1
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Illes-Toth E, Stubbs CJ, Sisley EK, Bellamy-Carter J, Simmonds AL, Mize TH, Styles IB, Goodwin RJA, Cooper HJ. Quantitative Characterization of Three Carbonic Anhydrase Inhibitors by LESA Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2022; 33:1168-1175. [PMID: 35675480 PMCID: PMC9264382 DOI: 10.1021/jasms.2c00024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Liquid extraction surface analysis (LESA) coupled to native mass spectrometry (MS) presents unique analytical opportunities due to its sensitivity, speed, and automation. Here, we examine whether this tool can be used to quantitatively probe protein-ligand interactions through calculation of equilibrium dissociation constants (Kd values). We performed native LESA MS analyses for a well-characterized system comprising bovine carbonic anhydrase II and the ligands chlorothiazide, dansylamide, and sulfanilamide, and compared the results with those obtained from direct infusion mass spectrometry and surface plasmon resonance measurements. Two LESA approaches were considered: In one approach, the protein and ligand were premixed in solution before being deposited and dried onto a solid substrate for LESA sampling, and in the second, the protein alone was dried onto the substrate and the ligand was included in the LESA sampling solvent. Good agreement was found between the Kd values derived from direct infusion MS and LESA MS when the protein and ligand were premixed; however, Kd values determined from LESA MS measurements where the ligand was in the sampling solvent were inconsistent. Our results suggest that LESA MS is a suitable tool for quantitative analysis of protein-ligand interactions when the dried sample comprises both protein and ligand.
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Affiliation(s)
- Eva Illes-Toth
- School
of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Christopher J. Stubbs
- Mechanistic
and Structural Biology, Discovery Sciences,
R&D, AstraZeneca, Cambridge CB4 0WG, United Kingdom
| | - Emma K. Sisley
- School
of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | | | - Anna L. Simmonds
- School
of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Todd H. Mize
- School
of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Iain B. Styles
- School
of Computer Science and Centre of Membrane Proteins and Receptors
(COMPARE), University of Birmingham, Birmingham B15 2TT, United Kingdom
- The Alan Turing Institute, London NW1 2DB, United Kingdom
- University of Nottingham, Midlands NG7 2RD, United Kingdom
| | - Richard J. A. Goodwin
- Imaging and
Data Analytics, Clinical Pharmacology & Safety Sciences, BioPharmaceuticals
R&D, AstraZeneca, Cambridge CB4 0WG, United Kingdom
| | - Helen J. Cooper
- School
of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
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2
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Frutiger A, Gatterdam K, Blickenstorfer Y, Reichmuth AM, Fattinger C, Vörös J. Ultra Stable Molecular Sensors by Submicron Referencing and Why They Should Be Interrogated by Optical Diffraction-Part II. Experimental Demonstration. SENSORS (BASEL, SWITZERLAND) 2020; 21:E9. [PMID: 33375003 PMCID: PMC7792590 DOI: 10.3390/s21010009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 12/07/2020] [Accepted: 12/08/2020] [Indexed: 12/12/2022]
Abstract
Label-free optical biosensors are an invaluable tool for molecular interaction analysis. Over the past 30 years, refractometric biosensors and, in particular, surface plasmon resonance have matured to the de facto standard of this field despite a significant cross reactivity to environmental and experimental noise sources. In this paper, we demonstrate that sensors that apply the spatial affinity lock-in principle (part I) and perform readout by diffraction overcome the drawbacks of established refractometric biosensors. We show this with a direct comparison of the cover refractive index jump sensitivity as well as the surface mass resolution of an unstabilized diffractometric biosensor with a state-of-the-art Biacore 8k. A combined refractometric diffractometric biosensor demonstrates that a refractometric sensor requires a much higher measurement precision than the diffractometric to achieve the same resolution. In a conceptual and quantitative discussion, we elucidate the physical reasons behind and define the figure of merit of diffractometric biosensors. Because low-precision unstabilized diffractometric devices achieve the same resolution as bulky stabilized refractometric sensors, we believe that label-free optical sensors might soon move beyond the drug discovery lab as miniaturized, mass-produced environmental/medical sensors. In fact, combined with the right surface chemistry and recognition element, they might even bring the senses of smell/taste to our smart devices.
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Affiliation(s)
- Andreas Frutiger
- Laboratory of Biosensors and Bioelectronics, Institute for Biomedical Engineering, University and ETH Zürich, 8092 Zürich, Switzerland; (A.F.); (Y.B.); (A.M.R.)
| | - Karl Gatterdam
- Institute of Structural Biology, University Hospital Bonn, University of Bonn, 53127 Bonn, Germany;
| | - Yves Blickenstorfer
- Laboratory of Biosensors and Bioelectronics, Institute for Biomedical Engineering, University and ETH Zürich, 8092 Zürich, Switzerland; (A.F.); (Y.B.); (A.M.R.)
| | - Andreas Michael Reichmuth
- Laboratory of Biosensors and Bioelectronics, Institute for Biomedical Engineering, University and ETH Zürich, 8092 Zürich, Switzerland; (A.F.); (Y.B.); (A.M.R.)
| | - Christof Fattinger
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, 4070 Basel, Switzerland
| | - János Vörös
- Laboratory of Biosensors and Bioelectronics, Institute for Biomedical Engineering, University and ETH Zürich, 8092 Zürich, Switzerland; (A.F.); (Y.B.); (A.M.R.)
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3
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Kammer MN, Kussrow AK, Olmsted IR, Bornhop DJ. A Highly Compensated Interferometer for Biochemical Analysis. ACS Sens 2018; 3:1546-1552. [PMID: 29984991 DOI: 10.1021/acssensors.8b00361] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Here we report an improved interferometric sensing approach that facilitates high sensitivity nanovolume refractive index (RI) measurements and molecular interaction assays without a temperature controller. The compensated backscattering interferometer (CBSI) is based on a helium-neon (He-Ne) laser, a microfluidic chip, and a CCD array. The CBSI enables simultaneous differential RI measurements within nanoliter volumes, at a compensation level of ca. 5 × 10-8 RIU in the presence of large thermal perturbations (8 °C). This level of d n/d T compensation is enabled by elongating the laser beam along the central axis of the microfluidic channel and measuring the difference in positional shift of interference patterns from two adjacent regions of the channel. By separating two solutions by an air gap or oil droplet, CBSI can discriminate the difference in RI for the sample and reference at a detection limit of 7 × 10-7 RIU in the absence of electronic filtering. At this level of ΔRI sensitivity, it is possible to perform label-free, free-solution biochemical assays at the 10s of nM level without the typical high-resolution temperature control needed in conventional interferometers. Here we illustrate the effective use of CBSI by quantifying the binding affinities for mannose-concanavalin A and Ca2+-recoverin interactions.
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Affiliation(s)
- Michael N. Kammer
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235, United States
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Amanda K. Kussrow
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Ian R. Olmsted
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Darryl J. Bornhop
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235, United States
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4
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Kammer MN, Kussrow AK, Bornhop DJ. Longitudinal pixel averaging for improved compensation in backscattering interferometry. OPTICS LETTERS 2018; 43:482-485. [PMID: 29400820 DOI: 10.1364/ol.43.000482] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 12/19/2017] [Indexed: 06/07/2023]
Abstract
Longitudinal averaging of the interference pattern in a compensated backscattering interferometer provides improved compensation for temperature induced refractive index perturbations. Fringe pattern likeness between two discrete detection regions of an off-the-shelf microfluidic chip illuminated by an inexpensive diode laser scales with interrogation length. Averaging the intensity distribution along a 2.75 mm length of the channel results in a 750-fold reduction in sensitivity to temperature and a baseline noise level of 3×10-8 refractive index units (RIU). These observations enable nanoliter-volume interferometric measurements at a level of 10-7 RIU in the presence of a 2°C temperature variation without the need for temperature control.
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5
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Schaefer AK, Melnyk JE, Baksh MM, Lazor KM, Finn MG, Grimes CL. Membrane Association Dictates Ligand Specificity for the Innate Immune Receptor NOD2. ACS Chem Biol 2017; 12:2216-2224. [PMID: 28708377 PMCID: PMC5569645 DOI: 10.1021/acschembio.7b00469] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
![]()
The
human gut must regulate its immune response to resident and
pathogenic bacteria, numbering in the trillions. The peptidoglycan
component of the bacterial cell wall is a dense and rigid structure
that consists of polymeric carbohydrates and highly cross-linked peptides
which offers protection from the host and surrounding environment.
Nucleotide-binding oligomerization domain-containing protein 2 (NOD2),
a human membrane-associated innate immune receptor found in the gut
epithelium and mutated in an estimated 30% of Crohn’s disease
patients, binds to peptidoglycan fragments and initiates an immune
response. Using a combination of chemical synthesis, advanced analytical
assays, and protein biochemistry, we tested the binding of a variety
of synthetic peptidoglycan fragments to wild-type (WT)-NOD2. Only
when the protein was presented in the native membrane did binding
measurements correlate with a NOD2-dependent nuclear factor kappa-light-chain-enhancer
of activated B cells (NF-κB) response, supporting the hypothesis
that the native-membrane environment confers ligand specificity to
the NOD2 receptor for NF-κB signaling. While N-acetyl-muramyl dipeptide (MDP) has been thought to be the minimal
peptidoglycan fragment necessary to activate a NOD2-dependent immune
response, we found that fragments with and without the dipeptide moiety
are capable of binding and activating a NOD2-dependent
NF-κB response, suggesting that the carbohydrate moiety of the
peptidoglycan fragments is the minimal functional epitope. This work
highlights the necessity of studying NOD2-ligand binding in systems
that resemble the receptor’s natural environment, as the cellular
membrane and/or NOD2 interacting partners appear to play a crucial
role in ligand binding and in triggering an innate immune response.
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Affiliation(s)
- Amy K. Schaefer
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - James E. Melnyk
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Michael M. Baksh
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Klare M. Lazor
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - M. G. Finn
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Catherine Leimkuhler Grimes
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
- Department of Biological Sciences, University of Delaware, Newark, Delaware 19716, United States
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6
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Chauhan P, Bora P, Ravikumar G, Jos S, Chakrapani H. Esterase Activated Carbonyl Sulfide/Hydrogen Sulfide (H 2S) Donors. Org Lett 2016; 19:62-65. [PMID: 27996277 DOI: 10.1021/acs.orglett.6b03336] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Hydrogen sulfide (H2S) is a mediator of a number of cellular processes, and modulating cellular levels of this gas has emerged as an important therapeutic area. Localized generation of H2S is thus very useful but highly challenging. Here, we report pivaloyloxymethyl-based carbonothioates and carbamothioates that are activated by the enzyme, esterase, to generate carbonyl sulfide (COS), which is hydrolyzed to H2S.
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Affiliation(s)
- Preeti Chauhan
- Department of Chemistry, Indian Institute of Science Education and Research Pune , Dr. Homi Bhabha Road, Pashan Pune 411 008, Maharashtra, India
| | - Prerona Bora
- Department of Chemistry, Indian Institute of Science Education and Research Pune , Dr. Homi Bhabha Road, Pashan Pune 411 008, Maharashtra, India
| | - Govindan Ravikumar
- Department of Chemistry, Indian Institute of Science Education and Research Pune , Dr. Homi Bhabha Road, Pashan Pune 411 008, Maharashtra, India
| | - Swetha Jos
- Department of Chemistry, Indian Institute of Science Education and Research Pune , Dr. Homi Bhabha Road, Pashan Pune 411 008, Maharashtra, India
| | - Harinath Chakrapani
- Department of Chemistry, Indian Institute of Science Education and Research Pune , Dr. Homi Bhabha Road, Pashan Pune 411 008, Maharashtra, India
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7
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Powell CR, Foster JC, Okyere B, Theus MH, Matson JB. Therapeutic Delivery of H 2S via COS: Small Molecule and Polymeric Donors with Benign Byproducts. J Am Chem Soc 2016; 138:13477-13480. [PMID: 27715026 PMCID: PMC5074078 DOI: 10.1021/jacs.6b07204] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
![]()
Carbonyl
sulfide (COS) is a gas that may play important roles in mammalian
and bacterial biology, but its study is limited by a lack of suitable
donor molecules. We report here the use of N-thiocarboxyanhydrides
(NTAs) as COS donors that release the gas in a sustained manner under
biologically relevant conditions with innocuous peptide byproducts.
Carbonic anhydrase converts COS into H2S, allowing NTAs
to serve as either COS or H2S donors, depending on the
availability of the enzyme. Analysis of the pseudo-first-order H2S release rate under biologically relevant conditions revealed
a release half-life of 75 min for the small molecule NTA under investigation.
A polynorbornene bearing pendant NTAs made by ring-opening metathesis
polymerization was also synthesized to generate a polymeric COS/H2S donor. A half-life of 280 min was measured for the polymeric
donor. Endothelial cell proliferation studies revealed an enhanced
rate of proliferation for cells treated with the NTA over untreated
controls.
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Affiliation(s)
- Chadwick R Powell
- Department of Chemistry, Virginia Tech , Blacksburg, Virginia 24061, United States.,Macromolecules Innovation Institute, Virginia Tech , Blacksburg, Virginia 24061, United States
| | - Jeffrey C Foster
- Department of Chemistry, Virginia Tech , Blacksburg, Virginia 24061, United States.,Macromolecules Innovation Institute, Virginia Tech , Blacksburg, Virginia 24061, United States
| | - Benjamin Okyere
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine , Duck Pond Drive, Blacksburg, Virginia 24061, United States
| | - Michelle H Theus
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine , Duck Pond Drive, Blacksburg, Virginia 24061, United States
| | - John B Matson
- Department of Chemistry, Virginia Tech , Blacksburg, Virginia 24061, United States.,Macromolecules Innovation Institute, Virginia Tech , Blacksburg, Virginia 24061, United States
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8
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Jepsen ST, Jørgensen TM, Zong W, Trydal T, Kristensen SR, Sørensen HS. Evaluation of back scatter interferometry, a method for detecting protein binding in solution. Analyst 2015; 140:895-901. [PMID: 25503796 DOI: 10.1039/c4an01129e] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Back Scatter Interferometry (BSI) has been proposed to be a highly sensitive and versatile refractive index sensor usable for analytical detection of biomarker and protein interactions in solution. However the existing literature on BSI lacks a physical explanation of why protein interactions in general should contribute to the BSI signal. We have established a BSI system to investigate this subject in further detail. We contribute with a thorough analysis of the robustness of the sensor including unwanted contributions to the interferometric signal caused by temperature variation and dissolved gasses. We report a limit of the effective minimum detectability of refractive index at the 10(-7) level. Long term stability was examined by simultaneously monitoring the temperature inside the capillary revealing an average drift of 2.0 × 10(-7) per hour. Finally we show that measurements on protein A incubated with immunoglobulin G do not result in a signal that can be attributed to binding affinities as otherwise claimed in literature.
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Affiliation(s)
- S T Jepsen
- Dept. of Clinical Biochemistry, Aalborg University Hospital, Hobrovej 18-22, 9000 Aalborg, Denmark
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9
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Haddad GL, Young SC, Heindel ND, Bornhop DJ, Flowers RA. Back-Scattering Interferometry: An Ultrasensitive Method for the Unperturbed Detection of Acetylcholinesterase-Inhibitor Interactions. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201203640] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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10
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Haddad GL, Young SC, Heindel ND, Bornhop DJ, Flowers RA. Back-scattering interferometry: an ultrasensitive method for the unperturbed detection of acetylcholinesterase-inhibitor interactions. Angew Chem Int Ed Engl 2012; 51:11126-30. [PMID: 23037915 DOI: 10.1002/anie.201203640] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Revised: 08/24/2012] [Indexed: 11/12/2022]
Abstract
A series of inhibitors of acetylcholinesterase (AChE) have been screened by back-scattering interferometry (BSI). Enzyme levels as low as 100 pM (22,000 molecules of AChE) can be detected. This method can be used to screen for mixed AChE inhibitors, agents that have shown high efficacy against Alzheimer's disease, by detecting dual-binding interactions. E = enzyme, I = inhibitor, S = substrate.
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11
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Fang Y. Ligand-receptor interaction platforms and their applications for drug discovery. Expert Opin Drug Discov 2012; 7:969-88. [PMID: 22860803 DOI: 10.1517/17460441.2012.715631] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
INTRODUCTION The study of drug-target interactions is essential for the understanding of biological processes and for the efforts to develop new therapeutic molecules. Increased ligand-binding assays have coincided with the advances in reagents, detection and instrumentation technologies, the expansion in therapeutic targets of interest, and the increasingly recognized importance of biochemical aspects of drug-target interactions in determining the clinical performance of drug molecules. Nowadays, ligand-binding assays can determine every aspect of many drug-target interactions. AREAS COVERED Given that ligand-target interactions are very diverse, the author has decided to focus on the binding of small molecules to protein targets. This article first reviews the key biochemical aspects of drug-target interactions, and then discusses the detection principles of various ligand-binding techniques in the context of their primary applications for drug discovery and development. EXPERT OPINION Equilibrium-binding affinity should not be used as a solo indicator for the in vivo pharmacology of drugs. The clinical relevance of drug-binding kinetics demands high throughput kinetics early in drug discovery. The dependence of ligand binding and function on the conformation of targets necessitates solution-based and whole cell-based ligand-binding assays. The increasing need to examine ligand binding at the proteome level, driven by the clinical importance of the polypharmacology of ligands, has started to make the structure-based in silico binding screen an indispensable technique for drug discovery and development. Integration of different ligand-binding assays is important to improve the efficiency of the drug discovery and development process.
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Affiliation(s)
- Ye Fang
- Biochemical Technologies, Science and Technology Division, Corning, Inc., Corning, NY 14831, USA.
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12
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Kussrow A, Enders CS, Bornhop DJ. Interferometric methods for label-free molecular interaction studies. Anal Chem 2012; 84:779-92. [PMID: 22060037 PMCID: PMC4317347 DOI: 10.1021/ac202812h] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Amanda Kussrow
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, 7330 Stevenson Center, Nashville, Tennessee 37235, United States
| | - Carolyn S. Enders
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, 7330 Stevenson Center, Nashville, Tennessee 37235, United States
| | - Darryl J. Bornhop
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, 7330 Stevenson Center, Nashville, Tennessee 37235, United States
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13
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Luka Z, Moss F, Loukachevitch LV, Bornhop DJ, Wagner C. Histone demethylase LSD1 is a folate-binding protein. Biochemistry 2011; 50:4750-6. [PMID: 21510664 DOI: 10.1021/bi200247b] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Methylation of lysine residues in histones has been known to serve a regulatory role in gene expression. Although enzymatic removal of the methyl groups was discovered as early as 1973, the enzymes responsible for their removal were isolated and their mechanism of action was described only recently. The first enzyme to show such activity was LSD1, a flavin-containing enzyme that removes the methyl groups from lysines 4 and 9 of histone 3 with the generation of formaldehyde from the methyl group. This reaction is similar to the previously described demethylation reactions conducted by the enzymes dimethylglycine dehydrogenase and sarcosine dehydrogenase, in which protein-bound tetrahydrofolate serves as an accepter of the formaldehyde that is generated. We now show that nuclear extracts of HeLa cells contain LSD1 that is associated with folate. Using the method of back-scattering interferometry, we have measured the binding of various forms of folate to both full-length LSD1 and a truncated form of LSD1 in free solution. The 6R,S form of the natural pentaglutamate form of tetrahydrofolate bound with the highest affinity (K(d) = 2.8 μM) to full-length LSD1. The fact that folate participates in the enzymatic demethylation of histones provides an opportunity for this micronutrient to play a role in the epigenetic control of gene expression.
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Affiliation(s)
- Zigmund Luka
- Department of Biochemistry, Vanderbilt University Medical Center, Nashville, TN 37232, USA
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