1
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Picco G, Rao Y, Al Saedi A, Lee Y, Vieira SF, Bhosle S, May K, Herranz-Ors C, Walker SJ, Shenje R, Dincer C, Gibson F, Banerjee R, Hewitson Z, Werner T, Cottom JE, Peng Y, Deng N, Landis P, Conticelli D, McCarten K, Bush J, Sharma M, Lightfoot H, House D, Milford E, Grant EK, Glogowski MP, Wagner CD, Bantscheff M, Rutkowska-Klute A, Network Uk Group CM, Zappacosta F, Pettinger J, Barthorpe S, Eberl HC, Jones BT, Schneck JL, Murphy DJ, Voest EE, Taygerly JP, DeMartino MP, Coelho MA, Houseley J, Sharma G, Schwartz BJ, Garnett MJ. Novel WRN Helicase Inhibitors Selectively Target Microsatellite Unstable Cancer Cells. Cancer Discov 2024:742950. [PMID: 38587317 DOI: 10.1158/2159-8290.cd-24-0052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Revised: 03/26/2024] [Accepted: 04/05/2024] [Indexed: 04/09/2024]
Abstract
Microsatellite-unstable (MSI) cancers require WRN helicase to resolve replication stress due to expanded DNA (TA)n-dinucleotide repeats. WRN is a promising synthetic lethal target for MSI tumours, and WRN inhibitors are in development. Here, we used CRISPR-Cas9 base editing to map WRN residues critical for MSI cells, validating the helicase domain as the primary drug target. Fragment-based screening led to the development of potent and highly selective WRN helicase covalent inhibitors. These compounds selectively suppressed MSI model growth In vitro and In vivo by mimicking WRN loss, inducing DNA double-strand breaks at expanded TA-repeats and DNA damage. Assessment of biomarkers in preclinical models linked TA-repeat expansions and mismatch repair (MMR) alterations to compound activity. Efficacy was confirmed in immunotherapy-resistant organoids and patient-derived xenograft (PDX) models. The discovery of potent, selective covalent WRN inhibitors provides proof of concept for synthetic-lethal targeting of WRN in MSI cancer and tools to dissect WRN biology.
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Affiliation(s)
| | - Yanhua Rao
- GSK, Upper Providence, PA, US 19426, United States
| | | | - Yang Lee
- GSK, Upper Providence, PA, US 19426, United States
| | | | | | - Kieron May
- Babraham Institute, Cambridge, United Kingdom
| | | | | | | | - Cansu Dincer
- Wellcome Sanger Institute, Cambridge, United Kingdom
| | - Freddy Gibson
- Wellcome Sanger Institute, Cambridge, United Kingdom
| | | | - Zoe Hewitson
- Wellcome Sanger Institute, Cambridge, United Kingdom
| | | | - Joshua E Cottom
- GlaxoSmithKline (United States), Upper Providence, PA, United States
| | - Yang Peng
- The University of Texas MD Anderson Cancer Center, Houston, TEXAS, United States
| | | | | | - Daniela Conticelli
- University of Torino, Candiolo Cancer Institute - FPO,IRCCS, Candiolo, TO, Italy
| | | | | | - Mamta Sharma
- Wellcome Sanger Institute, Cambridge, United Kingdom
| | | | | | | | | | | | | | | | | | | | | | | | - Syd Barthorpe
- Wellcome Trust Sanger Institute, Hinxton, United Kingdom
| | | | | | | | | | - Emile E Voest
- Netherlands Cancer Institute, Amsterdam, Netherlands
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2
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Barton LS, Callahan JF, Cantizani J, Concha NO, Cotillo Torrejon I, Goodwin NC, Joshi-Pangu A, Kiesow TJ, McAtee JJ, Mellinger M, Nixon CJ, Padrón-Barthe L, Patterson JR, Pearson ND, Pouliot JJ, Rendina AR, Buitrago Santanilla A, Schneck JL, Sanz O, Thalji RK, Ward P, Williams SP, King BW. Exploration of the P1 residue in 3CL protease inhibitors leading to the discovery of a 2-tetrahydrofuran P1 replacement. Bioorg Med Chem 2024; 100:117618. [PMID: 38309201 DOI: 10.1016/j.bmc.2024.117618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 01/19/2024] [Accepted: 01/26/2024] [Indexed: 02/05/2024]
Abstract
The virally encoded 3C-like protease (3CLpro) is a well-validated drug target for the inhibition of coronaviruses including Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). Most inhibitors of 3CLpro are peptidomimetic, with a γ-lactam in place of Gln at the P1 position of the pseudopeptide chain. An effort was pursued to identify a viable alternative to the γ-lactam P1 mimetic which would improve physicochemical properties while retaining affinity for the target. Discovery of a 2-tetrahydrofuran as a suitable P1 replacement that is a potent enzymatic inhibitor of 3CLpro in SARS-CoV-2 virus is described herein.
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Affiliation(s)
- Linda S Barton
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States.
| | - James F Callahan
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | - Juan Cantizani
- GlaxoSmithKline, Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | - Nestor O Concha
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | | | - Nicole C Goodwin
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | - Amruta Joshi-Pangu
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | - Terry J Kiesow
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | - Jeff J McAtee
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | - Mark Mellinger
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | - Christopher J Nixon
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | | | - Jaclyn R Patterson
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | - Neil D Pearson
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | - Jeffrey J Pouliot
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | - Alan R Rendina
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | | | - Jessica L Schneck
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | - Olalla Sanz
- GlaxoSmithKline, Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | - Reema K Thalji
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | - Paris Ward
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | - Shawn P Williams
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
| | - Bryan W King
- GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, United States
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3
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Douglas LEJ, Reihill JA, Ho MWY, Axten JM, Campobasso N, Schneck JL, Rendina AR, Wilcoxen KM, Martin SL. A highly selective, cell-permeable furin inhibitor BOS-318 rescues key features of cystic fibrosis airway disease. Cell Chem Biol 2022; 29:947-957.e8. [PMID: 35202587 DOI: 10.1016/j.chembiol.2022.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 12/14/2021] [Accepted: 02/01/2022] [Indexed: 12/15/2022]
Abstract
In cystic fibrosis (CF), excessive furin activity plays a critical role in the activation of the epithelial sodium channel (ENaC), dysregulation of which contributes to airway dehydration, ineffective mucociliary clearance (MCC), and mucus obstruction. Here, we report a highly selective, cell-permeable furin inhibitor, BOS-318, that derives selectivity by eliciting the formation of a new, unexpected binding pocket independent of the active site catalytic triad. Using human ex vivo models, BOS-318 showed significant suppression of ENaC, which led to enhanced airway hydration and an ∼30-fold increase in MCC rate. Furin inhibition also protected ENaC from subsequent activation by neutrophil elastase, a soluble protease dominant in CF airways. Additional therapeutic benefits include protection against epithelial cell death induced by Pseudomonas aeruginosa exotoxin A. Our findings demonstrate the utility of selective furin inhibition as a mutation-agnostic approach that can correct features of CF airway pathophysiology in a manner expected to deliver therapeutic value.
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Affiliation(s)
- Lisa E J Douglas
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, Northern Ireland, UK
| | - James A Reihill
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, Northern Ireland, UK
| | - Melisa W Y Ho
- GlaxoSmithKline Research and Development, Collegeville, PA 19426, USA
| | - Jeffrey M Axten
- GlaxoSmithKline Research and Development, Collegeville, PA 19426, USA
| | - Nino Campobasso
- GlaxoSmithKline Research and Development, Collegeville, PA 19426, USA
| | - Jessica L Schneck
- GlaxoSmithKline Research and Development, Collegeville, PA 19426, USA
| | - Alan R Rendina
- GlaxoSmithKline Research and Development, Collegeville, PA 19426, USA
| | | | - S Lorraine Martin
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, Northern Ireland, UK.
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4
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Liddle J, Hutchinson JP, Kitchen S, Rowland P, Neu M, Cecconie T, Holmes DS, Jones E, Korczynska J, Koumantou D, Lea JD, Nickels L, Pemberton M, Phillipou A, Schneck JL, Sheehan H, Tinworth CP, Uings I, Wojno-Picon J, Young RJ, Stratikos E. Targeting the Regulatory Site of ER Aminopeptidase 1 Leads to the Discovery of a Natural Product Modulator of Antigen Presentation. J Med Chem 2020; 63:3348-3358. [PMID: 32109056 DOI: 10.1021/acs.jmedchem.9b02123] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
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. (4aR,5S,6R,8S,8aR)-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 Dodonaea viscosa 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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Affiliation(s)
- John Liddle
- Discovery Partnerships with Academia, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Jonathan P Hutchinson
- Medicinal Science and Technology, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Semra Kitchen
- Discovery Partnerships with Academia, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Paul Rowland
- Medicinal Science and Technology, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Margarete Neu
- Medicinal Science and Technology, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Ted Cecconie
- Medicinal Science and Technology, GlaxoSmithKline, Collegeville, Pennsylvania 19426, United States
| | - Duncan S Holmes
- Discovery Partnerships with Academia, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Emma Jones
- Medicinal Science and Technology, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Justyna Korczynska
- Medicinal Science and Technology, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Despoina Koumantou
- National Centre for Scientific Research "Demokritos", Patriarchou Gregoriou and Neapoleos 27, Agia Paraskevi, Athens 15341, Greece
| | - Jonathan D Lea
- Medicinal Science and Technology, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Leng Nickels
- Medicinal Science and Technology, GlaxoSmithKline, Collegeville, Pennsylvania 19426, United States
| | - Michelle Pemberton
- Medicinal Science and Technology, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Alex Phillipou
- Medicinal Science and Technology, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Jessica L Schneck
- Medicinal Science and Technology, GlaxoSmithKline, Collegeville, Pennsylvania 19426, United States
| | - Hester Sheehan
- Medicinal Science and Technology, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Christopher P Tinworth
- Medicinal Science and Technology, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Iain Uings
- Discovery Partnerships with Academia, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Justyna Wojno-Picon
- Medicinal Science and Technology, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Robert J Young
- Medicinal Science and Technology, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, U.K
| | - Efstratios Stratikos
- National Centre for Scientific Research "Demokritos", Patriarchou Gregoriou and Neapoleos 27, Agia Paraskevi, Athens 15341, Greece
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5
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McDevitt PJ, Schneck JL, Diaz E, Hou W, Huddleston MJ, Matico RE, McCormick PM, Kirkpatrick RB. A Scalable Platform for Producing Recombinant Nucleosomes with Codified Histone Methyltransferase Substrate Preferences. Protein Expr Purif 2019; 164:105455. [PMID: 31306746 DOI: 10.1016/j.pep.2019.105455] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 07/09/2019] [Accepted: 07/11/2019] [Indexed: 11/15/2022]
Abstract
Wolf-Hirschhorn Syndrome Candidate 1 (WHSC1; also known as NSD2) is a SET domain-containing histone lysine methyltransferase. A chromosomal translocation occurs in 15-20% of multiple myeloma patients and is associated with increased production of WHSC1 and poor clinical prognosis. To define the substrate requirements of NSD2, we established a platform for the large-scale production of recombinant polynucleosomes, based on authentic human histone proteins, expressed in E. coli, and complexed with linearized DNA. A brief survey of methyltransferases whose substrate requirements are recorded in the literature yielded expected results, lending credence to the fitness of our approach. This platform was readily 'codified' with respect to both position and extent of methylation at histone 3 lysines 18 and 36 and led to the conclusion that the most readily discernible activity of NSD2 in contact with a nucleosome substrate is dimethylation of histone 3 lysine 36. We further explored reaction mechanism, and conclude a processive, rather than distributive mechanism best describes the interaction of NSD2 with intact nucleosome substrates. The methods developed feature scale and flexibility and are suited to thorough pharmaceutical-scale drug discovery campaigns.
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Affiliation(s)
- Patrick J McDevitt
- GlaxoSmithKline Pharmaceutical Company, 1250 South Collegeville Road, Collegeville, PA, 19426-0989, USA.
| | - Jessica L Schneck
- GlaxoSmithKline Pharmaceutical Company, 1250 South Collegeville Road, Collegeville, PA, 19426-0989, USA
| | - Elsie Diaz
- Janssen Pharmaceutical Companies of Johnson and Johnson, Philadelphia, PA, USA
| | - Wangfang Hou
- GlaxoSmithKline Pharmaceutical Company, 1250 South Collegeville Road, Collegeville, PA, 19426-0989, USA
| | - Michael J Huddleston
- GlaxoSmithKline Pharmaceutical Company, 1250 South Collegeville Road, Collegeville, PA, 19426-0989, USA
| | - Rosalie E Matico
- Janssen Pharmaceutical Companies of Johnson and Johnson, Philadelphia, PA, USA
| | - Patricia M McCormick
- GlaxoSmithKline Pharmaceutical Company, 1250 South Collegeville Road, Collegeville, PA, 19426-0989, USA
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6
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Ramanjulu JM, Pesiridis GS, Yang J, Concha N, Singhaus R, Zhang SY, Tran JL, Moore P, Lehmann S, Eberl HC, Muelbaier M, Schneck JL, Clemens J, Adam M, Mehlmann J, Romano J, Morales A, Kang J, Leister L, Graybill TL, Charnley AK, Ye G, Nevins N, Behnia K, Wolf AI, Kasparcova V, Nurse K, Wang L, Puhl AC, Li Y, Klein M, Hopson CB, Guss J, Bantscheff M, Bergamini G, Reilly MA, Lian Y, Duffy KJ, Adams J, Foley KP, Gough PJ, Marquis RW, Smothers J, Hoos A, Bertin J. Author Correction: Design of amidobenzimidazole STING receptor agonists with systemic activity. Nature 2019; 570:E53. [PMID: 31142845 DOI: 10.1038/s41586-019-1265-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Change history: In this Letter, author Ana Puhl was inadvertently omitted; this error has been corrected online.An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Affiliation(s)
- Joshi M Ramanjulu
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA.
| | - G Scott Pesiridis
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Jingsong Yang
- Immuno-Oncology & Combinations DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Nestor Concha
- Platform Technology & Science, GlaxoSmithKline, Collegeville, PA, USA
| | - Robert Singhaus
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Shu-Yun Zhang
- Immuno-Oncology & Combinations DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Jean-Luc Tran
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Patrick Moore
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | | | | | | | - Jessica L Schneck
- Platform Technology & Science, GlaxoSmithKline, Collegeville, PA, USA
| | - Jim Clemens
- Platform Technology & Science, GlaxoSmithKline, Collegeville, PA, USA
| | - Michael Adam
- Immuno-Oncology & Combinations DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - John Mehlmann
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Joseph Romano
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Angel Morales
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - James Kang
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Lara Leister
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Todd L Graybill
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Adam K Charnley
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Guosen Ye
- Platform Technology & Science, GlaxoSmithKline, Collegeville, PA, USA
| | - Neysa Nevins
- Platform Technology & Science, GlaxoSmithKline, Collegeville, PA, USA
| | - Kamelia Behnia
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Amaya I Wolf
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Viera Kasparcova
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Kelvin Nurse
- Platform Technology & Science, GlaxoSmithKline, Collegeville, PA, USA
| | - Liping Wang
- Platform Technology & Science, GlaxoSmithKline, Collegeville, PA, USA
| | - Ana C Puhl
- Platform Technology & Science, GlaxoSmithKline, Collegeville, PA, USA
| | - Yue Li
- Platform Technology & Science, GlaxoSmithKline, Collegeville, PA, USA
| | - Michael Klein
- Platform Technology & Science, GlaxoSmithKline, Collegeville, PA, USA
| | | | - Jeffrey Guss
- Platform Technology & Science, GlaxoSmithKline, Collegeville, PA, USA
| | | | | | - Michael A Reilly
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Yiqian Lian
- Immuno-Oncology & Combinations DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Kevin J Duffy
- Immuno-Oncology & Combinations DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Jerry Adams
- Immuno-Oncology & Combinations DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Kevin P Foley
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Peter J Gough
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Robert W Marquis
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - James Smothers
- Immuno-Oncology & Combinations DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - Axel Hoos
- Immuno-Oncology & Combinations DPU, GlaxoSmithKline, Collegeville, PA, USA
| | - John Bertin
- Pattern Recognition Receptor DPU, GlaxoSmithKline, Collegeville, PA, USA
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7
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Poulin MB, Schneck JL, Matico RE, Hou W, McDevitt PJ, Holbert M, Schramm VL. Nucleosome Binding Alters the Substrate Bonding Environment of Histone H3 Lysine 36 Methyltransferase NSD2. J Am Chem Soc 2016; 138:6699-702. [PMID: 27183271 PMCID: PMC6702673 DOI: 10.1021/jacs.6b01612] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Nuclear receptor-binding SET domain protein 2 (NSD2) is a histone H3 lysine 36 (H3K36)-specific methyltransferase enzyme that is overexpressed in a number of cancers, including multiple myeloma. NSD2 binds to S-adenosyl-l-methionine (SAM) and nucleosome substrates to catalyze the transfer of a methyl group from SAM to the ε-amino group of histone H3K36. Equilibrium binding isotope effects and density functional theory calculations indicate that the SAM methyl group is sterically constrained in complex with NSD2, and that this steric constraint is released upon nucleosome binding. Together, these results show that nucleosome binding to NSD2 induces a significant change in the chemical environment of enzyme-bound SAM.
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Affiliation(s)
- Myles B. Poulin
- Department of Biochemistry, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, United States
| | - Jessica L. Schneck
- Biological Sciences, Platform Technology and Science, GlaxoSmithKline, Collegeville, Pennsylvania 19426, United States
| | - Rosalie E. Matico
- Biological Sciences, Platform Technology and Science, GlaxoSmithKline, Collegeville, Pennsylvania 19426, United States
| | - Wangfang Hou
- Biological Sciences, Platform Technology and Science, GlaxoSmithKline, Collegeville, Pennsylvania 19426, United States
| | - Patrick J. McDevitt
- Biological Sciences, Platform Technology and Science, GlaxoSmithKline, Collegeville, Pennsylvania 19426, United States
| | - Marc Holbert
- Biological Sciences, Platform Technology and Science, GlaxoSmithKline, Collegeville, Pennsylvania 19426, United States
| | - Vern L. Schramm
- Department of Biochemistry, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, United States
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8
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Poulin MB, Schneck JL, Matico RE, McDevitt PJ, Huddleston MJ, Hou W, Johnson NW, Thrall SH, Meek TD, Schramm VL. Transition state for the NSD2-catalyzed methylation of histone H3 lysine 36. Proc Natl Acad Sci U S A 2016; 113:1197-201. [PMID: 26787850 PMCID: PMC4747696 DOI: 10.1073/pnas.1521036113] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Nuclear receptor SET domain containing protein 2 (NSD2) catalyzes the methylation of histone H3 lysine 36 (H3K36). It is a determinant in Wolf-Hirschhorn syndrome and is overexpressed in human multiple myeloma. Despite the relevance of NSD2 to cancer, there are no potent, selective inhibitors of this enzyme reported. Here, a combination of kinetic isotope effect measurements and quantum chemical modeling was used to provide subangstrom details of the transition state structure for NSD2 enzymatic activity. Kinetic isotope effects were measured for the methylation of isolated HeLa cell nucleosomes by NSD2. NSD2 preferentially catalyzes the dimethylation of H3K36 along with a reduced preference for H3K36 monomethylation. Primary Me-(14)C and (36)S and secondary Me-(3)H3, Me-(2)H3, 5'-(14)C, and 5'-(3)H2 kinetic isotope effects were measured for the methylation of H3K36 using specifically labeled S-adenosyl-l-methionine. The intrinsic kinetic isotope effects were used as boundary constraints for quantum mechanical calculations for the NSD2 transition state. The experimental and calculated kinetic isotope effects are consistent with an SN2 chemical mechanism with methyl transfer as the first irreversible chemical step in the reaction mechanism. The transition state is a late, asymmetric nucleophilic displacement with bond separation from the leaving group at (2.53 Å) and bond making to the attacking nucleophile (2.10 Å) advanced at the transition state. The transition state structure can be represented in a molecular electrostatic potential map to guide the design of inhibitors that mimic the transition state geometry and charge.
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Affiliation(s)
- Myles B Poulin
- Department of Biochemistry, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY 10461
| | - Jessica L Schneck
- Biological Sciences, Platform Technology and Science, GlaxoSmithKline, Collegeville, PA 19426
| | - Rosalie E Matico
- Biological Sciences, Platform Technology and Science, GlaxoSmithKline, Collegeville, PA 19426
| | - Patrick J McDevitt
- Biological Sciences, Platform Technology and Science, GlaxoSmithKline, Collegeville, PA 19426
| | - Michael J Huddleston
- Biological Sciences, Platform Technology and Science, GlaxoSmithKline, Collegeville, PA 19426
| | - Wangfang Hou
- Biological Sciences, Platform Technology and Science, GlaxoSmithKline, Collegeville, PA 19426
| | - Neil W Johnson
- Cancer Epigenetics Discovery Performance Unit, GlaxoSmithKline, Collegeville, PA 19426
| | - Sara H Thrall
- Biological Sciences, Platform Technology and Science, GlaxoSmithKline, Collegeville, PA 19426
| | - Thomas D Meek
- Biological Sciences, Platform Technology and Science, GlaxoSmithKline, Collegeville, PA 19426
| | - Vern L Schramm
- Department of Biochemistry, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY 10461;
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Pappalardi MB, Schneck JL, Matico R, Huddleston M, Hou W, McDevitt P, Annan R, Kirkpatrick R, Kruger R. Abstract 4357: Key differences revealed in NSD2 kinetics using truncated versus full-length protein. Cancer Res 2015. [DOI: 10.1158/1538-7445.am2015-4357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Histone lysine methyltransferases (HKMTs) are a class of enzymes that transfer a methyl group from S-adenosyl-L-methionine (SAM) to lysine residues on histone tails. The nuclear receptor SET domain-containing (NSD) family of proteins is known to methylate lysine 36 of histone H3 (H3K36). Abnormal methylation at H3K36 has been widely implicated in a variety of cancers and diseases, therefore, the enzymes responsible for this posttranslational modification are of interest from a drug-discovery standpoint. NSD2 (MMSET/WHSC1), a representative of this family, was found to be highly expressed in a multitude of human tumors and has been directly linked to multiple myeloma and Wolf-Hirschhorn syndrome. The chromosomal translocation t(4:14)(p16;q32) that occurs in 15% of myeloma patients is associated with both increased production of NSD2 and poor prognosis while loss of the NSD2 gene at the 4p16.3 region results in Wolf-Hirschhorn syndrome. In order to better understand the multi-dimensional nature of NSD2, full-length and truncated versions of the protein were generated to evaluate NSD2 kinetics. The biochemical activity of each NSD2 construct was assessed using (1) a radioactive assay measuring 3H transfer from SAM to the histone substrate or (2) LC-MS/MS analysis of the NSD2-dependent product. Full-length NSD2 prefers a nucleosomal substrate; whereas, C-terminal truncation of a highly charged region (AA 12-14-1240) resulted in a loss of nucleosomal activity and a gain of activity using a peptide derived from Histone H3. Additionally, LC-MS/MS mapping revealed a shift in the methylation site from H3K36 to H3K18 when using the truncated system. More detailed kinetic analysis revealed that the FL/nucleosome reaction catalyzes processive methylation while truncated NSD2 methylates the peptide distributively. Lastly, key changes in inhibitor specificity were observed. An alternative C terminal region, residues 1341-1365, was required to maintain potency of the product inhibitor SAH but not the close analog sinefungin. This may be indicative of the ping-pong kinetics proposed for FL NSD2 implying that SAH targets the NSD2-nucleosome bound form of the enzyme (UC vs. nucleosome) while sinefungin does not (NC vs. nucleosome). While a truncated NSD2/peptide system would be much easier to screen, profile and characterize in the search for inhibitors, the results found herein indicate that screening a full-length NSD2/nucleosome system may be more physiologically relevant.
Citation Format: Melissa B. Pappalardi, Jessica L. Schneck, Rosalie Matico, Michael Huddleston, Wangfang Hou, Patrick McDevitt, Roland Annan, Robert Kirkpatrick, Ryan Kruger. Key differences revealed in NSD2 kinetics using truncated versus full-length protein. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4357. doi:10.1158/1538-7445.AM2015-4357
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Billiard J, Dennison JB, Briand J, Annan RS, Chai D, Colón M, Dodson CS, Gilbert SA, Greshock J, Jing J, Lu H, McSurdy-Freed JE, Orband-Miller LA, Mills GB, Quinn CJ, Schneck JL, Scott GF, Shaw AN, Waitt GM, Wooster RF, Duffy KJ. Quinoline 3-sulfonamides inhibit lactate dehydrogenase A and reverse aerobic glycolysis in cancer cells. Cancer Metab 2013; 1:19. [PMID: 24280423 PMCID: PMC4178217 DOI: 10.1186/2049-3002-1-19] [Citation(s) in RCA: 144] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 08/27/2013] [Indexed: 12/13/2022] Open
Abstract
Background Most normal cells in the presence of oxygen utilize glucose for mitochondrial oxidative phosphorylation. In contrast, many cancer cells rapidly convert glucose to lactate in the cytosol, a process termed aerobic glycolysis. This glycolytic phenotype is enabled by lactate dehydrogenase (LDH), which catalyzes the inter-conversion of pyruvate and lactate. The purpose of this study was to identify and characterize potent and selective inhibitors of LDHA. Methods High throughput screening and lead optimization were used to generate inhibitors of LDHA enzymatic activity. Effects of these inhibitors on metabolism were evaluated using cell-based lactate production, oxygen consumption, and 13C NMR spectroscopy assays. Changes in comprehensive metabolic profile, cell proliferation, and apoptosis were assessed upon compound treatment. Results 3-((3-carbamoyl-7-(3,5-dimethylisoxazol-4-yl)-6-methoxyquinolin-4-yl) amino) benzoic acid was identified as an NADH-competitive LDHA inhibitor. Lead optimization yielded molecules with LDHA inhibitory potencies as low as 2 nM and 10 to 80-fold selectivity over LDHB. Molecules in this family rapidly and profoundly inhibited lactate production rates in multiple cancer cell lines including hepatocellular and breast carcinomas. Consistent with selective inhibition of LDHA, the most sensitive breast cancer cell lines to lactate inhibition in hypoxic conditions were cells with low expression of LDHB. Our inhibitors increased rates of oxygen consumption in hepatocellular carcinoma cells at doses up to 3 microM, while higher concentrations directly inhibited mitochondrial function. Analysis of more than 500 metabolites upon LDHA inhibition in Snu398 cells revealed that intracellular concentrations of glycolysis and citric acid cycle intermediates were increased, consistent with enhanced Krebs cycle activity and blockage of cytosolic glycolysis. Treatment with these compounds also potentiated PKM2 activity and promoted apoptosis in Snu398 cells. Conclusions Rapid chemical inhibition of LDHA by these quinoline 3-sulfonamids led to profound metabolic alterations and impaired cell survival in carcinoma cells making it a compelling strategy for treating solid tumors that rely on aerobic glycolysis for survival.
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Affiliation(s)
- Julia Billiard
- Cancer Metabolism DPU, GlaxoSmithKline, Collegeville PA, USA.
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11
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Rubach JK, Cui G, Schneck JL, Taylor AN, Zhao B, Smallwood A, Nevins N, Wisnoski D, Thrall SH, Meek TD. The Amino-Acid Substituents of Dipeptide Substrates of Cathepsin C Can Determine the Rate-Limiting Steps of Catalysis. Biochemistry 2012; 51:7551-68. [DOI: 10.1021/bi300719b] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jon K. Rubach
- Department
of Biological Reagents and Assay Development, §Department of Computational and Structural
Chemistry, and ∥Department of Screening and Compound Profiling, GlaxoSmithKline Pharmaceuticals, 1250 South Collegeville
Road, Collegeville, Pennsylvania 19426, United States
| | - Guanglei Cui
- Department
of Biological Reagents and Assay Development, §Department of Computational and Structural
Chemistry, and ∥Department of Screening and Compound Profiling, GlaxoSmithKline Pharmaceuticals, 1250 South Collegeville
Road, Collegeville, Pennsylvania 19426, United States
| | - Jessica L. Schneck
- Department
of Biological Reagents and Assay Development, §Department of Computational and Structural
Chemistry, and ∥Department of Screening and Compound Profiling, GlaxoSmithKline Pharmaceuticals, 1250 South Collegeville
Road, Collegeville, Pennsylvania 19426, United States
| | - Amy N. Taylor
- Department
of Biological Reagents and Assay Development, §Department of Computational and Structural
Chemistry, and ∥Department of Screening and Compound Profiling, GlaxoSmithKline Pharmaceuticals, 1250 South Collegeville
Road, Collegeville, Pennsylvania 19426, United States
| | - Baoguang Zhao
- Department
of Biological Reagents and Assay Development, §Department of Computational and Structural
Chemistry, and ∥Department of Screening and Compound Profiling, GlaxoSmithKline Pharmaceuticals, 1250 South Collegeville
Road, Collegeville, Pennsylvania 19426, United States
| | - Angela Smallwood
- Department
of Biological Reagents and Assay Development, §Department of Computational and Structural
Chemistry, and ∥Department of Screening and Compound Profiling, GlaxoSmithKline Pharmaceuticals, 1250 South Collegeville
Road, Collegeville, Pennsylvania 19426, United States
| | - Neysa Nevins
- Department
of Biological Reagents and Assay Development, §Department of Computational and Structural
Chemistry, and ∥Department of Screening and Compound Profiling, GlaxoSmithKline Pharmaceuticals, 1250 South Collegeville
Road, Collegeville, Pennsylvania 19426, United States
| | - David Wisnoski
- Department
of Biological Reagents and Assay Development, §Department of Computational and Structural
Chemistry, and ∥Department of Screening and Compound Profiling, GlaxoSmithKline Pharmaceuticals, 1250 South Collegeville
Road, Collegeville, Pennsylvania 19426, United States
| | - Sara H. Thrall
- Department
of Biological Reagents and Assay Development, §Department of Computational and Structural
Chemistry, and ∥Department of Screening and Compound Profiling, GlaxoSmithKline Pharmaceuticals, 1250 South Collegeville
Road, Collegeville, Pennsylvania 19426, United States
| | - Thomas D. Meek
- Department
of Biological Reagents and Assay Development, §Department of Computational and Structural
Chemistry, and ∥Department of Screening and Compound Profiling, GlaxoSmithKline Pharmaceuticals, 1250 South Collegeville
Road, Collegeville, Pennsylvania 19426, United States
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Jiang Y, Schneck JL, Grimes M, Taylor AN, Hou W, Thrall SH, Sweitzer SM. Methyltransferases prefer monomer over core-trimmed nucleosomes as in vitro substrates. Anal Biochem 2011; 415:84-6. [PMID: 21459076 DOI: 10.1016/j.ab.2011.03.037] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Revised: 03/28/2011] [Accepted: 03/29/2011] [Indexed: 11/23/2022]
Abstract
Epigenetics is an area of increasing interest for drug discovery, driving the need for assays that use nucleosome substrates. Our studies showed that SUV39H1, a histone lysine methyltransferase, and Dnmt3b/Dnmt3L, a DNA methyltransferase, both exhibited approximately five times more activity on monomer nucleosomes than on DNA-core-trimmed nucleosomes in a scintillation proximity assay (SPA). The methyltransferases recognize and have a preference for nucleosomes with longer DNA strands. Our findings suggest that the use of monomer nucleosomes as substrates using SPA technology could lead to more robust screening assays and potentially more specific small molecule inhibitors of epigenetic enzymes.
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Affiliation(s)
- Yong Jiang
- Department of Biological Reagents and Assay Development, GlaxoSmithKline, Collegeville, PA 19426, USA
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Schneck JL, Briand J, Chen S, Lehr R, McDevitt P, Zhao B, Smallwood A, Concha N, Oza K, Kirkpatrick R, Yan K, Villa JP, Meek TD, Thrall SH. Kinetic mechanism and rate-limiting steps of focal adhesion kinase-1. Biochemistry 2010; 49:7151-63. [PMID: 20597513 DOI: 10.1021/bi100824v] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Steady-state kinetic analysis of focal adhesion kinase-1 (FAK1) was performed using radiometric measurement of phosphorylation of a synthetic peptide substrate (Ac-RRRRRRSETDDYAEIID-NH(2), FAK-tide) which corresponds to the sequence of an autophosphorylation site in FAK1. Initial velocity studies were consistent with a sequential kinetic mechanism, for which apparent kinetic values k(cat) (0.052 +/- 0.001 s(-1)), K(MgATP) (1.2 +/- 0.1 microM), K(iMgATP) (1.3 +/- 0.2 microM), K(FAK-tide) (5.6 +/- 0.4 microM), and K(iFAK-tide) (6.1 +/- 1.1 microM) were obtained. Product and dead-end inhibition data indicated that enzymatic phosphorylation of FAK-tide by FAK1 was best described by a random bi bi kinetic mechanism, for which both E-MgADP-FAK-tide and E-MgATP-P-FAK-tide dead-end complexes form. FAK1 catalyzed the betagamma-bridge:beta-nonbridge positional oxygen exchange of [gamma-(18)O(4)]ATP in the presence of 1 mM [gamma-(18)O(4)]ATP and 1.5 mM FAK-tide with a progressive time course which was commensurate with catalysis, resulting in a rate of exchange to catalysis of k(x)/k(cat) = 0.14 +/- 0.01. These results indicate that phosphoryl transfer is reversible and that a slow kinetic step follows formation of the E-MgADP-P-FAK-tide complex. Further kinetic studies performed in the presence of the microscopic viscosogen sucrose revealed that solvent viscosity had no effect on k(cat)/K(FAK-tide), while k(cat) and k(cat)/K(MgATP) were both decreased linearly at increasing solvent viscosity. Crystallographic characterization of inactive versus AMP-PNP-liganded structures of FAK1 showed that a large conformational motion of the activation loop upon ATP binding may be an essential step during catalysis and would explain the viscosity effect observed on k(cat)/K(m) for MgATP but not on k(cat)/K(m) for FAK-tide. From the positional isotope exchange, viscosity, and structural data it may be concluded that enzyme turnover (k(cat)) is rate-limited by both reversible phosphoryl group transfer (k(forward) approximately 0.2 s(-1) and k(reverse) approximately 0.04 s(-1)) and a slow step (k(conf) approximately 0.1 s(-1)) which is probably the opening of the activation loop after phosphoryl group transfer but preceding product release.
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Affiliation(s)
- Jessica L Schneck
- Department of Biological Reagents, GlaxoSmithKline Pharmaceuticals, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426-0989, USA
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Schneck JL, Bandstra SR, Fried B, Sherma J. Thin Layer Chromatographic Analysis of Neutral Lipids in Snail Conditioned Water and Feces of Biomphalaria glabrata Infected with Echinostoma caproni. J LIQ CHROMATOGR R T 2009. [DOI: 10.1081/jlc-120039416] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Jessica L. Schneck
- a Department of Chemistry , Lafayette College , Easton , Pennsylvania , USA
| | - Sharon R. Bandstra
- a Department of Chemistry , Lafayette College , Easton , Pennsylvania , USA
| | - Bernard Fried
- b Department of Biology , Lafayette College , Easton , Pennsylvania , 18042 , USA
| | - Joseph Sherma
- a Department of Chemistry , Lafayette College , Easton , Pennsylvania , USA
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Schneck JL, Villa JP, McDevitt P, McQueney MS, Thrall SH, Meek TD. Chemical mechanism of a cysteine protease, cathepsin C, as revealed by integration of both steady-state and pre-steady-state solvent kinetic isotope effects. Biochemistry 2008; 47:8697-710. [PMID: 18656960 DOI: 10.1021/bi8007627] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cathepsin C, or dipeptidyl peptidase I, is a lysosomal cysteine protease of the papain family that catalyzes the sequential removal of dipeptides from the free N-termini of proteins and peptides. Using the dipeptide substrate Ser-Tyr-AMC, cathepsin C was characterized in both steady-state and pre-steady-state kinetic modes. The pH(D) rate profiles for both log k cat/ K m and log k cat conformed to bell-shaped curves for which an inverse solvent kinetic isotope effect (sKIE) of 0.71 +/- 0.14 for (D)( k cat/ K a) and a normal sKIE of 2.76 +/- 0.03 for (D) k cat were obtained. Pre-steady-state kinetics exhibited a single-exponential burst of AMC formation in which the maximal acylation rate ( k ac = 397 +/- 5 s (-1)) was found to be nearly 30-fold greater than the rate-limiting deacylation rate ( k dac = 13.95 +/- 0.013 s (-1)) and turnover number ( k cat = 13.92 +/- 0.001 s (-1)). Analysis of pre-steady-state burst kinetics in D 2O allowed abstraction of a normal sKIE for the acylation half-reaction that was not observed in steady-state kinetics. Since normal sKIEs were obtained for all measurable acylation steps in the presteady state [ (D) k ac = 1.31 +/- 0.04, and the transient kinetic isotope effect at time zero (tKIE (0)) = 2.3 +/- 0.2], the kinetic step(s) contributing to the inverse sKIE of (D)( k cat/ K a) must occur more rapidly than the experimental time frame of the transient kinetics. Results are consistent with a chemical mechanism in which acylation occurs via a two-step process: the thiolate form of Cys-234, which is enriched in D 2O and gives rise to the inverse value of (D)( k cat/ K a), attacks the substrate to form a tetrahedral intermediate that proceeds to form an acyl-enzyme intermediate during a proton transfer step expressing a normal sKIE. The subsequent deacylation half-reaction is rate-limiting, with proton transfers exhibiting normal sKIEs. Through derivation of 12 equations describing all kinetic parameters and sKIEs for the proposed cathepsin C mechanism, integration of both steady-state and pre-steady-state kinetics with sKIEs allowed the provision of at least one self-consistent set of values for all 13 rate constants in this cysteine protease's chemical mechanism. Simulation of the resulting kinetic profile showed that at steady state approximately 80% of the enzyme exists in an active-site cysteine-acylated form in the mechanistic pathway. The chemical and kinetic details deduced from this work provide a potential roadmap to help steer drug discovery efforts for this and other disease-relevant cysteine proteases.
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Affiliation(s)
- Jessica L Schneck
- Department of Biological Reagents and Assay Development and Discovery Technology Group, GlaxoSmithKline Pharmaceuticals, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426-0989, USA
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Schneck JL, Fried B. Effects of snail size on encystment of Echinostoma caproni in juvenile Biomphalaria glabrata (NMRI strain) and observations on the survival of infected snails. J Helminthol 2007; 78:277-9. [PMID: 15469634 DOI: 10.1079/joh2004235] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
AbstractThe effects of snail size on encystment of Echinostoma caproni cercariae in neonatal and juvenile Biomphalaria glabrata (NMRI strain) snails were studied. Encystment in neonatal (0.7–1.1 mm shell diameter) and juvenile (2–3 mm shell diameter) snails was compared 24 h post-infection (PI) following individual exposure of snails of each size to 1, 5, 10, 25 and 50 cercariae. Significantly more cysts were recovered from juveniles exposed to 1, 5, 10 and 50 cercariae than from neonatals with comparable exposure. Size of B. glabrata was a major factor in determining cyst burden in this planorbid. Survival of infected versus uninfected neonatals and juveniles was also examined for 7 days. Neonatals exposed to 10 cercariae showed a significant decrease in survival at 3, 6 and 7 days PI when compared to the uninfected controls. There was no significant decrease in the survival of juveniles exposed to 10 cercariae compared to uninfected controls at any time point. Snail size was a factor in mortality associated with echinostome cercarial penetration and encystment.
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Affiliation(s)
- J L Schneck
- Department of Biology, Lafayette College, Easton, PA 18042, USA
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Affiliation(s)
- J L Schneck
- Department of Biology, Lafayette College, Easton, PA 18042, USA
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Abstract
Echinostoma caproni tail loss was studied in vitro in the presence of the toxicant copper sulphate (CuSO4) in concentrations ranging from 1 to 10 000 mg l(-1) in standardized artificial spring water (pH 7.4, osmolarity 34 mOsm kg(-1) H2O, Ca(2+) 20 mg l(-1)) at 23 degrees C. Tail loss was also studied in the absence of toxicants during in vivo encystment of the cercariae in juvenile Biomphalaria glabrata. As the concentration of CuSO4 increased, the percentage of cercarial tail loss increased. By 2 h in 10 000 mg l(-1), 1000 mg l(-1) and 100 mg l(-1) CuSO4, 50%, 23% and 13%, respectively, of the cercariae had lost their tails. In the in vivo studies, by 1 h PI, 59+/-5% of cercariae had lost their tails and only 4+/-1% of the cercariae were actively swimming in the multi-well dishes. At 3 h PI, 72+/-3% of the cercariae began to form cysts within the snails.
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Affiliation(s)
- B Fried
- Department of Biology, Lafayette College, Easton, Pennsylvania 18042, USA.
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Abstract
The effects of various concentrations of copper sulphate were studied on in vitro encystment of Echinostoma caproni in a Locke's-artificial spring water (ASW) (1:1) medium. Cercariae were killed in 10,000 mg l(-1) CuSO4 in Locke's-ASW (1:1) within 24 h and extruded cystogenous material to produce an abnormal cyst wall. The 'emergency response' of encystment to high concentrations of copper reported for Parorchis acanthus cercariae did not occur in E. caproni. Concentrations of 1000 mg l(-1) and 100 mg l(-1) CuSO4 in Locke's-ASW (1:1) also killed the cercariae without encystment by 48 h. A concentration of 10 mg l(-1) CuSO4 in Locke's-ASW (1:1) allowed for normal in vitro encystment within 48 h and these cysts were capable of excystation in a trypsin-bile salts medium.
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Affiliation(s)
- B Fried
- Department of Biology, Lafayette College, Easton, Pennsylvania 18042, USA.
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Fried B, Schneck JL, Ponder EL. Effects of tonicity, digestive enzymes and bile salts, and nutrient media on the survival of excysted metacercariae of Echinostoma caproni. Parasitol Res 2004; 93:1-4. [PMID: 15029492 DOI: 10.1007/s00436-004-1091-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2003] [Accepted: 02/06/2004] [Indexed: 11/30/2022]
Abstract
The effects of tonicity, digestive enzymes and bile salts, and various nutrients added to Locke's solution were studied on the chemically excysted metacercariae of Echinostoma caproni. Metacercariae were maintained at 37.5 degrees C in multiwell chambers, ten per 0.5 ml of test solution; each experiment was replicated five times. Most metacercariae maintained in deionized water or Locke's 2x solution were dead within 2 h. About 85% and 55% of the metacercariae were alive at 8 h in Locke's 1x and Locke's 0.5x, respectively. Metacercariae of this species are osmoconformers, as is the case for adult digeneans. All metacercariae were dead in an acid saline or acid pepsin medium by 2 h. About 50% of the metacercariae were alive in an alkaline trypsin-bile salts medium at 4 h. These results suggest that the acidic pepsin environment in the stomach of a definitive host would be detrimental to the survival of excysted metacercariae, but prolonged survival in alkaline trypsin-bile salts would facilitate establishment of this larval stage in the mucosa of the host small intestine. Studies on excysted metacercariae in Locke's 1x supplemented with various nutrients showed that optimal survival occurred in Locke's plus 0.1% glucose and in Locke's 1x plus 1% hen's egg yolk. Significant survival of excysted metacercariae in Locke's 1x supplemented with either 0.1% proline, 0.1% threonine, or 0.1% serine did not occur.
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Affiliation(s)
- Bernard Fried
- Department of Biology, Lafayette College, Easton, PA 18042, USA.
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Schneck JL, Fried B, Sherma J. Effects of tonicity on the release of neutral lipids in Echinostoma caproni adults and observations on lipids in excysted metacercariae. Parasitol Res 2004; 92:285-8. [PMID: 14722759 DOI: 10.1007/s00436-003-1051-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2003] [Accepted: 11/13/2003] [Indexed: 11/30/2022]
Abstract
High performance thin layer chromatography was used to analyze neutral lipids in worm incubates isotonic, hypotonic, and hypertonic to the intestinal habitat of adult Echinostoma caproni. Qualitative analysis revealed the presence of free sterols, free fatty acids, triacylglycerols, and a steryl ester/hydrocarbon fraction in all incubate samples. The most abundant neutral lipid fraction released into the incubation medium was the triacylglycerol fraction. This fraction was quantified after worms were maintained for 2 h at 37.5 degrees C in hypertonic (Locke's 2x solution), isotonic (Locke's 0.5x solution) and hypotonic (deionized water) media. Percentages of triacylglycerols on a wet-weight basis found in Locke's 2x, 0.5x, and deionized water were 0.369, 3.23, and 0.242, respectively, suggesting that the optimal medium to obtain maximal excretory-secretory products is the Locke's 0.5x solution. Histochemical staining of whole excysted metacercariae with oil red O did not detect neutral lipids. Analysis of 500 excysted metacercariae incubated for 2 h at 37.5 degrees C revealed that free sterols, free fatty acids, and triacylglycerols were released in amounts of 16.2, 1.59, and 5.34 ng/organism, respectively. Our results were compared with previous studies on neutral lipids in excysted metacercariae and adults of E. trivolvis. Variations in the results of our study compared with others reflect intrinsic differences in the species of echinostome used.
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