intensively pursued groups of targets in modern-day drug discovery. Often it is desirable to achieve selective inhibition of the kinase of interest over the remaining ∼500 kinases in the human kinome. This is especially true when inhibitors are intended to be used to study the biology of the target of interest. We present a pipeline of open-source software that analyzes public domain data to repurpose compounds that have been used in previous kinase inhibitor development projects. We define the dual-specificity tyrosine-regulated kinase 1A (DYRK1A) as the kinase of interest, and by addition of a single methyl group to the chosen starting point we remove glycogen synthase kinase β (GSK3β) and cyclin-dependent kinase (CDK) inhibition. Thus, in an efficient manner we repurpose a GSK3β/CDK chemotype to deliver 8b, a highly selective DYRK1A inhibitor.
|
Aug 2020
|
|
I04-Macromolecular Crystallography
|
Samuel T.
Cahill
,
Jonathan M.
Tyrrell
,
Iva
Hopkins Navratilova
,
Karina
Calvopina
,
Sean W.
Robinson
,
Christopher T.
Lohans
,
Michael A.
Mcdonough
,
Ricky
Cain
,
Colin W. G.
Fishwick
,
Matthew B.
Avison
,
Timothy R.
Walsh
,
Christopher J.
Schofield
,
Jurgen
Brem
Abstract: Background: The β-lactam antibiotics represent the most successful drug class for treatment of bacterial infections. Resistance to them, importantly via production of β-lactamases, which collectively are able to hydrolyse all classes of β-lactams, threatens their continued widespread use. Bicyclic boronates show potential as broad spectrum inhibitors of the mechanistically distinct serine- (SBL) and metallo- (MBL) β-lactamase families. Methods: Using biophysical methods, including crystallographic analysis, we have investigated the binding mode of bicyclic boronates to clinically important β-lactamases. Induction experiments and agar-based MIC screening against MDR-Enterobacteriaceae (n = 132) were used to evaluate induction properties and the in vitro efficacy of a bicyclic boronate in combination with meropenem. Results: Crystallographic analysis of a bicyclic boronate in complex with AmpC from Pseudomonas aeruginosa reveals it binds to form a tetrahedral boronate species. Microbiological studies on the clinical coverage (in combination with meropenem) and induction of β-lactamases by bicyclic boronates further support the promise of such compounds as broad spectrum β-lactamase inhibitors. Conclusions: Together with reported studies on the structural basis of their inhibition of class A, B and D β-lactamases, biophysical studies, including crystallographic analysis, support the proposal that bicyclic boronates mimic tetrahedral intermediates common to SBL and MBL catalysis. General significance: Bicyclic boronates are a new generation of broad spectrum inhibitors of both SBLs and MBLs.
|
Apr 2019
|
|
I04-1-Macromolecular Crystallography (fixed wavelength)
I04-Macromolecular Crystallography
|
Aurélie
Mousnier
,
Andrew S.
Bell
,
Dawid P.
Swieboda
,
Julia
Morales-Sanfrutos
,
Inmaculada
Perez-Dorado
,
James A.
Brannigan
,
Joseph
Newman
,
Markus
Ritzefeld
,
Jennie A.
Hutton
,
Anabel
Guedán
,
Amin S.
Asfor
,
Sean W.
Robinson
,
Iva
Hopkins-Navratilova
,
Anthony J.
Wilkinson
,
Sebastian L.
Johnston
,
Robin J.
Leatherbarrow
,
Tobias J.
Tuthill
,
Roberto
Solari
,
Edward W.
Tate
Diamond Proposal Number(s):
[12579, 7864, 9948]
Abstract: Rhinoviruses (RVs) are the pathogens most often responsible for the common cold, and are a frequent cause of exacerbations in asthma, chronic obstructive pulmonary disease and cystic fibrosis. Here we report the discovery of IMP-1088, a picomolar dual inhibitor of the human N-myristoyltransferases NMT1 and NMT2, and use it to demonstrate that pharmacological inhibition of host-cell N-myristoylation rapidly and completely prevents rhinoviral replication without inducing cytotoxicity. The identification of cooperative binding between weak-binding fragments led to rapid inhibitor optimization through fragment reconstruction, structure-guided fragment linking and conformational control over linker geometry. We show that inhibition of the co-translational myristoylation of a specific virus-encoded protein (VP0) by IMP-1088 potently blocks a key step in viral capsid assembly, to deliver a low nanomolar antiviral activity against multiple RV strains, poliovirus and foot and-mouth disease virus, and protection of cells against virus-induced killing, highlighting the potential of host myristoylation as a drug target in picornaviral infections.
|
May 2018
|
|
I02-Macromolecular Crystallography
|
Diamond Proposal Number(s):
[10121]
Abstract: Fungal β-1,3-glucan glucanosyltransferases are glucan-remodeling enzymes that play important roles in cell wall integrity, and are essential for the viability of pathogenic fungi and yeasts. As such, they are considered possible drug targets, although inhibitors of this class of enzymes have not yet been reported. Herein we report a multidisciplinary approach based on a structure-guided design using a highly conserved transglycosylase from Sacharomyces cerevisiae, that leads to carbohydrate derivatives with high affinity for Aspergillus fumigatus Gel4. We demonstrate by X-ray crystallography that the compounds bind in the active site of Gas2/Gel4 and interact with the catalytic machinery. The topological analysis of noncovalent interactions demonstrates that the combination of a triazole with positively charged aromatic moieties are important for optimal interactions with Gas2/Gel4 through unusual pyridinium cation–π and face-to-face π–π interactions. The lead compound is capable of inhibiting AfGel4 with an IC50 value of 42 μm.
|
Dec 2017
|
|
I03-Macromolecular Crystallography
|
Abstract: The discovery of novel bromodomain inhibitors by fragment screening is complicated by the presence of dimethyl sulfoxide (DMSO), an acetyl-lysine mimetic, that can compromise the detection of low affinity fragments. We demonstrate surface plasmon resonance as a primary fragment screening approach for the discovery of novel bromodomain scaffolds, by describing a protocol to overcome the DMSO interference issue. We describe the discovery of several novel small molecules scaffolds that inhibit the bromodomains PCAF, BRD4, and CREBBP, representing canonical members of three out of the seven subfamilies of bromodomains. High-resolution crystal structures of the complexes of key fragments binding to BRD4(1), CREBBP, and PCAF were determined to provide binding mode data to aid the development of potent and selective inhibitors of PCAF, CREBBP, and BRD4.
|
Dec 2016
|
|
I03-Macromolecular Crystallography
|
Abstract: O-GlcNAcylation is a reversible type of Ser/Thr glycosylation on nucleocytoplasmic proteins in metazoa. Various genetic approaches in several animal models have revealed that O-GlcNAcylation is essential for embryogenesis. However, the dynamic changes in global O-GlcNAcylationand the underlying mechanistic biology linking them to embryonic development is not understood. One of the limiting factors towards characterizing changes in O-GlcNAcylation has been the limited specificity of currently available tools to detect this modification. In this study, harnessing the unusual properties of an O-GlcNAcase mutant that binds O-GlcNAc sites with nanomolar affinity, we uncoverchanges in protein O-GlcNAcylation as a function of Drosophila development.
|
Aug 2015
|
|
I24-Microfocus Macromolecular Crystallography
|
Michael D.
Urbaniak
,
Iain T.
Collie
,
Wenxia
Fang
,
Tonia
Aristotelous
,
Susanne
Eskilsson
,
Olawale G.
Raimi
,
Justin
Harrison
,
Iva Hopkins
Navratilova
,
Julie A.
Frearson
,
Daan M. F.
Van Aalten
,
Michael A. J.
Ferguson
Open Access
Abstract: Bacteriocin; P aeruginosa.; pyocin S2; pyocin AP41; immunity protein Uridine diphosphate N-acetylglucosamine pyrophosphorylase (UAP) catalyzes the final reaction in the biosynthesis of UDP-GlcNAc, an essential metabolite in many organisms including Trypanosoma brucei, the etiological agent of Human African Trypanosomiasis. High-throughput screening of recombinant T. brucei UAP identified a UTP-competitive inhibitor with selectivity over the human counterpart despite the high level of conservation of active site residues. Biophysical characterization of the UAP enzyme kinetics revealed that the human and trypanosome enzymes both display a strictly ordered bi−bi mechanism, but with the order of substrate binding reversed. Structural characterization of the T. brucei UAP−inhibitor complex revealed that the inhibitor binds at an allosteric site absent in the human homologue that prevents the conformational rearrangement required to bind UTP.
The identification of a selective inhibitory allosteric binding site in the parasite enzyme has therapeutic potential.
|
Sep 2013
|
|
