501
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502
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Bonne D, Constantieux T, Coquerel Y, Rodriguez J. Asymmetric organocascades involving the formation of two C–heteroatom bonds from two distinct heteroatoms. Org Biomol Chem 2012; 10:3969-73. [DOI: 10.1039/c2ob25248a] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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503
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Harding SL, Savage GP. Facial selectivity induced by N-aryl atropisomerism in benzonitrile oxide cycloadditions with 4-methylene-2-oxazolidinones. Org Biomol Chem 2012; 10:4759-66. [DOI: 10.1039/c2ob25271f] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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504
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First report of anti-Trichomonas vaginalis activity of the medicinal plant Polygala decumbens from the Brazilian semi-arid region, Caatinga. Parasitol Res 2011; 110:2581-7. [DOI: 10.1007/s00436-011-2787-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Accepted: 12/13/2011] [Indexed: 10/14/2022]
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505
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Regio- and enantio-selective glycosylation of tetrahydroprotoberberines by Gliocladium deliquescens NRRL1086 resulting in unique alkaloidal glycosides. Appl Microbiol Biotechnol 2011; 93:2357-64. [DOI: 10.1007/s00253-011-3795-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Revised: 11/24/2011] [Accepted: 11/25/2011] [Indexed: 10/14/2022]
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506
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Jiao WH, Huang XJ, Yang JS, Yang F, Piao SJ, Gao H, Li J, Ye WC, Yao XS, Chen WS, Lin HW. Dysidavarones A–D, New Sesquiterpene Quinones from the Marine Sponge Dysidea avara. Org Lett 2011; 14:202-5. [PMID: 22133022 DOI: 10.1021/ol202994c] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Wei-Hua Jiao
- Laboratory of Marine Drugs, Department of Pharmacy, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P. R. China, Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632, P. R. China, and National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, P. R. China
| | - Xiao-Jun Huang
- Laboratory of Marine Drugs, Department of Pharmacy, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P. R. China, Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632, P. R. China, and National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, P. R. China
| | - Ji-Si Yang
- Laboratory of Marine Drugs, Department of Pharmacy, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P. R. China, Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632, P. R. China, and National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, P. R. China
| | - Fan Yang
- Laboratory of Marine Drugs, Department of Pharmacy, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P. R. China, Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632, P. R. China, and National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, P. R. China
| | - Shu-Jian Piao
- Laboratory of Marine Drugs, Department of Pharmacy, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P. R. China, Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632, P. R. China, and National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, P. R. China
| | - Hao Gao
- Laboratory of Marine Drugs, Department of Pharmacy, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P. R. China, Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632, P. R. China, and National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, P. R. China
| | - Jia Li
- Laboratory of Marine Drugs, Department of Pharmacy, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P. R. China, Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632, P. R. China, and National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, P. R. China
| | - Wen-Cai Ye
- Laboratory of Marine Drugs, Department of Pharmacy, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P. R. China, Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632, P. R. China, and National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, P. R. China
| | - Xin-Sheng Yao
- Laboratory of Marine Drugs, Department of Pharmacy, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P. R. China, Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632, P. R. China, and National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, P. R. China
| | - Wan-Sheng Chen
- Laboratory of Marine Drugs, Department of Pharmacy, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P. R. China, Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632, P. R. China, and National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, P. R. China
| | - Hou-Wen Lin
- Laboratory of Marine Drugs, Department of Pharmacy, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P. R. China, Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632, P. R. China, and National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, P. R. China
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507
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Wang B, Deng J, Gao Y, Zhu L, He R, Xu Y. The screening toolbox of bioactive substances from natural products: A review. Fitoterapia 2011; 82:1141-51. [DOI: 10.1016/j.fitote.2011.08.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2011] [Revised: 07/30/2011] [Accepted: 07/30/2011] [Indexed: 10/17/2022]
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508
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Hoveyda HR, Marsault E, Gagnon R, Mathieu AP, Vézina M, Landry A, Wang Z, Benakli K, Beaubien S, Saint-Louis C, Brassard M, Pinault JF, Ouellet L, Bhat S, Ramaseshan M, Peng X, Foucher L, Beauchemin S, Bhérer P, Veber DF, Peterson ML, Fraser GL. Optimization of the Potency and Pharmacokinetic Properties of a Macrocyclic Ghrelin Receptor Agonist (Part I): Development of Ulimorelin (TZP-101) from Hit to Clinic. J Med Chem 2011; 54:8305-20. [DOI: 10.1021/jm2007062] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Hamid R. Hoveyda
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Eric Marsault
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - René Gagnon
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Axel P. Mathieu
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Martin Vézina
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Annick Landry
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Zhigang Wang
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Kamel Benakli
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Sylvie Beaubien
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Carl Saint-Louis
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Martin Brassard
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | | | - Luc Ouellet
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Shridhar Bhat
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Mahesh Ramaseshan
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Xiaowen Peng
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Laurence Foucher
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Sophie Beauchemin
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Patrick Bhérer
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Daniel F. Veber
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Mark L. Peterson
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Graeme L. Fraser
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
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509
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Kong DX, Guo MY, Xiao ZH, Chen LL, Zhang HY. Historical Variation of Structural Novelty in a Natural Product Library. Chem Biodivers 2011; 8:1968-77. [DOI: 10.1002/cbdv.201100156] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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510
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Salvador JAR, Moreira VM, Pinto RMA, Leal AS, Le Roux C. Bismuth(III) Triflate-Based Catalytic Direct Opening of Oleanolic Hydroxy-γ-lactones to Afford 12-Oxo-28-carboxylic Acids. Adv Synth Catal 2011. [DOI: 10.1002/adsc.201100155] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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511
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Chlipala GE, Mo S, Orjala J. Chemodiversity in freshwater and terrestrial cyanobacteria - a source for drug discovery. Curr Drug Targets 2011; 12:1654-73. [PMID: 21561419 PMCID: PMC3244969 DOI: 10.2174/138945011798109455] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Accepted: 03/02/2011] [Indexed: 12/16/2022]
Abstract
Cyanobacteria are considered a promising source for new pharmaceutical lead compounds and a large number of chemically diverse and bioactive metabolites have been obtained from cyanobacteria over the last few decades. This review highlights the structural diversity of natural products from freshwater and terrestrial cyanobacteria. The review is divided into three areas: cytotoxic metabolites, protease inhibitors, and antimicrobial metabolites. The first section discusses the potent cytotoxins cryptophycin and tolytoxin. The second section covers protease inhibitors from freshwater and terrestrial cyanobacteria and is divided in five subsections according to structural class: aeruginosins, cyanopeptolins, microviridins, anabaenopeptins, and microginins. Structure activity relationships are discussed within each protease inhibitor class. The third section, antimicrobial metabolites from freshwater and terrestrial cyanobacteria, is divided by chemical class in three subsections: alkaloids, peptides and terpenoids. These examples emphasize the structural diversity and drug development potential of natural products from freshwater and terrestrial cyanobacteria.
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Affiliation(s)
- George E. Chlipala
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 S. Wood St., Chicago, Illinois, 60612
| | - Shunyan Mo
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 S. Wood St., Chicago, Illinois, 60612
| | - Jimmy Orjala
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 S. Wood St., Chicago, Illinois, 60612
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512
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Coprismycins A and B, neuroprotective phenylpyridines from the dung beetle-associated bacterium, Streptomyces sp. Bioorg Med Chem Lett 2011; 21:5715-8. [DOI: 10.1016/j.bmcl.2011.08.023] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 07/25/2011] [Accepted: 08/03/2011] [Indexed: 11/22/2022]
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513
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Abstract
Rapid advances in our collective understanding of biomolecular structure and, in concert, of biochemical systems, coupled with developments in computational methods, have massively impacted the field of medicinal chemistry over the past two decades, with even greater changes appearing on the horizon. In this perspective, we endeavor to profile some of the most prominent determinants of change and speculate as to further evolution that may consequently occur during the next decade. The five main angles to be addressed are: protein-protein interactions; peptides and peptidomimetics; molecular diversity and pharmacological space; molecular pharmacodynamics (significance, potential and challenges); and early-stage clinical efficacy and safety. We then consider, in light of these, the future of medicinal chemistry and the educational preparation that will be required for future medicinal chemists.
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Affiliation(s)
- Seetharama D Satyanarayanajois
- Basic Pharmaceutical Sciences, College of Pharmacy, University of Louisiana at Monroe, 1800 Bienville Drive, Monroe LA 71201, USA.
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514
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King GF. Venoms as a platform for human drugs: translating toxins into therapeutics. Expert Opin Biol Ther 2011; 11:1469-84. [PMID: 21939428 DOI: 10.1517/14712598.2011.621940] [Citation(s) in RCA: 375] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
INTRODUCTION An extraordinarily diverse range of animals have evolved venoms for predation, defence, or competitor deterrence. The major components of most venoms are peptides and proteins that are often protease-resistant due to their disulfide-rich architectures. Some of these toxins have become valuable as pharmacological tools and/or therapeutics due to their extremely high specificity and potency for particular molecular targets. There are currently six FDA-approved drugs derived from venom peptides or proteins. AREAS COVERED This article surveys the current pipeline of venom-derived therapeutics and critically examines the potential of peptide and protein drugs derived from venoms. Emerging trends are identified, including an increasing industry focus on disulfide-rich venom peptides and the use of a broader array of molecular targets in order to develop venom-based therapeutics for treating a wider range of clinical conditions. EXPERT OPINION Key technical advances in combination with a renewed industry-wide focus on biologics have converged to provide a larger than ever pipeline of venom-derived therapeutics. Disulfide-rich venom peptides obviate some of the traditional disadvantages of therapeutic peptides and some may be suitable for oral administration. Moreover, some venom peptides can breach the blood brain barrier and translocate across cell membranes, which opens up the possibility of exploiting molecular targets not previously accessible to peptide drugs.
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Affiliation(s)
- Glenn F King
- The University of Queensland, Institute for Molecular Bioscience, 306 Carmody Road, St Lucia, Queensland 4072, Australia.
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515
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Ait-Mohamed O, Battisti V, Joliot V, Fritsch L, Pontis J, Medjkane S, Redeuilh C, Lamouri A, Fahy C, Rholam M, Atmani D, Ait-Si-Ali S. Acetonic extract of Buxus sempervirens induces cell cycle arrest, apoptosis and autophagy in breast cancer cells. PLoS One 2011; 6:e24537. [PMID: 21935420 PMCID: PMC3174189 DOI: 10.1371/journal.pone.0024537] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Accepted: 08/12/2011] [Indexed: 12/19/2022] Open
Abstract
Plants are an invaluable source of potential new anti-cancer drugs. Here, we investigated the cytotoxic activity of the acetonic extract of Buxus sempervirens on five breast cancer cell lines, MCF7, MCF10CA1a and T47D, three aggressive triple positive breast cancer cell lines, and BT-20 and MDA-MB-435, which are triple negative breast cancer cell lines. As a control, MCF10A, a spontaneously immortalized but non-tumoral cell line has been used. The acetonic extract of Buxus sempervirens showed cytotoxic activity towards all the five studied breast cancer cell lines with an IC(50) ranging from 7.74 µg/ml to 12.5 µg/ml. Most importantly, the plant extract was less toxic towards MCF10A with an IC(50) of 19.24 µg/ml. Fluorescence-activated cell sorting (FACS) analysis showed that the plant extract induced cell death and cell cycle arrest in G0/G1 phase in MCF7, T47D, MCF10CA1a and BT-20 cell lines, concomitant to cyclin D1 downregulation. Application of MCF7 and MCF10CA1a respective IC(50) did not show such effects on the control cell line MCF10A. Propidium iodide/Annexin V double staining revealed a pre-apoptotic cell population with extract-treated MCF10CA1a, T47D and BT-20 cells. Transmission electron microscopy analyses indicated the occurrence of autophagy in MCF7 and MCF10CA1a cell lines. Immunofluorescence and Western blot assays confirmed the processing of microtubule-associated protein LC3 in the treated cancer cells. Moreover, we have demonstrated the upregulation of Beclin-1 in these cell lines and downregulation of Survivin and p21. Also, Caspase-3 detection in treated BT-20 and T47D confirmed the occurrence of apoptosis in these cells. Our findings indicate that Buxus sempervirens extract exhibit promising anti-cancer activity by triggering both autophagic cell death and apoptosis, suggesting that this plant may contain potential anti-cancer agents for single or combinatory cancer therapy against breast cancer.
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Affiliation(s)
- Ouardia Ait-Mohamed
- Laboratoire de Biochimie Appliquée, Faculté des Sciences de la Nature et de la vie, Université de Béjaia, Béjaia, Algeria
| | - Valentine Battisti
- Laboratoire Epigénétique et Destin Cellulaire, UMR7216, Centre National de la Recherche Scientifique (CNRS), Université Paris Diderot Sorbonne Paris Cité, Paris, France
| | - Véronique Joliot
- Laboratoire Epigénétique et Destin Cellulaire, UMR7216, Centre National de la Recherche Scientifique (CNRS), Université Paris Diderot Sorbonne Paris Cité, Paris, France
| | - Lauriane Fritsch
- Laboratoire Epigénétique et Destin Cellulaire, UMR7216, Centre National de la Recherche Scientifique (CNRS), Université Paris Diderot Sorbonne Paris Cité, Paris, France
| | - Julien Pontis
- Laboratoire Epigénétique et Destin Cellulaire, UMR7216, Centre National de la Recherche Scientifique (CNRS), Université Paris Diderot Sorbonne Paris Cité, Paris, France
| | - Souhila Medjkane
- Laboratoire Epigénétique et Destin Cellulaire, UMR7216, Centre National de la Recherche Scientifique (CNRS), Université Paris Diderot Sorbonne Paris Cité, Paris, France
| | - Catherine Redeuilh
- Laboratoire ITODYS, UMR7086 CNRS, Université Paris Diderot Sorbonne Paris Cité, Paris, France
| | - Aazdine Lamouri
- Laboratoire ITODYS, UMR7086 CNRS, Université Paris Diderot Sorbonne Paris Cité, Paris, France
| | - Christine Fahy
- Laboratoire ITODYS, UMR7086 CNRS, Université Paris Diderot Sorbonne Paris Cité, Paris, France
| | - Mohamed Rholam
- Laboratoire ITODYS, UMR7086 CNRS, Université Paris Diderot Sorbonne Paris Cité, Paris, France
| | - Djebbar Atmani
- Laboratoire de Biochimie Appliquée, Faculté des Sciences de la Nature et de la vie, Université de Béjaia, Béjaia, Algeria
| | - Slimane Ait-Si-Ali
- Laboratoire Epigénétique et Destin Cellulaire, UMR7216, Centre National de la Recherche Scientifique (CNRS), Université Paris Diderot Sorbonne Paris Cité, Paris, France
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516
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Crawford JM, Portmann C, Kontnik R, Walsh CT, Clardy J. NRPS substrate promiscuity diversifies the xenematides. Org Lett 2011; 13:5144-7. [PMID: 21888371 PMCID: PMC3184645 DOI: 10.1021/ol2020237] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
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Xenematide, a cyclic depsipeptide antibiotic produced by Xenorhabdus nematophila, had a candidate nonribosomal peptide synthetase (NRPS) with atypical features. Differential metabolite analysis between a mutant and wildtype validated that this stand-alone NRPS was required for xenematide production, and further analysis led to a series of new xenematide derivatives encoded by the same NRPS. Our results indicate that adenylation domain promiscuity and relaxed downstream processing in the X. nematophila NRPS provide a conduit for xenematide diversification.
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Affiliation(s)
- Jason M Crawford
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, Massachusetts 02115, USA
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517
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Thornburg CC, Thimmaiah M, Shaala LA, Hau AM, Malmo JM, Ishmael JE, Youssef DT, McPhail KL. Cyclic depsipeptides, grassypeptolides D and E and Ibu-epidemethoxylyngbyastatin 3, from a Red Sea Leptolyngbya cyanobacterium. JOURNAL OF NATURAL PRODUCTS 2011; 74:1677-85. [PMID: 21806012 PMCID: PMC3170410 DOI: 10.1021/np200270d] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Two new grassypeptolides and a lyngbyastatin analogue, together with the known dolastatin 12, have been isolated from field collections and laboratory cultures of the marine cyanobacterium Leptolyngbya sp. collected from the SS Thistlegorm shipwreck in the Red Sea. The overall stereostructures of grassypeptolides D (1) and E (2) and Ibu-epidemethoxylyngbyastatin 3 (3) were determined by a combination of 1D and 2D NMR experiments, MS analysis, Marfey's methodology, and HPLC-MS. Compounds 1 and 2 contain 2-methyl-3-aminobutyric acid and 2-aminobutyric acid, while biosynthetically distinct 3 contains 3-amino-2-methylhexanoic acid and the β-keto amino acid 4-amino-2,2-dimethyl-3-oxopentanoic acid (Ibu). Grassypeptolides D (1) and E (2) showed significant cytotoxicity to HeLa (IC₅₀ = 335 and 192 nM, respectively) and mouse neuro-2a blastoma cells (IC₅₀ = 599 and 407 nM, respectively), in contrast to Ibu-epidemethoxylyngbyastatin 3 (neuro-2a cells, IC₅₀ > 10 μM) and dolastatin 12 (neuro-2a cells, IC₅₀ > 1 μM).
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Affiliation(s)
| | | | | | | | | | | | | | - Kerry L. McPhail
- To whom correspondence should be addressed. Tel: 541 737 5808. Fax: 541 737 3999.
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518
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Studies on the synthesis and the antimicrobial and antioxidant activities of a novel class of fluorescein-based glycosides. Carbohydr Res 2011; 346:2362-7. [PMID: 21903205 DOI: 10.1016/j.carres.2011.08.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Revised: 07/27/2011] [Accepted: 08/03/2011] [Indexed: 11/22/2022]
Abstract
Facile glycosylation of a fluorescein diol derivative with per-O-acetyl/benzoyl sugar derivatives using BF(3)·Et(2)O catalyst resulted in the formation of the expected glycosides in 54-66% yield. The biological screening of the glycosides against different microbes shows good inhibitory activity. The antioxidant activity of the fluorescein-based glycosides shows remarkable inhibition (IC(50) ∼80%).
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519
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Fu H, Fu W, Sun M, Shou Q, Zhai Y, Cheng H, Teng L, Mou X, Li Y, Wan S, Zhang S, Xu Q, Zhang X, Wang J, Zhu J, Wang X, Xu X, Lv G, Jin L, Guo W, Ke Y. Kinetic Cellular Phenotypic Profiling: Prediction, Identification, and Analysis of Bioactive Natural Products. Anal Chem 2011; 83:6518-26. [DOI: 10.1021/ac201670e] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Huiying Fu
- Program in Molecular Cell Biology, Department of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Wenqing Fu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Mingjiao Sun
- Program in Molecular Cell Biology, Department of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Qiyang Shou
- Zhejiang University of Traditional Chinese Medicine, Hangzhou 310053, China
| | - Yunyan Zhai
- Program in Molecular Cell Biology, Department of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Hongqiang Cheng
- Program in Molecular Cell Biology, Department of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Li Teng
- Program in Molecular Cell Biology, Department of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Xiaozhou Mou
- Program in Molecular Cell Biology, Department of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Yanwei Li
- Program in Molecular Cell Biology, Department of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Shuying Wan
- Program in Molecular Cell Biology, Department of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Shanshan Zhang
- Program in Molecular Cell Biology, Department of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Qinqin Xu
- Program in Molecular Cell Biology, Department of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Xue Zhang
- Program in Molecular Cell Biology, Department of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Jiucun Wang
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Jenny Zhu
- ACEA Biosciences Incorporated, San Diego, California 92126, United States
| | - Xiaobo Wang
- ACEA Biosciences Incorporated, San Diego, California 92126, United States
| | - Xiao Xu
- ACEA Biosciences Incorporated, San Diego, California 92126, United States
| | - Guiyuan Lv
- Zhejiang University of Traditional Chinese Medicine, Hangzhou 310053, China
| | - Li Jin
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Wensheng Guo
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200433, China
- Center for Clinical Epidemiology and Biostatistics, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Yuehai Ke
- Program in Molecular Cell Biology, Department of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou 310058, China
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520
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Abstract
The study of bacterial symbionts of eukaryotic hosts has become a powerful discovery engine for chemistry. This highlight looks at four case studies that exemplify the range of chemistry and biology involved in these symbioses: a bacterial symbiont of a fungus and a marine invertebrate that produce compounds with significant anticancer activity, and bacterial symbionts of insects and nematodes that produce compounds that regulate multilateral symbioses.
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Affiliation(s)
- Jason M Crawford
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA
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521
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Where have All the Antibiotics Gone? CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY 2011; 17:287-90. [PMID: 18382641 DOI: 10.1155/2006/707296] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The discovery of antibiotics some 60 years ago was anticipated to herald the end of infectious diseases. However, microbial evolution and genetic jugglery have dispelled this notion; the constant increase in the appearance of resistant strains has not been matched by the introduction of new therapeutic agents. On the contrary, the dire need for novel antibiotics has coincided with a reduction in antibiotic discovery programs in the pharmaceutical industry. As a result, the treatment of microbial diseases has reached a point where many infections are essentially untreatable by the antimicrobial agents currently available. At the present time, numerous initiatives are being undertaken by physicians and by governments in an attempt to redress this situation. In addition, alternative approaches to antibiotics for the treatment of infectious diseases are being explored intensively.
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522
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Xu D, Saeed A, Wang Y, Seidel V, Sandström G, Yu J. Natural products modulate Shigella-host-cell interaction. J Med Microbiol 2011; 60:1626-1632. [PMID: 21719574 DOI: 10.1099/jmm.0.030254-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
This study focused on identifying possible new options derived from natural sources for the treatment of bacterial infections. Several natural products were investigated for their potential in modulating Shigella-host-cell interactions. The proliferation of Shigella sonnei was effectively inhibited inside HEp-2 cells in the presence of 4-methoxycinnamic acid and propolin D. Propolin D also significantly reduced the apoptosis of infected macrophage-like U937 cells and moderately reduced the secretion of interleukin (IL)-1β and IL-18, which probably resulted from the inhibition of invasion plasmid antigen B secretion by this compound. Further characterization showed that propolin D did not prevent escape of Shigella from phagocytic vacuoles, as evidenced by actin-based motility and by the fact that addition of chloroquine did not further reduce the number of intracellular c.f.u. The role of propolin D in modulating autophagy could not be established under the experimental conditions used. As these compounds had no direct anti-Shigella activity in vitro, it was concluded that these compounds modulated Shigella-host-cell interactions by targeting yet-to-be defined mechanisms that provide benefits to host cells.
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Affiliation(s)
- Dan Xu
- Centre for Vaccine Development, School of Life Sciences, Xi'an JiaoTong University, Xi'an, PR China
| | - Amir Saeed
- Center for Microbiological Preparedness (KCB), Smittskyddsinstitutet, SE-171 82 Solna, Sweden
| | - Yili Wang
- Centre for Vaccine Development, School of Life Sciences, Xi'an JiaoTong University, Xi'an, PR China
| | - Véronique Seidel
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK
| | - Gunnar Sandström
- Center for Microbiological Preparedness (KCB), Smittskyddsinstitutet, SE-171 82 Solna, Sweden
| | - Jun Yu
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK.,Centre for Vaccine Development, School of Life Sciences, Xi'an JiaoTong University, Xi'an, PR China
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523
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Karioti A, Sokovic M, Ciric A, Koukoulitsa C, Bilia AR, Skaltsa H. Antimicrobial properties of Quercus ilex L. proanthocyanidin dimers and simple phenolics: evaluation of their synergistic activity with conventional antimicrobials and prediction of their pharmacokinetic profile. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:6412-6422. [PMID: 21563833 DOI: 10.1021/jf2011535] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The antibacterial and antifungal activities of an ample number of phenolic compounds isolated from Quercus ilex leaves, belonging to the classes of flavonoids, proanthocyanidins, and phenolic acids, are discussed. The isolation of A type proanthocyanidin, (+)-epigallocatechin-(2β→O→7, 4β→8)-(+)-catechin is reported for the first time. Its structure was established by means of highfield NMR (correlation spectroscopy, heteronuclear single quantum correlation, heteronuclear multiple bond correlation, and rotating frame Overhauser effect spectroscopy) and MS spectral analyses, while its absolute configuration was determined by circular dichroism measurements. The isolated compounds were tested for their antimicrobial effects against eight human bacterial species and 14 fungal species. In a second step, the most potent compounds were tested in combination with the conventional fungicides, bifonazole and ketoconazole, to evaluate possible synergistic effects. Results showed that proanthocyanidins 3 and 4 when combined with bifonazole and ketoconazole increase the activity of both of these conventional fungicides. Moreover, the pharmacokinetic profile of the isolated compounds was investigated using computational methods.
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Affiliation(s)
- Anastasia Karioti
- Department of Pharmacognosy and Chemistry of Natural Products, School of Pharmacy, University of Athens , Panepistimiopolis, Zografou, 15771 Athens, Greece
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524
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Khan SI, Zhao J, Khan IA, Walker LA, Dasmahapatra AK. Potential utility of natural products as regulators of breast cancer-associated aromatase promoters. Reprod Biol Endocrinol 2011; 9:91. [PMID: 21693041 PMCID: PMC3142499 DOI: 10.1186/1477-7827-9-91] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Accepted: 06/21/2011] [Indexed: 12/21/2022] Open
Abstract
Aromatase, the key enzyme in estrogen biosynthesis, converts androstenedione to estrone and testosterone to estradiol. The enzyme is expressed in various tissues such as ovary, placenta, bone, brain, skin, and adipose tissue. Aromatase enzyme is encoded by a single gene CYP 19A1 and its expression is controlled by tissue-specific promoters. Aromatase mRNA is primarily transcribed from promoter I.4 in normal breast tissue and physiological levels of aromatase are found in breast adipose stromal fibroblasts. Under the conditions of breast cancer, as a result of the activation of a distinct set of aromatase promoters (I.3, II, and I.7) aromatase expression is enhanced leading to local overproduction of estrogen that promotes breast cancer. Aromatase is considered as a potential target for endocrine treatment of breast cancer but due to nonspecific reduction of aromatase activity in other tissues, aromatase inhibitors (AIs) are associated with undesirable side effects such as bone loss, and abnormal lipid metabolism. Inhibition of aromatase expression by inactivating breast tumor-specific aromatase promoters can selectively block estrogen production at the tumor site. Although several synthetic chemical compounds and nuclear receptor ligands are known to inhibit the activity of the tumor-specific aromatase promoters, further development of more specific and efficacious drugs without adverse effects is still warranted. Plants are rich in chemopreventive agents that have a great potential to be used in chemotherapy for hormone dependent breast cancer which could serve as a source for natural AIs. In this brief review, we summarize the studies on phytochemicals such as biochanin A, genistein, quercetin, isoliquiritigenin, resveratrol, and grape seed extracts related to their effect on the activation of breast cancer-associated aromatase promoters and discuss their aromatase inhibitory potential to be used as safer chemotherapeutic agents for specific hormone-dependent breast cancer.
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Affiliation(s)
- Shabana I Khan
- National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, University, MS 38677, USA
- Department of Pharmacognosy, University of Mississippi, University, MS 38677, USA
| | - Jianping Zhao
- National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, University, MS 38677, USA
| | - Ikhlas A Khan
- National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, University, MS 38677, USA
- Department of Pharmacognosy, University of Mississippi, University, MS 38677, USA
| | - Larry A Walker
- National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, University, MS 38677, USA
- Department of Pharmacology, University of Mississippi, MS 38677, USA
- University of Mississippi Cancer Institute, University of Mississippi, University, MS 38677, USA
| | - Asok K Dasmahapatra
- National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, University, MS 38677, USA
- Department of Pharmacology, University of Mississippi, MS 38677, USA
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525
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Abstract
We report a bacterial system for the evolution of cyclic peptides that makes use of an expanded set of amino acid building blocks. Orthogonal aminoacyl-tRNA synthetase/tRNA(CUA) pairs, together with a split intein system were used to biosynthesize a library of ribosomal peptides containing amino acids with unique structures and reactivities. This peptide library was subsequently used to evolve an inhibitor of HIV protease using a selection based on cellular viability. Two of three cyclic peptides isolated after two rounds of selection contained the keto amino acid p-benzoylphenylalanine (pBzF). The most potent peptide (G12: GIXVSL; X=pBzF) inhibited HIV protease through the formation of a covalent Schiff base adduct of the pBzF residue with the ε-amino group of Lys 14 on the protease. This result suggests that an expanded genetic code can confer an evolutionary advantage in response to selective pressure. Moreover, the combination of natural evolutionary processes with chemically biased building blocks provides another strategy for the generation of biologically active peptides using microbial systems.
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526
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527
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Zhang H, Jin H, Ji LZ, Tao K, Liu W, Zhao HY, Hou TP. Design, synthesis, and bioactivities screening of a diaryl ketone-inspired pesticide molecular library as derived from natural products. Chem Biol Drug Des 2011; 78:94-100. [PMID: 21457470 DOI: 10.1111/j.1747-0285.2011.01082.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Three natural products, 1,5-diphenylpentan-1-one, 1,5-diphenylpent-2-en-1-one, and 3-hydroxy-1,5-diphenylpentan-1-one, with good insecticidal activities were extracted from Stellera chamaejasme L. Based on their shared diaryl ketone moiety as 'pharmacophores', a series of diaryl ketones were synthesized and tested for insecticidal activity, acetylcholinesterase inhibitory activity, and antifungal activity. All synthesized compounds showed poor insecticidal and acetylcholinesterase inhibitory activities. Compound III with a furyl ring showed strong activities against plant pathogenic fungi. The IC(50) of compound (E)-1-(2,4-dichlorophenyl)-3-(furan-2-yl)- -prop-2-en-1-one (III(2) ) was 1.20 mg/L against Rhizoctonia solani, suggesting its strong potential as a novel antifungal drug.
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Affiliation(s)
- Hong Zhang
- Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
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528
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Jeon JG, Rosalen PL, Falsetta ML, Koo H. Natural products in caries research: current (limited) knowledge, challenges and future perspective. Caries Res 2011; 45:243-63. [PMID: 21576957 PMCID: PMC3104868 DOI: 10.1159/000327250] [Citation(s) in RCA: 186] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2010] [Accepted: 03/08/2011] [Indexed: 02/04/2023] Open
Abstract
Dental caries is the most prevalent and costly oral infectious disease worldwide. Virulent biofilms firmly attached to tooth surfaces are prime biological factors associated with this disease. The formation of an exopolysaccharide-rich biofilm matrix, acidification of the milieu and persistent low pH at the tooth-biofilm interface are major controlling virulence factors that modulate dental caries pathogenesis. Each one offers a selective therapeutic target for prevention. Although fluoride, delivered in various modalities, remains the mainstay for the prevention of caries, additional approaches are required to enhance its effectiveness. Available antiplaque approaches are based on the use of broad-spectrum microbicidal agents, e.g. chlorhexidine. Natural products offer a rich source of structurally diverse substances with a wide range of biological activities, which could be useful for the development of alternative or adjunctive anticaries therapies. However, it is a challenging approach owing to complex chemistry and isolation procedures to derive active compounds from natural products. Furthermore, most of the studies have been focused on the general inhibitory effects on glucan synthesis as well as on bacterial metabolism and growth, often employing methods that do not address the pathophysiological aspects of the disease (e.g. bacteria in biofilms) and the length of exposure/retention in the mouth. Thus, the true value of natural products in caries prevention and/or their exact mechanisms of action remain largely unknown. Nevertheless, natural substances potentially active against virulent properties of cariogenic organisms have been identified. This review focuses on gaps in the current knowledge and presents a model for investigating the use of natural products in anticaries chemotherapy.
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Affiliation(s)
- J-G Jeon
- Department of Preventive Dentistry, BK 21 Program, School of Dentistry and Institute of Oral Bioscience, Chonbuk National University, Jeonju, Republic of Korea
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529
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530
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Isidro-Llobet A, Murillo T, Bello P, Cilibrizzi A, Hodgkinson JT, Galloway WRJD, Bender A, Welch M, Spring DR. Diversity-oriented synthesis of macrocyclic peptidomimetics. Proc Natl Acad Sci U S A 2011; 108:6793-8. [PMID: 21383137 PMCID: PMC3084124 DOI: 10.1073/pnas.1015267108] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Structurally diverse libraries of novel small molecules represent important sources of biologically active agents. In this paper we report the development of a diversity-oriented synthesis strategy for the generation of diverse small molecules based around a common macrocyclic peptidomimetic framework, containing structural motifs present in many naturally occurring bioactive compounds. Macrocyclic peptidomimetics are largely underrepresented in current small-molecule screening collections owing primarily to synthetic intractability; thus novel molecules based around these structures represent targets of significant interest, both from a biological and a synthetic perspective. In a proof-of-concept study, the synthesis of a library of 14 such compounds was achieved. Analysis of chemical space coverage confirmed that the compound structures indeed occupy underrepresented areas of chemistry in screening collections. Crucial to the success of this approach was the development of novel methodologies for the macrocyclic ring closure of chiral α-azido acids and for the synthesis of diketopiperazines using solid-supported N methylmorpholine. Owing to their robust and flexible natures, it is envisaged that both new methodologies will prove to be valuable in a wider synthetic context.
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Affiliation(s)
- Albert Isidro-Llobet
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
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531
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532
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533
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Ramallo IA, Salazar MO, Mendez L, Furlan RLE. Chemically engineered extracts: source of bioactive compounds. Acc Chem Res 2011; 44:241-50. [PMID: 21355557 DOI: 10.1021/ar100106n] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Biological research and drug discovery critically depend on access to libraries of small molecules that have an affinity for biomacromolecules. By virtue of their sustained success as sources of lead compounds, natural products are recognized as "privileged" starting points in structural space for library development. Compared with synthetic compounds, natural products have distinguishing structural properties; indeed, researchers have begun to quantify and catalog the differences between the two classes of molecules. Measurable differences in the number of chiral centers, the degree of saturation, the presence of aromatic rings, and the number of the various heteroatoms are among the chief distinctions between natural and synthetic compounds. Natural products also include a significant proportion of recurring molecular scaffolds that are not present in currently marketed drugs: the bioactivity of these natural substructures has been refined over the long process of evolution. In this Account, we present our research aimed at preparing libraries of semisynthetic compounds, or chemically engineered extracts (CEEs), through chemical diversification of natural products mixtures. The approach relies on the power of numbers, that is, in the chemical alteration of a sizable fraction of the starting complex mixture. Major changes in composition can be achieved through the chemical transformation of reactive molecular fragments that are found in most natural products. If such fragments are common enough, their transformation represents an entry point for chemically altering a high proportion of the components of crude natural extracts. We have searched for common reactive fragments in the Dictionary of Natural Products (CRC Press) and identified several functional groups that are expected to be present in a large fraction of the components of an average natural crude extract. To date, we have used reactions that incorporate (i) nitrogen atoms through carbonyl groups, (ii) sulfur by transformation of -OH and amines, and (iii) bromine through double bonds and aromatic rings. The resulting CEEs had different composition and biomolecular properties than their natural progenitors. We isolated a semisynthetic β-glucosidase inhibitor from a CEE prepared by reaction with benzenesulfonyl chloride, an antifungal pyrazole from a CEE prepared by reaction with hydrazine, and an acetylcholinesterase inhibitor from a CEE prepared through bromination. Our results illustrate how biological activity can be generated through chemical diversification of natural product mixtures. Moreover, the level of control that can be asserted in the process by judicious design and experimental choices underscores the potential for further development of CEEs in both basic research and drug discovery.
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Affiliation(s)
- I. Ayelen Ramallo
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario and Instituto de Química de Rosario (Conicet-UNR), Suipacha 531, 2000 Rosario, Argentina
| | - Mario O. Salazar
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario and Instituto de Química de Rosario (Conicet-UNR), Suipacha 531, 2000 Rosario, Argentina
| | - Luciana Mendez
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario and Instituto de Química de Rosario (Conicet-UNR), Suipacha 531, 2000 Rosario, Argentina
| | - Ricardo L. E. Furlan
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario and Instituto de Química de Rosario (Conicet-UNR), Suipacha 531, 2000 Rosario, Argentina
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534
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535
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Hong J. Role of natural product diversity in chemical biology. Curr Opin Chem Biol 2011; 15:350-4. [PMID: 21489856 DOI: 10.1016/j.cbpa.2011.03.004] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Accepted: 03/15/2011] [Indexed: 12/31/2022]
Abstract
Through the natural selection process, natural products possess a unique and vast chemical diversity and have been evolved for optimal interactions with biological macromolecules. Owing to their diversity, target affinity, and specificity, natural products have demonstrated enormous potential as modulators of biomolecular function, been an essential source for drug discovery, and provided design principles for combinatorial library development.
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Affiliation(s)
- Jiyong Hong
- Department of Chemistry, Duke University, Durham, NC 27708, USA.
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536
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Quantifying structure and performance diversity for sets of small molecules comprising small-molecule screening collections. Proc Natl Acad Sci U S A 2011; 108:6817-22. [PMID: 21482810 DOI: 10.1073/pnas.1015024108] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Using a diverse collection of small molecules we recently found that compound sets from different sources (commercial; academic; natural) have different protein-binding behaviors, and these behaviors correlate with trends in stereochemical complexity for these compound sets. These results lend insight into structural features that synthetic chemists might target when synthesizing screening collections for biological discovery. We report extensive characterization of structural properties and diversity of biological performance for these compounds and expand comparative analyses to include physicochemical properties and three-dimensional shapes of predicted conformers. The results highlight additional similarities and differences between the sets, but also the dependence of such comparisons on the choice of molecular descriptors. Using a protein-binding dataset, we introduce an information-theoretic measure to assess diversity of performance with a constraint on specificity. Rather than relying on finding individual active compounds, this measure allows rational judgment of compound subsets as groups. We also apply this measure to publicly available data from ChemBank for the same compound sets across a diverse group of functional assays. We find that performance diversity of compound sets is relatively stable across a range of property values as judged by this measure, both in protein-binding studies and functional assays. Because building screening collections with improved performance depends on efficient use of synthetic organic chemistry resources, these studies illustrate an important quantitative framework to help prioritize choices made in building such collections.
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537
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Van Den Berg M, Gidijala L, Kiela J, Bovenberg R, Vander Keli I. Biosynthesis of active pharmaceuticals: β-lactam biosynthesis in filamentous fungi. Biotechnol Genet Eng Rev 2011; 27:1-32. [PMID: 21415891 DOI: 10.1080/02648725.2010.10648143] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
β-lactam antibiotics (e.g. penicillins, cephalosporins) are of major clinical importance and contribute to over 40% of the total antibiotic market. These compounds are produced as secondary metabolites by certain actinomycetes and filamentous fungi (e.g. Penicillium, Aspergillus and Acremonium species). The industrial producer of penicillin is the fungus Penicillium chrysogenum. The enzymes of the penicillin biosynthetic pathway are well characterized and most of them are encoded by genes that are organized in a cluster in the genome. Remarkably, the penicillin biosynthetic pathway is compartmentalized: the initial steps of penicillin biosynthesis are catalyzed by cytosolic enzymes, whereas the two final steps involve peroxisomal enzymes. Here, we describe the biochemical properties of the enzymes of β-lactam biosynthesis in P. chrysogenum and the role of peroxisomes in this process. An overview is given on strain improvement programs via classical mutagenesis and, more recently, genetic engineering, leading to more productive strains. Also, the potential of using heterologous hosts for the development of novel ß-lactam antibiotics and non-ribosomal peptide synthetase-based peptides is discussed.
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Affiliation(s)
- Marco Van Den Berg
- Molecular Cell Biology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), Kluyver Center for Genomics of Industrial Fermentation, University of Groningen, The Netherlands.
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538
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Challenges and perspectives of chemical biology, a successful multidisciplinary field of natural sciences. Molecules 2011; 16:2672-87. [PMID: 21441869 PMCID: PMC6259834 DOI: 10.3390/molecules16032672] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Revised: 03/09/2011] [Accepted: 03/15/2011] [Indexed: 12/17/2022] Open
Abstract
Objects, goals, and main methods as well as perspectives of chemical biology are discussed. This review is focused on the fundamental aspects of this emerging field of life sciences: chemical space, the small molecule library and chemical sensibilization (small molecule microassays).
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539
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Ginsburg H, Deharo E. A call for using natural compounds in the development of new antimalarial treatments - an introduction. Malar J 2011; 10 Suppl 1:S1. [PMID: 21411010 PMCID: PMC3059457 DOI: 10.1186/1475-2875-10-s1-s1] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Natural compounds, mostly from plants, have been the mainstay of traditional medicine for thousands of years. They have also been the source of lead compounds for modern medicine, but the extent of mining of natural compounds for such leads decreased during the second half of the 20th century. The advantage of natural compounds for the development of drugs derives from their innate affinity for biological receptors. Natural compounds have provided the best anti-malarials known to date. Recent surveys have identified many extracts of various organisms (mostly plants) as having antiplasmodial activity. Huge libraries of fractionated natural compounds have been screened with impressive hit rates. Importantly, many cases are known where the crude biological extract is more efficient pharmacologically than the most active purified compound from this extract. This could be due to synergism with other compounds present in the extract, that as such have no pharmacological activity. Indeed, such compounds are best screened by cell-based assay where all potential targets in the cell are probed and possible synergies identified. Traditional medicine uses crude extracts. These have often been shown to provide many concoctions that deal better with the overall disease condition than with the causative agent itself. Traditional medicines are used by ~80 % of Africans as a first response to ailment. Many of the traditional medicines have demonstrable anti-plasmodial activities. It is suggested that rigorous evaluation of traditional medicines involving controlled clinical trials in parallel with agronomical development for more reproducible levels of active compounds could improve the availability of drugs at an acceptable cost and a source of income in malaria endemic countries.
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Affiliation(s)
- Hagai Ginsburg
- Dept, Biol, Chem, Inst, Life Sci, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
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540
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Méndez L, Salazar MO, Ramallo IA, Furlan RLE. Brominated extracts as source of bioactive compounds. ACS COMBINATORIAL SCIENCE 2011; 13:200-4. [PMID: 21395346 DOI: 10.1021/co100073k] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The chemical composition and the biomolecular properties of a crude plant extract were altered through bromination leading to the discovery of an acetylcholinesterase inhibitor.
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541
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Investigation of some medicinal plants traditionally used for treatment of malaria in Kenya as potential sources of antimalarial drugs. Exp Parasitol 2011; 127:609-26. [DOI: 10.1016/j.exppara.2010.11.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Revised: 11/01/2010] [Accepted: 11/09/2010] [Indexed: 11/23/2022]
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542
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Chen CH, Chou TW, Cheng LH, Ho CW. In vitro anti-adenoviral activity of five Allium plants. J Taiwan Inst Chem Eng 2011. [DOI: 10.1016/j.jtice.2010.07.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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543
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Santra S, Andreana PR. A Rapid, One-Pot, Microwave-Influenced Synthesis of Spiro-2,5-diketopiperazines via a Cascade Ugi/6-Exo-Trig Aza-Michael Reaction. J Org Chem 2011; 76:2261-4. [PMID: 21351784 DOI: 10.1021/jo102305q] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Soumava Santra
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
| | - Peter R. Andreana
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
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544
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Poulsen M, Oh DC, Clardy J, Currie CR. Chemical analyses of wasp-associated streptomyces bacteria reveal a prolific potential for natural products discovery. PLoS One 2011; 6:e16763. [PMID: 21364940 PMCID: PMC3043073 DOI: 10.1371/journal.pone.0016763] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Accepted: 01/13/2011] [Indexed: 11/19/2022] Open
Abstract
Identifying new sources for small molecule discovery is necessary to help mitigate the continuous emergence of antibiotic-resistance in pathogenic microbes. Recent studies indicate that one potentially rich source of novel natural products is Actinobacterial symbionts associated with social and solitary Hymenoptera. Here we test this possibility by examining two species of solitary mud dauber wasps, Sceliphron caementarium and Chalybion californicum. We performed enrichment isolations from 33 wasps and obtained more than 200 isolates of Streptomyces Actinobacteria. Chemical analyses of 15 of these isolates identified 11 distinct and structurally diverse secondary metabolites, including a novel polyunsaturated and polyoxygenated macrocyclic lactam, which we name sceliphrolactam. By pairing the 15 Streptomyces strains against a collection of fungi and bacteria, we document their antifungal and antibacterial activity. The prevalence and anti-microbial properties of Actinobacteria associated with these two solitary wasp species suggest the potential role of these Streptomyces as antibiotic-producing symbionts, potentially helping defend their wasp hosts from pathogenic microbes. Finding phylogenetically diverse and chemically prolific Actinobacteria from solitary wasps suggests that insect-associated Actinobacteria can provide a valuable source of novel natural products of pharmaceutical interest.
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Affiliation(s)
- Michael Poulsen
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Biology, Section for Ecology and Evolution, University of Copenhagen, Copenhagen, Denmark
| | - Dong-Chan Oh
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, United States of America
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, Republic of Korea
| | - Jon Clardy
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Cameron R. Currie
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- * E-mail:
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545
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Crawford AD, Liekens S, Kamuhabwa AR, Maes J, Munck S, Busson R, Rozenski J, Esguerra CV, de Witte PAM. Zebrafish bioassay-guided natural product discovery: isolation of angiogenesis inhibitors from East African medicinal plants. PLoS One 2011; 6:e14694. [PMID: 21379387 PMCID: PMC3040759 DOI: 10.1371/journal.pone.0014694] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Accepted: 09/12/2010] [Indexed: 01/10/2023] Open
Abstract
Natural products represent a significant reservoir of unexplored chemical diversity for early-stage drug discovery. The identification of lead compounds of natural origin would benefit from therapeutically relevant bioassays capable of facilitating the isolation of bioactive molecules from multi-constituent extracts. Towards this end, we developed an in vivo bioassay-guided isolation approach for natural product discovery that combines bioactivity screening in zebrafish embryos with rapid fractionation by analytical thin-layer chromatography (TLC) and initial structural elucidation by high-resolution electrospray mass spectrometry (HRESIMS). Bioactivity screening of East African medicinal plant extracts using fli-1:EGFP transgenic zebrafish embryos identified Oxygonum sinuatum and Plectranthus barbatus as inhibiting vascular development. Zebrafish bioassay-guided fractionation identified the active components of these plants as emodin, an inhibitor of the protein kinase CK2, and coleon A lactone, a rare abietane diterpenoid with no previously described bioactivity. Both emodin and coleon A lactone inhibited mammalian endothelial cell proliferation, migration, and tube formation in vitro, as well as angiogenesis in the chick chorioallantoic membrane (CAM) assay. These results suggest that the combination of zebrafish bioassays with analytical chromatography methods is an effective strategy for the rapid identification of bioactive natural products.
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Affiliation(s)
| | - Sandra Liekens
- Rega Institute for Medical Research, University of Leuven, Leuven, Belgium
- Department of Microbiology and Immunology, University of Leuven, Leuven, Belgium
| | - Appolinary R. Kamuhabwa
- Department of Pharmacognosy, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Jan Maes
- Department of Pharmaceutical Sciences, University of Leuven, Leuven, Belgium
| | - Sebastian Munck
- Department of Human Genetics, Flanders Interuniversity Institute of Biotechnology, University of Leuven, Leuven, Belgium
| | - Roger Busson
- Department of Pharmaceutical Sciences, University of Leuven, Leuven, Belgium
- Rega Institute for Medical Research, University of Leuven, Leuven, Belgium
| | - Jef Rozenski
- Department of Pharmaceutical Sciences, University of Leuven, Leuven, Belgium
- Rega Institute for Medical Research, University of Leuven, Leuven, Belgium
| | - Camila V. Esguerra
- Department of Pharmaceutical Sciences, University of Leuven, Leuven, Belgium
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546
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Mothana RAA, Kriegisch S, Harms M, Wende K, Lindequist U. Assessment of selected Yemeni medicinal plants for their in vitro antimicrobial, anticancer, and antioxidant activities. PHARMACEUTICAL BIOLOGY 2011; 49:200-210. [PMID: 20942618 DOI: 10.3109/13880209.2010.512295] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
CONTEXT The role of natural products as a source for remedies has been recognized since the beginning of mankind. Nevertheless, a minority of folkloricly used medicinal plants have been evaluated for their pharmacological activities. OBJECTIVES The purpose of this study is to evaluate 33 selected Yemeni plants for their in vitro anticancer, antimicrobial, and antioxidant activities. MATERIALS AND METHODS The plants were extracted with methanol and hot water. The obtained 66 extracts were tested for their in vitro cytotoxic activity using the neutral red uptake assay against two cancer cell lines (5637 and MCF-7). The antimicrobial activity was determined using the agar diffusion method and MIC-determination. The DPPH radical method was used for the determination of antioxidant activity. RESULTS Interesting cytotoxic activity was observed for Hypoestes forskalei (Vahl) R. Br. (Acanthaceae), Lycium shawii Roem. & Schult. (Solanaceae), Pergularia tomentosa L. (Asclepiadaceae), Psiadia punctulata (DC.) Vatke (Compositae), Pulicaria petiolaris Jaub. & Spach (Compositae) and Rosmarinus officinalis L. (Labiatae) (IC(50) values < 50 μg/mL). Antimicrobial activity with MIC values ≤ 125 μg/mL was exhibited against Gram-positive bacteria by Chrozophora oblongifolia (Del.) A.Juss. ex Spreng. (Euphorbiaceae), Myrtus communis L. (Myrtaceae), Phragmanthera regularis (Steud. ex Sprague) M.G. Gilbert (Loranthaceae) and R. officinalis. Antioxidant activity was observed for C. oblongifolia, M. communis, and P. regularis. CONCLUSION The results justified the use of some investigated plants in the Yemeni ethnomedicine. These findings demonstrated that some of the investigated plants could be a source of new cytotoxic and antibiotic compounds; however, further work is needed.
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Affiliation(s)
- Ramzi A A Mothana
- Department of Pharmacognosy, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
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547
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Odendaal AY, Trader DJ, Carlson EE. Chemoselective enrichment for natural products discovery. Chem Sci 2011; 2:760-764. [PMID: 24926410 DOI: 10.1039/c0sc00620c] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Natural products account for a significant proportion of modern day therapeutic agents. However, the discovery of novel compounds is hindered by the isolation process, which often relies upon extraction and chromatographic separation techniques. These methods, which are dependent upon the physicochemical properties of the compounds, have a limited ability to both purify and concentrate the minor components of a biological extract. We have devised an isolation strategy based upon an orthogonal chemical feature, namely, functional group composition. Development of a functional group-targeted method is expected to achieve exceptional resolution given the large number of distinct moieties present in natural product extracts. Here, we describe the generation of controllably reversible covalent enrichment tags for the chemoselective isolation of alcohol-containing natural products from complex mixtures.
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Affiliation(s)
- Antoinette Y Odendaal
- Department of Chemistry, Indiana University, 212 S. Hawthorne Dr, Bloomington, IN, 47401, USA
| | - Darci J Trader
- Department of Chemistry, Indiana University, 212 S. Hawthorne Dr, Bloomington, IN, 47401, USA
| | - Erin E Carlson
- Department of Chemistry, Indiana University, 212 S. Hawthorne Dr, Bloomington, IN, 47401, USA.,Department of Molecular and Cellular Biochemistry, Indiana University, 212 S. Hawthorne Dr, Bloomington, IN, 47401, USA
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548
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Abstract
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Small-molecule target identification is a vital and daunting task for the chemical biology community as well as for researchers interested in applying the power of chemical genetics to impact biology and medicine. To overcome this “target ID” bottleneck, new technologies are being developed that analyze protein–drug interactions, such as drug affinity responsive target stability (DARTS), which aims to discover the direct binding targets (and off targets) of small molecules on a proteome scale without requiring chemical modification of the compound. Here, we review the DARTS method, discuss why it works, and provide new perspectives for future development in this area.
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Affiliation(s)
- Brett Lomenick
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California 90095, United States
| | - Richard W. Olsen
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California 90095, United States
| | - Jing Huang
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California 90095, United States
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549
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Hou X, Wang S, Hou J, He L. Establishment of A431 cell membrane chromatography-RPLC method for screening target components from Radix Caulophylli. J Sep Sci 2011; 34:508-13. [DOI: 10.1002/jssc.201000643] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2010] [Revised: 12/05/2010] [Accepted: 12/06/2010] [Indexed: 11/11/2022]
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550
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Abstract
The synthesis of 3-acyltetramic acids, the substructure of bioactive natural products, via O-acylation of tetramic acids with carboxylic acids followed by acyl migration, has been investigated. This acylation sequence is mediated by N,N'-dicyclohexylcarbodiimide (DCC) and 4-dimethylaminopyridine (DMAP) and is very sensitive to the nature of the nitrogen substituent (R(1)), the nature of the carboxylic acid (R(2)CO(2)H), and the amount of DMAP. Acylation of N-acyl tetramic acids with an alkyl carboxylic acid using 1.3 equiv of DMAP (with 1.1 equiv of DCC) unexpectedly gave the 3-acyltetramic acid directly as a result of acyl migration induced by excess amounts of DMAP. On the other hand, N-unsubstituted, N-alkyl, and N-acyl tetramic acids with alkyl and aromatic carboxylic acids gave the O-acyl tetramic acids by using only 0.1 equiv of DMAP (with 1.1 equiv of DCC); these could be further rearranged to the acyl product by treatment with excess DMAP. The tautomeric equilibrium of these 3-acyltetramic acids in solution was found to strongly depend on the nitrogen substituent group (R(1)) rather than the 3-acyl group.
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Affiliation(s)
- Yong-Chul Jeong
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Rd, Oxford OX1 3TA, UK
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