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Zessin M, Meleshin M, Hilscher S, Schiene-Fischer C, Barinka C, Jung M, Schutkowski M. Continuous Fluorescent Sirtuin Activity Assay Based on Fatty Acylated Lysines. Int J Mol Sci 2023; 24:ijms24087416. [PMID: 37108579 PMCID: PMC10138348 DOI: 10.3390/ijms24087416] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/06/2023] [Accepted: 04/10/2023] [Indexed: 04/29/2023] Open
Abstract
Lysine deacetylases, like histone deacetylases (HDACs) and sirtuins (SIRTs), are involved in many regulatory processes such as control of metabolic pathways, DNA repair, and stress responses. Besides robust deacetylase activity, sirtuin isoforms SIRT2 and SIRT3 also show demyristoylase activity. Interestingly, most of the inhibitors described so far for SIRT2 are not active if myristoylated substrates are used. Activity assays with myristoylated substrates are either complex because of coupling to enzymatic reactions or time-consuming because of discontinuous assay formats. Here we describe sirtuin substrates enabling direct recording of fluorescence changes in a continuous format. Fluorescence of the fatty acylated substrate is different when compared to the deacylated peptide product. Additionally, the dynamic range of the assay could be improved by the addition of bovine serum albumin, which binds the fatty acylated substrate and quenches its fluorescence. The main advantage of the developed activity assay is the native myristoyl residue at the lysine side chain avoiding artifacts resulting from the modified fatty acyl residues used so far for direct fluorescence-based assays. Due to the extraordinary kinetic constants of the new substrates (KM values in the low nM range, specificity constants between 175,000 and 697,000 M-1s-1) it was possible to reliably determine the IC50 and Ki values for different inhibitors in the presence of only 50 pM of SIRT2 using different microtiter plate formats.
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Affiliation(s)
- Matthes Zessin
- Department of Medicinal Chemistry, Institute of Pharmacy, Martin-Luther-University Halle-Wittenberg, 06120 Halle, Germany
| | - Marat Meleshin
- Department of Enzymology, Charles Tanford Protein Center, Institute of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, 06120 Halle, Germany
| | - Sebastian Hilscher
- Department of Medicinal Chemistry, Institute of Pharmacy, Martin-Luther-University Halle-Wittenberg, 06120 Halle, Germany
| | - Cordelia Schiene-Fischer
- Department of Enzymology, Charles Tanford Protein Center, Institute of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, 06120 Halle, Germany
| | - Cyril Barinka
- Institute of Biotechnology, Czech Academy of Sciences, BIOCEV, Prumyslova 595, 25250 Vestec, Czech Republic
| | - Manfred Jung
- Institute of Pharmaceutical Sciences, University of Freiburg, Albertstraße 25, 79104 Freiburg, Germany
| | - Mike Schutkowski
- Department of Enzymology, Charles Tanford Protein Center, Institute of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, 06120 Halle, Germany
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2
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Zessin M, Meleshin M, Simic Z, Kalbas D, Arbach M, Gebhardt P, Melesina J, Liebscher S, Bordusa F, Sippl W, Barinka C, Schutkowski M. Continuous Sirtuin/HDAC (histone deacetylase) activity assay using thioamides as PET (Photoinduced Electron Transfer)-based fluorescence quencher. Bioorg Chem 2021; 117:105425. [PMID: 34695733 DOI: 10.1016/j.bioorg.2021.105425] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 10/07/2021] [Accepted: 10/09/2021] [Indexed: 12/28/2022]
Abstract
Histone deacylase 11 and human sirtuins are able to remove fatty acid-derived acyl moieties from the ε-amino group of lysine residues. Specific substrates are needed for investigating the biological functions of these enzymes. Additionally, appropriate screening systems are required for identification of modulators of enzymatic activities of HDAC11 and sirtuins. We designed and synthesized a set of activity probes by incorporation of a thioamide quencher unit into the fatty acid-derived acyl chain and a fluorophore in the peptide sequence. Systematic variation of both fluorophore and quencher position resulted "super-substrates" with catalytic constants of up to 15,000,000 M-1s-1 for human sirtuin 2 (Sirt2) enabling measurements using enzyme concentrations down to 100 pM in microtiter plate-based screening formats. It could be demonstrated that the stalled intermediate formed by the reaction of Sirt2-bound thiomyristoylated peptide and NAD+ has IC50 values below 200 pM.
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Affiliation(s)
- Matthes Zessin
- Department of Medicinal Chemistry, Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Halle/Saale, Germany
| | - Marat Meleshin
- Department of Enzymology, Charles Tanford Protein Center, Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Halle/Saale, Germany
| | - Zeljko Simic
- Department of Enzymology, Charles Tanford Protein Center, Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Halle/Saale, Germany
| | - Diana Kalbas
- Department of Enzymology, Charles Tanford Protein Center, Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Halle/Saale, Germany
| | - Miriam Arbach
- Department of Enzymology, Charles Tanford Protein Center, Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Halle/Saale, Germany
| | - Philip Gebhardt
- Department of Enzymology, Charles Tanford Protein Center, Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Halle/Saale, Germany
| | - Jelena Melesina
- Department of Medicinal Chemistry, Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Halle/Saale, Germany
| | - Sandra Liebscher
- Department of Natural Product Biochemistry, Charles Tanford Protein Center, Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Halle/Saale, Germany
| | - Frank Bordusa
- Department of Natural Product Biochemistry, Charles Tanford Protein Center, Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Halle/Saale, Germany
| | - Wolfgang Sippl
- Department of Medicinal Chemistry, Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Halle/Saale, Germany
| | - Cyril Barinka
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Prumyslova 595, 252 50 Vestec, Czech Republic
| | - Mike Schutkowski
- Department of Enzymology, Charles Tanford Protein Center, Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Halle/Saale, Germany.
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3
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Kutil Z, Mikešová J, Zessin M, Meleshin M, Nováková Z, Alquicer G, Kozikowski A, Sippl W, Bařinka C, Schutkowski M. Continuous Activity Assay for HDAC11 Enabling Reevaluation of HDAC Inhibitors. ACS OMEGA 2019; 4:19895-19904. [PMID: 31788622 PMCID: PMC6882135 DOI: 10.1021/acsomega.9b02808] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 10/18/2019] [Indexed: 05/05/2023]
Abstract
Histone deacetylase 11 (HDAC11) preferentially removes fatty acid residues from lysine side chains in a peptide or protein environment. Here, we report the development and validation of a continuous fluorescence-based activity assay using an internally quenched TNFα-derived peptide derivative as a substrate. The threonine residue in the +1 position was replaced by the quencher amino acid 3'-nitro-l-tyrosine and the fatty acyl moiety substituted by 2-aminobenzoylated 11-aminoundecanoic acid. The resulting peptide substrate enables fluorescence-based direct and continuous readout of HDAC11-mediated amide bond cleavage fully compatible with high-throughput screening formats. The Z'-factor is higher than 0.85 for the 15 μM substrate concentration, and the signal-to-noise ratio exceeds 150 for 384-well plates. In the absence of NAD+, this substrate is specific for HDAC11. Reevaluation of inhibitory data using our novel assay revealed limited potency and selectivity of known HDAC inhibitors, including Elevenostat, a putative HDAC11-specific inhibitor.
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Affiliation(s)
- Zsófia Kutil
- Institute
of Biotechnology of the Czech Academy of Sciences, BIOCEV, Prumyslova 595, 252 50 Vestec, Czech Republic
| | - Jana Mikešová
- Institute
of Biotechnology of the Czech Academy of Sciences, BIOCEV, Prumyslova 595, 252 50 Vestec, Czech Republic
| | - Matthes Zessin
- Department
of Medicinal Chemistry, Institute of Pharmacy, Martin-Luther-University Halle-Wittenberg, 06120 Halle (Saale), Germany
| | - Marat Meleshin
- Department
of Enzymology, Institute of Biochemistry and Biotechnology, Charles
Tanford Protein Centre, Martin Luther University
Halle-Wittenberg, Kurt-Mothes-Straße
3a, 06120 Halle
(Saale), Germany
| | - Zora Nováková
- Institute
of Biotechnology of the Czech Academy of Sciences, BIOCEV, Prumyslova 595, 252 50 Vestec, Czech Republic
| | - Glenda Alquicer
- Institute
of Biotechnology of the Czech Academy of Sciences, BIOCEV, Prumyslova 595, 252 50 Vestec, Czech Republic
| | - Alan Kozikowski
- StarWise
Therapeutics LLC, 505
S Rosa Road, Suite 27, Madison, Wisconsin 53719-1235, United States
| | - Wolfgang Sippl
- Department
of Medicinal Chemistry, Institute of Pharmacy, Martin-Luther-University Halle-Wittenberg, 06120 Halle (Saale), Germany
| | - Cyril Bařinka
- Institute
of Biotechnology of the Czech Academy of Sciences, BIOCEV, Prumyslova 595, 252 50 Vestec, Czech Republic
- E-mail: . Tel.: +420-325-873-777 (C.B.)
| | - Mike Schutkowski
- Department
of Enzymology, Institute of Biochemistry and Biotechnology, Charles
Tanford Protein Centre, Martin Luther University
Halle-Wittenberg, Kurt-Mothes-Straße
3a, 06120 Halle
(Saale), Germany
- E-mail: . Tel.: +49-345-5524-828 (M.S.)
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Zessin M, Kutil Z, Meleshin M, Nováková Z, Ghazy E, Kalbas D, Marek M, Romier C, Sippl W, Bařinka C, Schutkowski M. One-Atom Substitution Enables Direct and Continuous Monitoring of Histone Deacylase Activity. Biochemistry 2019; 58:4777-4789. [PMID: 31682411 DOI: 10.1021/acs.biochem.9b00786] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We developed a one-step direct assay for the determination of histone deacylase (HDAC) activity by substituting the carbonyl oxygen of the acyl moiety with sulfur, resulting in thioacylated lysine side chains. This modification is recognized by class I HDACs with different efficiencies ranging from not accepted for HDAC1 to kinetic constants similar to that of the parent oxo substrate for HDAC8. Class II HDACs can hydrolyze thioacylated substrates with approximately 5-10-fold reduced kcat values, which resembles the effect of thioamide substitution in metallo-protease substrates. Class IV HDAC11 accepts thiomyristoyl modification less efficiently with an ∼5-fold reduced specificity constant. On the basis of the unique spectroscopic properties of thioamide bonds (strong absorption in spectral range of 260-280 nm and efficient fluorescence quenching), HDAC-mediated cleavage of thioamides could be followed by ultraviolet-visible and fluorescence spectroscopy in a continuous manner. The HDAC activity assay is compatible with microtiter plate-based screening formats up to 1536-well plates with Z' factors of >0.75 and signal-to-noise ratios of >50. Using thioacylated lysine residues in p53-derived peptides, we optimized substrates for HDAC8 with a catalytic efficiency of >250000 M-1 s-1, which are more than 100-fold more effective than most of the known substrates. We determined inhibition constants of several inhibitors for human HDACs using thioacylated peptidic substrates and found good correlation with the values from the literature. On the other hand, we could introduce N-methylated, N-acylated lysine residues as inhibitors for HDACs with an IC50 value of 1 μM for an N-methylated, N-myristoylated peptide derivative and human HDAC11.
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Affiliation(s)
- Matthes Zessin
- Department of Medicinal Chemistry, Institute of Pharmacy , Martin-Luther-University Halle-Wittenberg , 06120 Halle/Saale , Germany
| | - Zsófia Kutil
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV , Prumyslova 595 , 252 50 Vestec , Czech Republic
| | - Marat Meleshin
- Department of Enzymology, Institute of Biochemistry and Biotechnology, Charles-Tanford-Protein Center , Martin-Luther-University Halle-Wittenberg , 06120 Halle/Saale , Germany
| | - Zora Nováková
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV , Prumyslova 595 , 252 50 Vestec , Czech Republic
| | - Ehab Ghazy
- Department of Medicinal Chemistry, Institute of Pharmacy , Martin-Luther-University Halle-Wittenberg , 06120 Halle/Saale , Germany
| | - Diana Kalbas
- Department of Enzymology, Institute of Biochemistry and Biotechnology, Charles-Tanford-Protein Center , Martin-Luther-University Halle-Wittenberg , 06120 Halle/Saale , Germany
| | - Martin Marek
- Departement de Biologie Structurale Integrative, Institut de Genetique et Biologie Moleculaire et Cellulaire (IGBMC) , Universite de Strasbourg (UDS), CNRS, INSERM , 1 rue Laurent Fries, B.P. 10142 , 67404 Illkirch Cedex IGBMC, France
| | - Christophe Romier
- Departement de Biologie Structurale Integrative, Institut de Genetique et Biologie Moleculaire et Cellulaire (IGBMC) , Universite de Strasbourg (UDS), CNRS, INSERM , 1 rue Laurent Fries, B.P. 10142 , 67404 Illkirch Cedex IGBMC, France
| | - Wolfgang Sippl
- Department of Medicinal Chemistry, Institute of Pharmacy , Martin-Luther-University Halle-Wittenberg , 06120 Halle/Saale , Germany
| | - Cyril Bařinka
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV , Prumyslova 595 , 252 50 Vestec , Czech Republic
| | - Mike Schutkowski
- Department of Enzymology, Institute of Biochemistry and Biotechnology, Charles-Tanford-Protein Center , Martin-Luther-University Halle-Wittenberg , 06120 Halle/Saale , Germany
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Delman M, Avcı ST, Akçok İ, Kanbur T, Erdal E, Çağır A. Antiproliferative activity of (R)-4'-methylklavuzon on hepatocellular carcinoma cells and EpCAM +/CD133 + cancer stem cells via SIRT1 and Exportin-1 (CRM1) inhibition. Eur J Med Chem 2019; 180:224-237. [PMID: 31306909 DOI: 10.1016/j.ejmech.2019.07.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 07/07/2019] [Accepted: 07/08/2019] [Indexed: 12/12/2022]
Abstract
Cytotoxic effects of (R)-4'-methylklavuzon were investigated on hepatocellular carcinoma cells (HuH-7 and HepG2) and HuH-7 EpCAM+/CD133+ cancer stem cells. IC50 of (R)-4'-methylklavuzon was found as 1.25 μM for HuH-7 parental cells while it was found as 2.50 μM for HuH-7 EpCAM+/CD133+ cancer stem cells. (R)-4'-methylklavuzon tended to show more efficient in vitro cytotoxicity with its lower IC50 values on hepatocellular carcinoma cell lines compared to its lead molecule, goniothalamin and FDA-approved drugs, sorafenib and regorafenib. Cell-based Sirtuin/HDAC enzyme activity measurements revealed that endogenous Sirtuin/HDAC enzymes were reduced by 40% compared to control. SIRT1 protein levels were upregulated indicating triggered DNA repair mechanism. p53 was overexpressed in HepG2 cells. (R)-4'-methylklavuzon inhibited CRM1 protein providing increased retention of p53 and RIOK2 protein in the nucleus. HuH-7 parental and EpCAM+/CD133+ cancer stem cell spheroids lost intact morphology. 3D HepG2 spheroid viabilities were decreased in a correlation with upregulation in p53 protein levels.
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Affiliation(s)
- Murat Delman
- Department of Biotechnology and Bioengineering, Izmir Institute of Technology, 35430, Urla, Izmir, Turkey
| | - Sanem Tercan Avcı
- Izmir Biomedicine and Genome Center, 35340, Balcova, Izmir, Turkey; Department of Medical Biology and Genetics, Faculty of Medicine, Dokuz Eylul University, 35340, Balcova, Izmir, Turkey
| | - İsmail Akçok
- Department of Chemistry, Faculty of Science, Izmir Institute of Technology, 35430, Urla, Izmir, Turkey
| | - Tuğçe Kanbur
- Department of Chemistry, Faculty of Science, Izmir Institute of Technology, 35430, Urla, Izmir, Turkey
| | - Esra Erdal
- Izmir Biomedicine and Genome Center, 35340, Balcova, Izmir, Turkey; Department of Medical Biology and Genetics, Faculty of Medicine, Dokuz Eylul University, 35340, Balcova, Izmir, Turkey.
| | - Ali Çağır
- Department of Chemistry, Faculty of Science, Izmir Institute of Technology, 35430, Urla, Izmir, Turkey.
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6
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Hartl M, Füßl M, Boersema PJ, Jost JO, Kramer K, Bakirbas A, Sindlinger J, Plöchinger M, Leister D, Uhrig G, Moorhead GB, Cox J, Salvucci ME, Schwarzer D, Mann M, Finkemeier I. Lysine acetylome profiling uncovers novel histone deacetylase substrate proteins in Arabidopsis. Mol Syst Biol 2017; 13:949. [PMID: 29061669 PMCID: PMC5658702 DOI: 10.15252/msb.20177819] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Histone deacetylases have central functions in regulating stress defenses and development in plants. However, the knowledge about the deacetylase functions is largely limited to histones, although these enzymes were found in diverse subcellular compartments. In this study, we determined the proteome‐wide signatures of the RPD3/HDA1 class of histone deacetylases in Arabidopsis. Relative quantification of the changes in the lysine acetylation levels was determined on a proteome‐wide scale after treatment of Arabidopsis leaves with deacetylase inhibitors apicidin and trichostatin A. We identified 91 new acetylated candidate proteins other than histones, which are potential substrates of the RPD3/HDA1‐like histone deacetylases in Arabidopsis, of which at least 30 of these proteins function in nucleic acid binding. Furthermore, our analysis revealed that histone deacetylase 14 (HDA14) is the first organellar‐localized RPD3/HDA1 class protein found to reside in the chloroplasts and that the majority of its protein targets have functions in photosynthesis. Finally, the analysis of HDA14 loss‐of‐function mutants revealed that the activation state of RuBisCO is controlled by lysine acetylation of RuBisCO activase under low‐light conditions.
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Affiliation(s)
- Markus Hartl
- Plant Proteomics, Max Planck Institute for Plant Breeding Research, Cologne, Germany.,Plant Molecular Biology, Department Biology I, Ludwig-Maximilians-University Munich, Martinsried, Germany.,Mass Spectrometry Facility, Max F. Perutz Laboratories (MFPL), Vienna Biocenter (VBC), University of Vienna, Vienna, Austria
| | - Magdalena Füßl
- Plant Proteomics, Max Planck Institute for Plant Breeding Research, Cologne, Germany.,Plant Molecular Biology, Department Biology I, Ludwig-Maximilians-University Munich, Martinsried, Germany.,Plant Physiology, Institute of Plant Biology and Biotechnology, University of Muenster, Muenster, Germany
| | - Paul J Boersema
- Proteomics and Signal Transduction, Max-Planck Institute of Biochemistry, Martinsried, Germany
| | - Jan-Oliver Jost
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Katharina Kramer
- Plant Proteomics, Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Ahmet Bakirbas
- Plant Proteomics, Max Planck Institute for Plant Breeding Research, Cologne, Germany.,Plant Physiology, Institute of Plant Biology and Biotechnology, University of Muenster, Muenster, Germany
| | - Julia Sindlinger
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Magdalena Plöchinger
- Plant Molecular Biology, Department Biology I, Ludwig-Maximilians-University Munich, Martinsried, Germany
| | - Dario Leister
- Plant Molecular Biology, Department Biology I, Ludwig-Maximilians-University Munich, Martinsried, Germany
| | - Glen Uhrig
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Greg Bg Moorhead
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Jürgen Cox
- Proteomics and Signal Transduction, Max-Planck Institute of Biochemistry, Martinsried, Germany
| | - Michael E Salvucci
- US Department of Agriculture, Agricultural Research Service, Arid-Land Agricultural Research Center, Maricopa, AZ, USA
| | - Dirk Schwarzer
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Matthias Mann
- Proteomics and Signal Transduction, Max-Planck Institute of Biochemistry, Martinsried, Germany
| | - Iris Finkemeier
- Plant Proteomics, Max Planck Institute for Plant Breeding Research, Cologne, Germany .,Plant Molecular Biology, Department Biology I, Ludwig-Maximilians-University Munich, Martinsried, Germany.,Plant Physiology, Institute of Plant Biology and Biotechnology, University of Muenster, Muenster, Germany
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7
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Jost JO, Hanswillemenke A, Schwarzer D. A miniaturized readout strategy for endogenous histone deacetylase activity. MOLECULAR BIOSYSTEMS 2016; 11:1820-3. [PMID: 26009008 DOI: 10.1039/c5mb00326a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Histone deacetylases are important drug targets, which are difficult to characterize due to their poor accessibility. We have developed a miniaturized assay for the multi-site readout of deacetylase activity and profiled the substrate selectivity of HDACs for acetylation sites on histone H4 and tumor suppressor protein p53.
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Affiliation(s)
- Jan Oliver Jost
- Interfaculty Institute of Biochemistry, University of Tuebingen, Hoppe-Seyler-Str. 4, 72076 Tuebingen, Germany.
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8
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Li P, Han Y, Li Y, Zhu R, Wang H, Nie Z, Yao S. Bioanalytical approaches for the detection of protein acetylation-related enzymes. Anal Bioanal Chem 2016; 408:2659-68. [DOI: 10.1007/s00216-016-9304-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 11/26/2015] [Accepted: 01/04/2016] [Indexed: 10/22/2022]
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