Publications by authors named "Jonathan P Hutchinson"

12 Publications

  • Page 1 of 1

Common allotypes of ER aminopeptidase 1 have substrate-dependent and highly variable enzymatic properties.

J Biol Chem 2021 Feb 19:100443. Epub 2021 Feb 19.

National Centre for Scientific Research "Demokritos", Athens 15341, Greece; Laboratory of Biochemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou 157 84, Greece. Electronic address:

Polymorphic variation of immune system proteins can drive variability of individual immune responses. ER aminopeptidase 1 (ERAP1) generates antigenic peptides for presentation by MHC class I molecules. Coding single nucleotide polymorphisms (SNPs) in ERAP1 have been associated with predisposition to inflammatory rheumatic disease and shown to affect functional properties of the enzyme, but the interplay between combinations of these SNPs as they exist in allotypes, has not been thoroughly explored. We used phased genotype data to estimate ERAP1 allotype frequency in 2,504 individuals across five major human populations, generated highly pure recombinant enzymes corresponding to the 10 most common ERAP1 allotypes and systematically characterized their in vitro enzymatic properties. We find that ERAP1 allotypes possess a wide range of enzymatic activities, up to 60-fold, whose ranking is substrate-dependent. Strikingly, allotype 10, previously associated with Behçet's disease, is consistently a low-activity outlier, suggesting that a significant percentage of individuals carry a sub-active ERAP1 gene. Enzymatic analysis revealed that ERAP1 allotypes can differ in both catalytic efficiency and substrate affinity, differences that can change intermediate accumulation in multi-step trimming reactions. Alterations in efficacy of an allosteric inhibitor that targets the regulatory site suggest that allotypic variation influences the communication between the regulatory and the active site. Our work defines the wide landscape of ERAP1 activity in human populations and demonstrates how common allotypes can induce substrate-dependent variability in antigen processing, thus contributing, in synergy with MHC haplotypes, to immune response variability and to predisposition to chronic inflammatory conditions.
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http://dx.doi.org/10.1016/j.jbc.2021.100443DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8024916PMC
February 2021

Development of a small molecule that corrects misfolding and increases secretion of Z α -antitrypsin.

EMBO Mol Med 2021 Mar 29;13(3):e13167. Epub 2021 Jan 29.

GlaxoSmithKline, Stevenage, UK.

Severe α -antitrypsin deficiency results from the Z allele (Glu342Lys) that causes the accumulation of homopolymers of mutant α -antitrypsin within the endoplasmic reticulum of hepatocytes in association with liver disease. We have used a DNA-encoded chemical library to undertake a high-throughput screen to identify small molecules that bind to, and stabilise Z α -antitrypsin. The lead compound blocks Z α -antitrypsin polymerisation in vitro, reduces intracellular polymerisation and increases the secretion of Z α -antitrypsin threefold in an iPSC model of disease. Crystallographic and biophysical analyses demonstrate that GSK716 and related molecules bind to a cryptic binding pocket, negate the local effects of the Z mutation and stabilise the bound state against progression along the polymerisation pathway. Oral dosing of transgenic mice at 100 mg/kg three times a day for 20 days increased the secretion of Z α -antitrypsin into the plasma by sevenfold. There was no observable clearance of hepatic inclusions with respect to controls over the same time period. This study provides proof of principle that "mutation ameliorating" small molecules can block the aberrant polymerisation that underlies Z α -antitrypsin deficiency.
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http://dx.doi.org/10.15252/emmm.202013167DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7933930PMC
March 2021

Targeting the Regulatory Site of ER Aminopeptidase 1 Leads to the Discovery of a Natural Product Modulator of Antigen Presentation.

J Med Chem 2020 03 9;63(6):3348-3358. Epub 2020 Mar 9.

National Centre for Scientific Research "Demokritos", Patriarchou Gregoriou and Neapoleos 27, Agia Paraskevi, Athens 15341, Greece.

ER aminopeptidase 1 (ERAP1) is an intracellular enzyme that generates antigenic peptides and is an emerging target for cancer immunotherapy and the control of autoimmunity. ERAP1 inhibitors described previously target the active site and are limited in selectivity, minimizing their clinical potential. To address this, we targeted the regulatory site of ERAP1 using a high-throughput screen and discovered a small molecule hit that is highly selective for ERAP1. (4a,5,6,8,8a)-5-(2-(Furan-3-yl)ethyl)-8-hydroxy-5,6,8a-trimethyl-3,4,4a,5,6,7,8,8a-octahydronaphthalene-1-carboxylic acid is a natural product found in that constitutes a submicromolar, highly selective, and cell-active modulator of ERAP1. Although the compound activates hydrolysis of small model substrates, it is a competitive inhibitor for physiologically relevant longer peptides. Crystallographic analysis confirmed that the compound targets the regulatory site of the enzyme that normally binds the C-terminus of the peptide substrate. Our findings constitute a novel starting point for the development of selective ERAP1 modulators that have potential for further clinical development.
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http://dx.doi.org/10.1021/acs.jmedchem.9b02123DOI Listing
March 2020

The TAB1-p38α complex aggravates myocardial injury and can be targeted by small molecules.

JCI Insight 2018 08 23;3(16). Epub 2018 Aug 23.

British Heart Foundation Centre of Excellence, The Rayne Institute, St. Thomas' Hospital, and.

Inhibiting MAPK14 (p38α) diminishes cardiac damage in myocardial ischemia. During myocardial ischemia, p38α interacts with TAB1, a scaffold protein, which promotes p38α autoactivation; active p38α (pp38α) then transphosphorylates TAB1. Previously, we solved the X-ray structure of the p38α-TAB1 (residues 384-412) complex. Here, we further characterize the interaction by solving the structure of the pp38α-TAB1 (residues 1-438) complex in the active state. Based on this information, we created a global knock-in (KI) mouse with substitution of 4 residues on TAB1 that we show are required for docking onto p38α. Whereas ablating p38α or TAB1 resulted in early embryonal lethality, the TAB1-KI mice were viable and had no appreciable alteration in their lymphocyte repertoire or myocardial transcriptional profile; nonetheless, following in vivo regional myocardial ischemia, infarction volume was significantly reduced and the transphosphorylation of TAB1 was disabled. Unexpectedly, the activation of myocardial p38α during ischemia was only mildly attenuated in TAB1-KI hearts. We also identified a group of fragments able to disrupt the interaction between p38α and TAB1. We conclude that the interaction between the 2 proteins can be targeted with small molecules. The data reveal that it is possible to selectively inhibit signaling downstream of p38α to attenuate ischemic injury.
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http://dx.doi.org/10.1172/jci.insight.121144DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6141180PMC
August 2018

Structural and mechanistic basis of differentiated inhibitors of the acute pancreatitis target kynurenine-3-monooxygenase.

Nat Commun 2017 06 12;8:15827. Epub 2017 Jun 12.

Platform Technologies and Science, GlaxoSmithKline, Stevenage SG1 2NY, UK.

Kynurenine-3-monooxygenase (KMO) is a key FAD-dependent enzyme of tryptophan metabolism. In animal models, KMO inhibition has shown benefit in neurodegenerative diseases such as Huntington's and Alzheimer's. Most recently it has been identified as a target for acute pancreatitis multiple organ dysfunction syndrome (AP-MODS); a devastating inflammatory condition with a mortality rate in excess of 20%. Here we report and dissect the molecular mechanism of action of three classes of KMO inhibitors with differentiated binding modes and kinetics. Two novel inhibitor classes trap the catalytic flavin in a previously unobserved tilting conformation. This correlates with picomolar affinities, increased residence times and an absence of the peroxide production seen with previous substrate site inhibitors. These structural and mechanistic insights culminated in GSK065(C1) and GSK366(C2), molecules suitable for preclinical evaluation. Moreover, revising the repertoire of flavin dynamics in this enzyme class offers exciting new opportunities for inhibitor design.
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http://dx.doi.org/10.1038/ncomms15827DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5477544PMC
June 2017

Development of a Series of Kynurenine 3-Monooxygenase Inhibitors Leading to a Clinical Candidate for the Treatment of Acute Pancreatitis.

J Med Chem 2017 04 11;60(8):3383-3404. Epub 2017 Apr 11.

MRC Centre for Inflammation Research, University of Edinburgh , Edinburgh EH16 4TJ, UK.

Recently, we reported a novel role for KMO in the pathogenesis of acute pancreatitis (AP). A number of inhibitors of kynurenine 3-monooxygenase (KMO) have previously been described as potential treatments for neurodegenerative conditions and particularly for Huntington's disease. However, the inhibitors reported to date have insufficient aqueous solubility relative to their cellular potency to be compatible with the intravenous (iv) dosing route required in AP. We have identified and optimized a novel series of high affinity KMO inhibitors with favorable physicochemical properties. The leading example is exquisitely selective, has low clearance in two species, prevents lung and kidney damage in a rat model of acute pancreatitis, and is progressing into preclinical development.
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http://dx.doi.org/10.1021/acs.jmedchem.7b00055DOI Listing
April 2017

Whole Cell Target Engagement Identifies Novel Inhibitors of Mycobacterium tuberculosis Decaprenylphosphoryl-β-d-ribose Oxidase.

ACS Infect Dis 2015 Dec 25;1(12):615-26. Epub 2015 Aug 25.

School of Biosciences, University of Birmingham , Birmingham B15 2TT, United Kingdom.

We have targeted the Mycobacterium tuberculosis decaprenylphosphoryl-β-d-ribose oxidase (Mt-DprE1) for potential chemotherapeutic intervention of tuberculosis. A multicopy suppression strategy that overexpressed Mt-DprE1 in M. bovis BCG was used to profile the publically available GlaxoSmithKline antimycobacterial compound set, and one compound (GSK710) was identified that showed an 8-fold higher minimum inhibitory concentration relative to the control strain. Analogues of GSK710 show a clear relationship between whole cell potency and in vitro activity using an enzymatic assay employing recombinant Mt-DprE1, with binding affinity measured by fluorescence quenching of the flavin cofactor of the enzyme. M. bovis BCG spontaneous resistant mutants to GSK710 and a closely related analogue were isolated and sequencing of ten such mutants revealed a single point mutation at two sites, E221Q or G248S within DprE1, providing further evidence that DprE1 is the main target of these compounds. Finally, time-lapse microscopy experiments showed that exposure of M. tuberculosis to a compound of this series arrests bacterial growth rapidly followed by a slower cytolysis phase.
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http://dx.doi.org/10.1021/acsinfecdis.5b00065DOI Listing
December 2015

Kynurenine-3-monooxygenase inhibition prevents multiple organ failure in rodent models of acute pancreatitis.

Nat Med 2016 Feb 11;22(2):202-9. Epub 2016 Jan 11.

Medical Research Council Centre for Inflammation Research, University of Edinburgh, Edinburgh, UK.

Acute pancreatitis (AP) is a common and devastating inflammatory condition of the pancreas that is considered to be a paradigm of sterile inflammation leading to systemic multiple organ dysfunction syndrome (MODS) and death. Acute mortality from AP-MODS exceeds 20% (ref. 3), and the lifespans of those who survive the initial episode are typically shorter than those of the general population. There are no specific therapies available to protect individuals from AP-MODS. Here we show that kynurenine-3-monooxygenase (KMO), a key enzyme of tryptophan metabolism, is central to the pathogenesis of AP-MODS. We created a mouse strain that is deficient for Kmo (encoding KMO) and that has a robust biochemical phenotype that protects against extrapancreatic tissue injury to the lung, kidney and liver in experimental AP-MODS. A medicinal chemistry strategy based on modifications of the kynurenine substrate led to the discovery of the oxazolidinone GSK180 as a potent and specific inhibitor of KMO. The binding mode of the inhibitor in the active site was confirmed by X-ray co-crystallography at 3.2 Å resolution. Treatment with GSK180 resulted in rapid changes in the levels of kynurenine pathway metabolites in vivo, and it afforded therapeutic protection against MODS in a rat model of AP. Our findings establish KMO inhibition as a novel therapeutic strategy in the treatment of AP-MODS, and they open up a new area for drug discovery in critical illness.
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http://dx.doi.org/10.1038/nm.4020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4871268PMC
February 2016

Lead discovery for human kynurenine 3-monooxygenase by high-throughput RapidFire mass spectrometry.

J Biomol Screen 2014 Apr 31;19(4):508-15. Epub 2013 Dec 31.

1Department of Biological Sciences, GlaxoSmithKline, Stevenage, UK.

Kynurenine 3-monooxygenase (KMO) is a therapeutically important target on the eukaryotic tryptophan catabolic pathway, where it converts L-kynurenine (Kyn) to 3-hydroxykynurenine (3-HK). We have cloned and expressed the human form of this membrane protein as a full-length GST-fusion in a recombinant baculovirus expression system. An enriched membrane preparation was used for a directed screen of approximately 78,000 compounds using a RapidFire mass spectrometry (RF-MS) assay. The RapidFire platform provides an automated solid-phase extraction system that gives a throughput of approximately 7 s per well to the mass spectrometer, where direct measurement of both the substrate and product allowed substrate conversion to be determined. The RF-MS methodology is insensitive to assay interference, other than where compounds have the same nominal mass as Kyn or 3-HK and produce the same mass transition on fragmentation. These instances could be identified by comparison with the product-only data. The screen ran with excellent performance (average Z' value 0.8) and provided several tractable hit series for further investigation.
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http://dx.doi.org/10.1177/1087057113518069DOI Listing
April 2014

Development of an insect-cell-based assay for detection of kinase inhibition using NF-kappaB-inducing kinase as a paradigm.

Biochem J 2009 Apr;419(1):65-73

Biological Reagents & Assay Development, GlaxoSmithKline R&D, New Frontiers Science Park, Third Avenue, Harlow, Essex, CM19 5AW, UK.

Identification of small-molecule inhibitors by high-throughput screening necessitates the development of robust, reproducible and cost-effective assays. The assay approach adopted may utilize isolated proteins or whole cells containing the target of interest. To enable protein-based assays, the baculovirus expression system is commonly used for generation and isolation of recombinant proteins. We have applied the baculovirus system into a cell-based assay format using NIK [NF-kappaB (nuclear factor kappaB)-inducing kinase] as a paradigm. We illustrate the use of the insect-cell-based assay in monitoring the activity of NIK against its physiological downstream substrate IkappaB (inhibitor of NF-kappaB) kinase-1. The assay was robust, yielding a signal/background ratio of 2:1 and an average Z' value of >0.65 when used to screen a focused compound set. Using secondary assays to validate a selection of the hits, we identified a compound that (i) was non-cytotoxic, (ii) interacted directly with NIK, and (iii) inhibited lymphotoxin-induced NF-kappaB p52 translocation to the nucleus. The insect cell assay represents a novel approach to monitoring kinase inhibition, with major advantages over other cell-based systems including ease of use, amenability to scale-up, protein expression levels and the flexibility to express a number of proteins by infecting with numerous baculoviruses.
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http://dx.doi.org/10.1042/BJ20081646DOI Listing
April 2009

Fluorescence-based assays.

Prog Med Chem 2005 ;43:19-48

National Institute for Medical Research, The Ridgeway, Mill Hill, London, UK.

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http://dx.doi.org/10.1016/S0079-6468(05)43002-7DOI Listing
November 2005

A modular, fully integrated ultra-high-throughput screening system based on confocal fluorescence analysis techniques.

J Biomol Screen 2003 Dec;8(6):648-59

Evotec OAI/Evotec Technologies, Hamburg, Germany.

The rapid increase in size of compound libraries, as well as new targets emerging from the Human Genome Project, require progress in ultra-high-throughput screening (uHTS) systems. In a joint effort with scientists and engineers from the biotech and the pharmaceutical industry, a modular, fully integrated system for miniaturized uHTS was developed. The goal was to achieve high data quality in small assay volumes (1-4 microL) combined with reliable and unattended operation. Two new confocal fluorescence readers have been designed. One of the instruments is a 4-channel confocal fluorescence reader, measuring with 4 objectives in parallel. The fluorescence readout is based on single-molecule detection methods, allowing high sensitivity at low tracer concentrations and delivering an information-rich output. The other instrument is a confocal fluorescence imaging reader, where the images are analyzed in terms of generic patterns and quantified in units of intensity per pixel. Both readers are spanning the application range from assays with isolated targets in homogenous solution or membrane vesicle-based assays (4-channel reader) to cell-based assays (imaging reader). Results from a comprehensive test on these assay types demonstrate the high quality and robustness of this screening system.
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http://dx.doi.org/10.1177/1087057103258475DOI Listing
December 2003