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Taylor EM. NTD Diagnostics for Disease Elimination: A Review. Diagnostics (Basel) 2020; 10:E375. [PMID: 32517108 PMCID: PMC7344624 DOI: 10.3390/diagnostics10060375] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 05/07/2020] [Accepted: 06/02/2020] [Indexed: 11/16/2022] Open
Abstract
Neglected Tropical Diseases (NTDs) marked out for disease elimination provide a lens through which to explore the changing status of diagnosis in global health. This paper reports on the findings of a scoping review, which set out to explore the main debates around diagnosis for the elimination of NTDs, including the multiple roles diagnostic technologies are being ascribed and the ideal characteristics of tests. It also attempts to summarise the state of diagnosis for three NTDs with elimination goals. The review places special emphasis on point-of-care testing in acknowledgement of the remote and underserved areas where NTDs proliferate. Early NTD campaigns were largely focused on attack phase planning, whereby a similar set of interventions could be transplanted anywhere. Now, with elimination goals in sight, strategies must be tailored to local settings if they are to attain and sustain success. Diagnostic data helps with local adaptation and is increasingly used for programmatic decision-making. The review finds that elimination goals reframe whom diagnosis is for and the myriad roles diagnostics can play. The exigencies of elimination also serve to highlight deficiencies in the current diagnostic arsenal and development pipeline for many NTDs. Moving forward, a guiding framework is needed to drive research and stimulate investment in diagnosis to support NTD goals.
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Affiliation(s)
- Emma Michelle Taylor
- Department of Social Anthropology, University of Edinburgh, Edinburgh EH8 9LD, UK
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2
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Guo P, Farahat AA, Paul A, Kumar A, Boykin DW, Wilson WD. Extending the σ-Hole Motif for Sequence-Specific Recognition of the DNA Minor Groove. Biochemistry 2020; 59:1756-1768. [PMID: 32293884 DOI: 10.1021/acs.biochem.0c00090] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The majority of current drugs against diseases, such as cancer, can bind to one or more sites in a protein and inhibit its activity. There are, however, well-known limits on the number of druggable proteins, and complementary current drugs with compounds that could selectively target DNA or RNA would greatly enhance the availability of cellular probes and therapeutic progress. We are focusing on the design of sequence-specific DNA minor groove binders that, for example, target the promoter sites of transcription factors involved in a disease. We have started with AT-specific minor groove binders that are known to enter human cells and have entered clinical trials. To broaden the sequence-specific recognition of these compounds, several modules that have H-bond acceptors that strongly and specifically recognize G·C base pairs were identified. A lead module is a thiophene-N-alkyl-benzimidazole σ-hole-based system with terminal phenyl-amidines that have excellent affinity and selectivity for a G·C base pair in the minor groove. Efforts are now focused on optimizing this module. In this work, we are evaluating modifications to the compound aromatic system with the goal of improving GC selectivity and affinity. The lead compounds retain the thiophene-N-alkyl-BI module but have halogen substituents adjacent to an amidine group on the terminal phenyl-amidine. The optimum compounds must have strong affinity and specificity with a residence time of at least 100 s.
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Affiliation(s)
- Pu Guo
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, 50 Decatur Street Southeast, Atlanta, Georgia 30303, United States
| | - Abdelbasset A Farahat
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, 50 Decatur Street Southeast, Atlanta, Georgia 30303, United States.,Master of Pharmaceutical Sciences Program, California Northstate University, 9700 West Taron Drive, Elk Grove, California 95757, United States
| | - Ananya Paul
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, 50 Decatur Street Southeast, Atlanta, Georgia 30303, United States
| | - Arvind Kumar
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, 50 Decatur Street Southeast, Atlanta, Georgia 30303, United States
| | - David W Boykin
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, 50 Decatur Street Southeast, Atlanta, Georgia 30303, United States
| | - W David Wilson
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, 50 Decatur Street Southeast, Atlanta, Georgia 30303, United States
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Farahat AA, Guo P, Shoeib H, Paul A, Boykin DW, Wilson WD. Small Sequence-Sensitive Compounds for Specific Recognition of the G⋅C Base Pair in DNA Minor Groove. Chemistry 2020; 26:4539-4551. [PMID: 31884714 PMCID: PMC7265973 DOI: 10.1002/chem.201904396] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 11/10/2019] [Indexed: 12/24/2022]
Abstract
A series of small diamidines with thiophene and modified N-alkylbenzimidazole σ-hole module represent specific binding to single G⋅C base pair (bp) DNA sequence. The variation of N-alkyl or aromatic rings were sensitive to microstructures of the DNA minor groove. Thirteen new compounds were synthesized to test their binding affinity and selectivity. The dicyanobenzimidazoles needed to synthesize the target diamidines were made via condensation/cyclization reactions of different aldehydes with different 3-amino-4-(alkyl- or phenyl-amino) benzonitriles. The final diamidines were synthesized using lithium bis-trimethylsilylamide (LiN[Si(CH3 )3 ]2 ) or Pinner methods. The newly synthesized compounds showed strong binding and selectivity to AAAGTTT compared to similar sequences AAATTT and AAAGCTTT investigated by several biophysical methods including biosensor-SPR, fluorescence spectroscopy, DNA thermal melting, ESI-MS spectrometry, circular dichroism, and molecular dynamics. The binding affinity results determined by fluorescence spectroscopy are in accordance with those obtained by biosensor-SPR. These small size single G⋅C bp highly specific binders extend the compound database for future biological applications.
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Affiliation(s)
- Abdelbasset A. Farahat
- Department of Chemistry and Center for Diagnostics and Therapeutics Georgia State University, 50 Decatur St SE, Atlanta, GA 30303, USA
- Department of Pharmaceutical Organic Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt
| | - Pu Guo
- Department of Chemistry and Center for Diagnostics and Therapeutics Georgia State University, 50 Decatur St SE, Atlanta, GA 30303, USA
| | - Hadir Shoeib
- Department of Chemistry and Center for Diagnostics and Therapeutics Georgia State University, 50 Decatur St SE, Atlanta, GA 30303, USA
| | - Ananya Paul
- Department of Chemistry and Center for Diagnostics and Therapeutics Georgia State University, 50 Decatur St SE, Atlanta, GA 30303, USA
| | - David W. Boykin
- Department of Chemistry and Center for Diagnostics and Therapeutics Georgia State University, 50 Decatur St SE, Atlanta, GA 30303, USA
| | - W. David Wilson
- Department of Chemistry and Center for Diagnostics and Therapeutics Georgia State University, 50 Decatur St SE, Atlanta, GA 30303, USA
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A. Ismail M, M. El-Sayed W, Shaaban S, A. Abdelwahab G, S. Hamama W. A Review of Cationic Arylfurans and Their Isosteres: Synthesis and Biological Importance. CURR ORG CHEM 2020. [DOI: 10.2174/1385272823666191029114830] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The present study provides an overview of the chemistry and biological importance
of the cationic chalcophene derivatives (furans, thiophenes and selenophenes). The
summarized literature survey includes synthetic methods, reactivity and biological activities
of aryl/hetarylchalcophenes that have been reported mainly from 2001 to 2019 focusing
on monochalcophenes. A discussion demonstrating the proposed mechanisms of some
interesting synthetic routes and linking structure features to biological activities is presented.
These classes of compounds including cationic chalcophenes possess antiproliferative,
antimicrobial and antiprotozoal activities. This review highlights recent advances
for arylchalcophene derivatives and may contribute to the design and structure optimization
of new chalcophene derivatives in the future.
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Affiliation(s)
- Mohamed A. Ismail
- Department of Chemistry, Faculty of Science, Mansoura University, Mansoura 35516, Egypt
| | - Wael M. El-Sayed
- Department of Zoology, Faculty of Science, University of Ain Shams, Abbassia 11566, Cairo, Egypt
| | - Saad Shaaban
- Department of Chemistry, Faculty of Science, Mansoura University, Mansoura 35516, Egypt
| | - Ghada A. Abdelwahab
- Department of Chemistry, Faculty of Science, Mansoura University, Mansoura 35516, Egypt
| | - Wafaa S. Hamama
- Department of Chemistry, Faculty of Science, Mansoura University, Mansoura 35516, Egypt
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5
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A New Generation of Minor-Groove-Binding-Heterocyclic Diamidines That Recognize G·C Base Pairs in an AT Sequence Context. Molecules 2019; 24:molecules24050946. [PMID: 30866557 PMCID: PMC6429135 DOI: 10.3390/molecules24050946] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 02/28/2019] [Accepted: 03/01/2019] [Indexed: 12/17/2022] Open
Abstract
We review the preparation of new compounds with good solution and cell uptake properties that can selectively recognize mixed A·T and G·C bp sequences of DNA. Our underlying aim is to show that these new compounds provide important new biotechnology reagents as well as a new class of therapeutic candidates with better properties and development potential than other currently available agents. In this review, entirely different ways to recognize mixed sequences of DNA by modifying AT selective heterocyclic cations are described. To selectively recognize a G·C base pair an H-bond acceptor must be incorporated with AT recognizing groups as with netropsin. We have used pyridine, azabenzimidazole and thiophene-N-methylbenzimidazole GC recognition units in modules crafted with both rational design and empirical optimization. These modules can selectively and strongly recognize a single G·C base pair in an AT sequence context. In some cases, a relatively simple change in substituents can convert a heterocyclic module from AT to GC recognition selectivity. Synthesis and DNA interaction results for initial example lead modules are described for single G·C base pair recognition compounds. The review concludes with a description of the initial efforts to prepare larger compounds to recognize sequences of DNA with more than one G·C base pairs. The challenges and initial successes are described along with future directions.
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Guo P, Farahat AA, Paul A, Harika NK, Boykin DW, Wilson WD. Compound Shape Effects in Minor Groove Binding Affinity and Specificity for Mixed Sequence DNA. J Am Chem Soc 2018; 140:14761-14769. [PMID: 30353731 PMCID: PMC6399738 DOI: 10.1021/jacs.8b08152] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
AT specific heterocyclic cations that bind in the DNA duplex minor groove have had major successes as cell and nuclear stains and as therapeutic agents which can effectively enter human cells. Expanding the DNA sequence recognition capability of the minor groove compounds could also expand their therapeutic targets and have an impact in many areas, such as modulation of transcription factor biological activity. Success in the design of mixed sequence binding compounds has been achieved with N-methylbenzimidazole ( N-MeBI) thiophenes which are preorganized to fit the shape of the DNA minor groove and H-bond to the -NH of G·C base pairs that project into the minor groove. Initial compounds bind strongly to a single G·C base pair in an AT context with a specificity ratio of 50 ( KD AT-GC/ KD AT) or less and this is somewhat low for biological use. We felt that modifications of compound shape could be used to probe local DNA microstructure in target mixed base pair sequences of DNA and potentially improve the compound binding selectivity. Modifications were made by increasing the size of the benzimidazole N-substituent, for example, by using N-isobutyl instead of N-Me, and by changing the molecular twist by introducing substitutions at specific positions on the aromatic core of the compounds. In both cases, we have been able to achieve a dramatic increase in binding specificity, including no detectible binding to pure AT sequences, without a significant loss in affinity to mixed base pair target sequences.
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Affiliation(s)
- Pu Guo
- Department of Chemistry and Center for Diagnostics and Therapeutics , Georgia State University , 50 Decatur Street South East , Atlanta , Georgia 30303 , United States
| | - Abdelbasset A Farahat
- Department of Chemistry and Center for Diagnostics and Therapeutics , Georgia State University , 50 Decatur Street South East , Atlanta , Georgia 30303 , United States
- Department of Pharmaceutical Organic Chemistry, Faculty of Pharmacy , Mansoura University , Mansoura 35516 , Egypt
| | - Ananya Paul
- Department of Chemistry and Center for Diagnostics and Therapeutics , Georgia State University , 50 Decatur Street South East , Atlanta , Georgia 30303 , United States
| | - Narinder K Harika
- Department of Chemistry and Center for Diagnostics and Therapeutics , Georgia State University , 50 Decatur Street South East , Atlanta , Georgia 30303 , United States
| | - David W Boykin
- Department of Chemistry and Center for Diagnostics and Therapeutics , Georgia State University , 50 Decatur Street South East , Atlanta , Georgia 30303 , United States
| | - W David Wilson
- Department of Chemistry and Center for Diagnostics and Therapeutics , Georgia State University , 50 Decatur Street South East , Atlanta , Georgia 30303 , United States
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7
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An Aromatic Diamidine That Targets Kinetoplast DNA, Impairs the Cell Cycle in Trypanosoma cruzi, and Diminishes Trypomastigote Release from Infected Mammalian Host Cells. Antimicrob Agents Chemother 2016; 60:5867-77. [PMID: 27431229 DOI: 10.1128/aac.01595-15] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 07/12/2016] [Indexed: 11/20/2022] Open
Abstract
Trypanosoma cruzi is the etiological agent of Chagas disease, affecting approximately 10 million people in the Americas and with some 40 million people at risk. The objective of this study was to evaluate the anti-T. cruzi activity of three new diamidines that have a 3,4-ethylenedioxy extension of the thiophene core, designated MB17, MB19, and MB38. All three diamidines exhibited dose-dependent inhibition of epimastigote replication. The mechanisms of action of these diamidines were investigated. Unlike MB17 and MB19, MB38 exhibited a significant increase in the number of annexin-propidium iodide double-labeled cells compared to levels in control parasites. As MB17 had shown a lower 50% inhibitory concentration (IC50) against epimastigote growth, the mechanism of action of this drug was studied in more detail. MB17 triggered a decrease in the intracellular ATP levels. As a consequence, MB17 affected the genomic DNA and kinetoplast DNA (kDNA) and impaired the parasite cell cycle. Moreover, MB17 caused DNA fragmentation, with a more severe effect on kDNA than on nuclear DNA, resulting in dyskinetoplastic cells. MB17 was tested for toxicity and effectiveness for the treatment of infected CHO-K1 cells, exhibiting a 50% cytotoxic concentration (CC50) of 13.47 ± 0.37 μM and an IC50 of 0.14 ± 0.12 μM against trypomastigote release. MB17 also diminished the infection index by 60% at 0.5 μM. In conclusion, despite belonging to the same family, these diamidines have different efficiencies. To summarize, MB17 was the most potent of these diamidines against epimastigotes, producing DNA damage preferentially in kDNA, impairing the parasite cell cycle, and decreasing the infection index and trypomastigote release from infected mammalian host cells, with a high selectivity index (SI) (<90). These data suggest that MB17 could be an interesting lead compound against T. cruzi.
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8
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Berger ML, Maciejewska D, Vanden Eynde JJ, Mottamal M, Żabiński J, Kaźmierczak P, Rezler M, Jarak I, Piantanida I, Karminski-Zamola G, Mayence A, Rebernik P, Kumar A, Ismail MA, Boykin DW, Huang TL. Pentamidine analogs as inhibitors of [(3)H]MK-801 and [(3)H]ifenprodil binding to rat brain NMDA receptors. Bioorg Med Chem 2015; 23:4489-4500. [PMID: 26117647 DOI: 10.1016/j.bmc.2015.06.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 06/05/2015] [Accepted: 06/05/2015] [Indexed: 12/29/2022]
Abstract
The anti-protozoal drug pentamidine is active against opportunistic Pneumocystis pneumonia, but in addition has several other biological targets, including the NMDA receptor (NR). Here we describe the inhibitory potencies of 76 pentamidine analogs at 2 binding sites of the NR, the channel binding site labeled with [(3)H]MK-801 and the [(3)H]ifenprodil binding site. Most analogs acted weaker at the ifenprodil than at the channel site. The spermine-sensitivity of NR inhibition by the majority of the compounds was reminiscent of other long-chain dicationic NR blockers. The potency of the parent compound as NR blocker was increased by modifying the heteroatoms in the bridge connecting the 2 benzamidine moieties and also by integrating the bridge into a seven-membered ring. Docking of the 45 most spermine-sensitive bisbenzamidines to a recently described acidic interface between the N-terminal domains of GluN1 and GluN2B mediating polyamine stimulation of the NR revealed the domain contributed by GluN1 as the most relevant target.
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Affiliation(s)
- Michael L Berger
- Center for Brain Research, Medical University of Vienna, Vienna, Austria.
| | - Dorota Maciejewska
- Department of Organic Chemistry, Medical University of Warsaw, Warsaw, Poland
| | | | | | - Jerzy Żabiński
- Department of Organic Chemistry, Medical University of Warsaw, Warsaw, Poland
| | - Paweł Kaźmierczak
- Department of Organic Chemistry, Medical University of Warsaw, Warsaw, Poland
| | - Mateusz Rezler
- Department of Organic Chemistry, Medical University of Warsaw, Warsaw, Poland
| | - Ivana Jarak
- Department of Organic Chemistry, University of Zagreb, Zagreb, Croatia
| | - Ivo Piantanida
- Department of Organic Chemistry, University of Zagreb, Zagreb, Croatia
| | | | - Annie Mayence
- College of Pharmacy, Xavier University of Louisiana, New Orleans, USA
| | - Patrick Rebernik
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Arvind Kumar
- Department of Chemistry, Georgia State University, Atlanta, GA, USA
| | - Mohamed A Ismail
- Department of Chemistry, Georgia State University, Atlanta, GA, USA
| | - David W Boykin
- Department of Chemistry, Georgia State University, Atlanta, GA, USA
| | - Tien L Huang
- College of Pharmacy, Xavier University of Louisiana, New Orleans, USA
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9
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Paul A, Nanjunda R, Kumar A, Laughlin S, Nhili R, Depauw S, Deuser SS, Chai Y, Chaudhary AS, David-Cordonnier MH, Boykin DW, Wilson WD. Mixed up minor groove binders: Convincing A·T specific compounds to recognize a G·C base pair. Bioorg Med Chem Lett 2015; 25:4927-4932. [PMID: 26051649 DOI: 10.1016/j.bmcl.2015.05.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 05/06/2015] [Indexed: 01/08/2023]
Abstract
DNA minor-groove-binding compounds have limited biological applications, in part due to problems with sequence specificity that cause off-target effects. A model to enhance specificity has been developed with the goal of preparing compounds that bind to two AT sites separated by G·C base pairs. Compounds of interest were probed using thermal melting, circular dichroism, mass spectrometry, biosensor-SPR, and molecular modeling methods. A new minor groove binder that can strongly and specifically recognize a single G·C base pair with flanking AT sequences has been prepared. This multi-site DNA recognition mode offers novel design principles to recognize entirely new DNA motifs.
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Affiliation(s)
- Ananya Paul
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30303, USA
| | - Rupesh Nanjunda
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30303, USA
| | - Arvind Kumar
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30303, USA
| | - Sarah Laughlin
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30303, USA
| | - Raja Nhili
- UMR-S1172-Jean-Pierre Aubert Research Centre (JPARC), INSERM-University of Lille and Centre Hospitalier of Lille, Institut pour la Recherche sur le Cancer de Lille, Place de Verdun, F-59045 Lille Cedex, France
| | - Sabine Depauw
- UMR-S1172-Jean-Pierre Aubert Research Centre (JPARC), INSERM-University of Lille and Centre Hospitalier of Lille, Institut pour la Recherche sur le Cancer de Lille, Place de Verdun, F-59045 Lille Cedex, France
| | - Shelby Sheldon Deuser
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30303, USA
| | - Yun Chai
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30303, USA
| | - Arpana S Chaudhary
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30303, USA
| | - Marie-Hélène David-Cordonnier
- UMR-S1172-Jean-Pierre Aubert Research Centre (JPARC), INSERM-University of Lille and Centre Hospitalier of Lille, Institut pour la Recherche sur le Cancer de Lille, Place de Verdun, F-59045 Lille Cedex, France
| | - David W Boykin
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30303, USA
| | - W David Wilson
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30303, USA.
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10
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Paul A, Chai Y, Boykin DW, Wilson WD. Understanding mixed sequence DNA recognition by novel designed compounds: the kinetic and thermodynamic behavior of azabenzimidazole diamidines. Biochemistry 2014; 54:577-87. [PMID: 25495885 PMCID: PMC4303320 DOI: 10.1021/bi500989r] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Sequence-specific recognition of DNA by small organic molecules offers a potentially effective approach for the external regulation of gene expression and is an important goal in cell biochemistry. Rational design of compounds from established modules can potentially yield compounds that bind strongly and selectively with specific DNA sequences. An initial approach is to start with common A·T bp recognition molecules and build in G·C recognition units. Here we report on the DNA interaction of a synthetic compound that specifically binds to a G·C bp in the minor groove of DNA by using an azabenzimidazole moiety. The detailed interactions were evaluated with biosensor-surface plasmon resonance (SPR), isothermal calorimetric (ITC), and mass spectrometry (ESI-MS) methods. The compound, DB2277, binds with single G·C bp containing sequences with sub-nanomolar potency and displays slow dissociation kinetics and high selectivity. A detailed thermodynamic and kinetic study at different experimental salt concentrations and temperatures shows that the binding free energy is salt concentration dependent but essentially temperature independent under our experimental conditions, and binding enthalpy is temperature dependent but salt concentration independent. The results show that in the proper compound structural context novel heterocyclic cations can be designed to strongly recognize complex DNA sequences.
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Affiliation(s)
- Ananya Paul
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University , Atlanta, Georgia 30303-3083, United States
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