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Georg M, Laping LA, Billo V, Gatto B, Friedhoff P, Göttlich R. Secondary 3-Chloropiperidines: Powerful Alkylating Agents. ChemistryOpen 2024; 13:e202300181. [PMID: 38088585 PMCID: PMC11164021 DOI: 10.1002/open.202300181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 10/15/2023] [Indexed: 06/11/2024] Open
Abstract
In previous works, we demonstrated that tertiary 3-chloropiperidines are potent chemotherapeutics, alkylating the DNA through the formation of bicyclic aziridinium ions. Herein, we report the synthesis of novel secondary 3-chloropiperidine analogues. The synthesis incorporates a new procedure to monochlorinate unsaturated primary amines utilizing N-chlorosuccinimide, while carefully monitoring the temperature to prevent dichlorination. Furthermore, we successfully isolated highly strained bicyclic aziridines by treating the secondary 3-chloropiperidines with a sufficient amount of base. We conclude this work with a DNA cleavage assay as a proof of principle, comparing our previously known substrates to the novel compounds. In this, the secondary 3-chloropiperidine as well as the isolated bicyclic aziridine, proved to be more effective than their tertiary counterpart.
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Affiliation(s)
- Mats Georg
- Institute of Organic ChemistryJustus Liebig University GiessenHeinrich-Buff-Ring 1735392GiessenGermany
| | - Lina Alexandra Laping
- Institute of Organic ChemistryJustus Liebig University GiessenHeinrich-Buff-Ring 1735392GiessenGermany
| | - Veronica Billo
- Institute of Organic ChemistryJustus Liebig University GiessenHeinrich-Buff-Ring 1735392GiessenGermany
- Department of Pharmaceutical and Pharmacological SciencesUniversity of PadovaPadovaItaly
| | - Barbara Gatto
- Department of Pharmaceutical and Pharmacological SciencesUniversity of PadovaPadovaItaly
| | - Peter Friedhoff
- Institute of BiochemistryJustus Liebig University GiessenHeinrich-Buff-Ring 1735392GiessenGermany
| | - Richard Göttlich
- Institute of Organic ChemistryJustus Liebig University GiessenHeinrich-Buff-Ring 1735392GiessenGermany
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2
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Dam D, Lagerweij NR, Janmaat KM, Kok K, Bouwman E, Codée JDC. Organic Dye-Sensitized Nitrene Generation: Intermolecular Aziridination of Unactivated Alkenes. J Org Chem 2024; 89:3251-3258. [PMID: 38358354 PMCID: PMC10913034 DOI: 10.1021/acs.joc.3c02709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/19/2024] [Accepted: 02/05/2024] [Indexed: 02/16/2024]
Abstract
Aziridines are important structural motifs and intermediates, and several synthetic strategies for the direct aziridination of alkenes have been introduced. However, many of these strategies require an excess of activated alkene, suffer from competing side-reactions, have limited functional group tolerance, or involve precious transition metal-based catalysts. Herein, we demonstrate the direct aziridination of alkenes by combining sulfonyl azides as a triplet nitrene source with a catalytic amount of an organic dye functioning as photosensitizer. We show how the nature of the sulfonyl azide, in combination with the triplet-excited state energy of the photosensitizer, affects the aziridination yield and provide a mechanistic rationale to account for the observed dependence of the reaction yield on the nature of the organic dye and sulfonyl azide reagents. The optimized reaction conditions enable the aziridination of structurally diverse and complex alkenes, carrying various functional groups, with the alkene as the limiting reagent.
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Affiliation(s)
- Dennis Dam
- Leiden Institute of Chemistry, Universiteit
Leiden, Leiden 2333 CC, The Netherlands
| | - Nathan R. Lagerweij
- Leiden Institute of Chemistry, Universiteit
Leiden, Leiden 2333 CC, The Netherlands
| | - Katharina M. Janmaat
- Leiden Institute of Chemistry, Universiteit
Leiden, Leiden 2333 CC, The Netherlands
| | - Ken Kok
- Leiden Institute of Chemistry, Universiteit
Leiden, Leiden 2333 CC, The Netherlands
| | - Elisabeth Bouwman
- Leiden Institute of Chemistry, Universiteit
Leiden, Leiden 2333 CC, The Netherlands
| | - Jeroen D. C. Codée
- Leiden Institute of Chemistry, Universiteit
Leiden, Leiden 2333 CC, The Netherlands
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3
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Aldeguer-Riquelme B, Antón J, Santos F. Distribution, abundance, and ecogenomics of the Palauibacterales, a new cosmopolitan thiamine-producing order within the Gemmatimonadota phylum. mSystems 2023; 8:e0021523. [PMID: 37345931 PMCID: PMC10469786 DOI: 10.1128/msystems.00215-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Accepted: 04/19/2023] [Indexed: 06/23/2023] Open
Abstract
The phylum Gemmatimonadota comprises mainly uncultured microorganisms that inhabit different environments such as soils, freshwater lakes, marine sediments, sponges, or corals. Based on 16S rRNA gene studies, the group PAUC43f is one of the most frequently retrieved Gemmatimonadota in marine samples. However, its physiology and ecological roles are completely unknown since, to date, not a single PAUC43f isolate or metagenome-assembled genome (MAG) has been characterized. Here, we carried out a broad study of the distribution, abundance, ecotaxonomy, and metabolism of PAUC43f, for which we propose the name of Palauibacterales. This group was detected in 4,965 16S rRNA gene amplicon datasets, mainly from marine sediments, sponges, corals, soils, and lakes, reaching up to 34.3% relative abundance, which highlights its cosmopolitan character, mainly salt-related. The potential metabolic capabilities inferred from 52 Palauibacterales MAGs recovered from marine sediments, sponges, and saline soils suggested a facultative aerobic and chemoorganotrophic metabolism, although some members may also oxidize hydrogen. Some Palauibacterales species might also play an environmental role as N2O consumers as well as suppliers of serine and thiamine. When compared to the rest of the Gemmatimonadota phylum, the biosynthesis of thiamine was one of the key features of the Palauibacterales. Finally, we show that polysaccharide utilization loci (PUL) are widely distributed within the Gemmatimonadota so that they are not restricted to Bacteroidetes, as previously thought. Our results expand the knowledge about this cryptic phylum and provide new insights into the ecological roles of the Gemmatimonadota in the environment. IMPORTANCE Despite advances in molecular and sequencing techniques, there is still a plethora of unknown microorganisms with a relevant ecological role. In the last years, the mostly uncultured Gemmatimonadota phylum is attracting scientific interest because of its widespread distribution and abundance, but very little is known about its ecological role in the marine ecosystem. Here we analyze the global distribution and potential metabolism of the marine Gemmatimonadota group PAUC43f, for which we propose the name of Palauibacterales order. This group presents a saline-related character and a chemoorganoheterotrophic and facultatively aerobic metabolism, although some species might oxidize H2. Given that Palauibacterales is potentially able to synthesize thiamine, whose auxotrophy is the second most common in the marine environment, we propose Palauibacterales as a key thiamine supplier to the marine communities. This finding suggests that Gemmatimonadota could have a more relevant role in the marine environment than previously thought.
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Affiliation(s)
- Borja Aldeguer-Riquelme
- Department of Physiology, Genetics, and Microbiology, University of Alicante, Alicante, Spain
| | - Josefa Antón
- Department of Physiology, Genetics, and Microbiology, University of Alicante, Alicante, Spain
- Multidisciplinary Institute of Environmental Studies Ramón Margalef, University of Alicante, Alicante, Spain
| | - Fernando Santos
- Department of Physiology, Genetics, and Microbiology, University of Alicante, Alicante, Spain
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4
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Klarek M, Siodła T, Ayad T, Virieux D, Rapp M. Access to 2-Fluorinated Aziridine-2-phosphonates from α, α-Halofluorinated β-Iminophosphonates-Spectroscopic and Theoretical Studies. Molecules 2023; 28:5579. [PMID: 37513451 PMCID: PMC10385471 DOI: 10.3390/molecules28145579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 07/16/2023] [Accepted: 07/20/2023] [Indexed: 07/30/2023] Open
Abstract
The efficient one-pot halofluorination of a β-enaminophosphonate/β-iminophosphonate tautomeric mixture resulting in α,α-halofluorinated β-iminophosphonates is reported. Subsequent imine reduction gave the corresponding β-aminophosphonates as a racemic mixture or with high diastereoselectivity. The proposed protocol is the first example of a synthesis of N-inactivated aziridines substituted by a fluorine and phosphonate moiety on the same carbon atom. Based on spectroscopic and theoretical studies, we determined the cis/trans geometry of the resulting fluorinated aziridine-2-phosphonate. Our procedure, involving the reduction of cis/trans-fluoroaziridine mixture 24, allows us to isolate chiral trans-aziridines 24 as well as cis-aziridines 27 that do not contain a fluorine atom. We also investigated the influence of the fluorine atom on the reactivity of aziridine through an acid-catalyzed regioselective ring-opening reaction. The results of DFT calculations, at the PCM/ωB97x-D/def2-TZVPD level of theory, are in good agreement with the experiments. The transition states of the SN2 intramolecular cyclization of vicinal haloamines have been modeled.
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Affiliation(s)
- Mateusz Klarek
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland
| | - Tomasz Siodła
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland
| | - Tahar Ayad
- Institut Charles Gerhardt, CNRS, Ecole Nationale Supérieure de Chimie de Montpellier, 8 Rue de l'Ecole Normale, 34296 Montpellier, France
| | - David Virieux
- Institut Charles Gerhardt, CNRS, Ecole Nationale Supérieure de Chimie de Montpellier, 8 Rue de l'Ecole Normale, 34296 Montpellier, France
| | - Magdalena Rapp
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland
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5
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Zill NA, Du Y, Marinkovich S, Gu D, Seidel J, Zhang W. Bioactive Natural Product Discovery via Deuterium Adduct Bioactivity Screening. ACS Chem Biol 2023; 18:1192-1199. [PMID: 37125845 DOI: 10.1021/acschembio.3c00083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The discovery of bioactive natural products lies at the forefront of human medicine. The continued discovery of these molecules is imperative in the fight against infection and disease. While natural products have historically dominated the drug market, discovery in recent years has slowed significantly, partly due to limitations in current discovery methodologies. This work demonstrates a new workflow, deuterium adduct bioactivity screening (DABS), which pairs untargeted isotope labeling with whole cell binding assays for bioactive natural product discovery. DABS was validated and led to the discovery of a new isoprenyl guanidine alkaloid, zillamycin, which showed anti-cancer and anti-microbial activities. DABS thus represents a new workflow to accelerate discovery of natural products with a wide range of bioactive potentials.
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Affiliation(s)
- Nicholas A Zill
- Department of Chemical and Biomolecular Engineering, University of California Berkeley, Berkeley, California 94720, United States
| | - Yongle Du
- California Institute for Quantitative Biosciences, University of California Berkeley, Berkeley, California 94720, United States
| | - Samantha Marinkovich
- Department of Chemical and Biomolecular Engineering, University of California Berkeley, Berkeley, California 94720, United States
| | - Di Gu
- Department of Chemistry, University of California Berkeley, Berkeley, California 94720, United States
| | - Jeremy Seidel
- Department of Chemical and Biomolecular Engineering, University of California Berkeley, Berkeley, California 94720, United States
| | - Wenjun Zhang
- Department of Chemical and Biomolecular Engineering, University of California Berkeley, Berkeley, California 94720, United States
- California Institute for Quantitative Biosciences, University of California Berkeley, Berkeley, California 94720, United States
- Hong Kong Branch of the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong 999077, China
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6
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Trocha A, Piotrowska DG, Głowacka IE. Synthesis of Enantiomerically Enriched Protected 2-Amino-, 2,3-Diamino- and 2-Amino-3-Hydroxypropylphosphonates. Molecules 2023; 28:molecules28031466. [PMID: 36771131 PMCID: PMC9921368 DOI: 10.3390/molecules28031466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 02/01/2023] [Accepted: 02/01/2023] [Indexed: 02/05/2023] Open
Abstract
Simple and efficient strategies for the syntheses of enantiomerically enriched functionalized diethyl 2-amino-, 2,3-diamino- and 2-amino-3-hydroxypropylphosphonates have been developed starting from, respectively, N-protected (aziridin-2-yl)methylphosphonates, employing a regioselective aziridine ring-opening reaction with corresponding nucleophiles. Diethyl (R)- and (S)-2-(N-Boc-amino)propylphosphonates were obtained via direct regiospecific hydrogenolysis of the respective enantiomer of (R)- and (S)-N-Boc-(aziridin-2-yl)methylphosphonates. N-Boc-protected (R)- and (S)-2,3-diaminopropylphosphonates were synthesized from (R)- and (S)-N-Bn-(aziridin-2-yl)methylphosphonates via a regiospecific ring-opening reaction with neat trimethylsilyl azide and subsequent reduction of (R)- and (S)-2-(N-Boc-amino)-3-azidopropylphosphonates using triphenylphosphine. On the other hand, treatment of the corresponding (R)- and (S)-N-Bn-(aziridin-2-yl)methylphosphonates with glacial acetic acid led regiospecifically to the formation of (R)- and (S)-2-(N-Bn-amino)-3-acetoxypropylphosphonates.
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7
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Qiu M, Fu X, Fu P, Huang J. Construction of aziridine, azetidine, indole and quinoline-like heterocycles via Pd-mediated C-H activation/annulation strategies. Org Biomol Chem 2022; 20:1339-1359. [PMID: 35044404 DOI: 10.1039/d1ob02146j] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
N-Heterocycles can be found in natural products and drug molecules and are indispensable components in the area of organic synthesis, medicinal chemistry and materials science. The construction of these N-containing heterocycles by traditional methods usually requires the preparation of reactive intermediates. In the past decades, with the rapid growth of transition metal catalysed coupling reactions, syntheses of heterocycles from precursors with inert chemical bonds have become a challenge. More recently, in the field of transition metal associated C-H direct functionalization, efficient methods have been developed for the syntheses of N-heterocyclic compounds such as aziridines, azetidines, indoles and quinolines under the click type of reaction mode. In this review, representative synthetic methodologies developed in the recent 10 years for the preparation of this small class of N-heterocycles via the Pd-catalysed C-H activation and C-N bond formation pathway are discussed. We hope this article will provide new insights from the strategies highlighted into future molecular design, synthesis and applications in medical and materials sciences.
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Affiliation(s)
- Mengyu Qiu
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China. .,Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, China.,Tianjin University and Health-Biotech United Group Joint Laboratory of Innovative Drug Development and Translational Medicine, China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | - Xuegang Fu
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China. .,Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, China.,Tianjin University and Health-Biotech United Group Joint Laboratory of Innovative Drug Development and Translational Medicine, China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | - Peng Fu
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China. .,Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, China.,Tianjin University and Health-Biotech United Group Joint Laboratory of Innovative Drug Development and Translational Medicine, China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | - Jianhui Huang
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China. .,Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, China.,Tianjin University and Health-Biotech United Group Joint Laboratory of Innovative Drug Development and Translational Medicine, China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
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8
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Washburn LA, Nepal KK, Watanabe CMH. A Capture Strategy for the Identification of Thio-Templated Metabolites. ACS Chem Biol 2021; 16:1737-1744. [PMID: 34423966 DOI: 10.1021/acschembio.1c00437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nonribosomal peptide synthetase and polyketide synthase systems are home to complex enzymology and produce compounds of great therapeutic value. Despite this, they have continued to be difficult to characterize due to their substrates remaining enzyme-bound by a thioester bond. Here, we have developed a strategy to directly trap and characterize the thioester-bound enzyme intermediates and applied the strategy to the azinomycin biosynthetic pathway. The approach was initially applied in vitro to evaluate its efficacy and subsequently moved to an in situ system, where a protein of interest was isolated from the native organism to avoid needing to supply substrates. When the nonribosomal peptide synthetase AziA3 was isolated from Streptomyces sahachiroi, the capture strategy revealed AziA3 functions in the late stages of epoxide moiety formation of the azinomycins. The strategy was further validated in vitro with a nonribosomal peptide synthetase involved in colibactin biosynthesis. In the long term, this method will be utilized to characterize thioester-bound metabolites within not only the azinomycin biosynthetic pathway but also other cryptic metabolite pathways.
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Affiliation(s)
- Lauren A. Washburn
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Keshav K. Nepal
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Coran M. H. Watanabe
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
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9
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Warren GM, Wang J, Patel DJ, Shuman S. Oligomeric quaternary structure of Escherichia coli and Mycobacterium smegmatis Lhr helicases is nucleated by a novel C-terminal domain composed of five winged-helix modules. Nucleic Acids Res 2021; 49:3876-3887. [PMID: 33744958 PMCID: PMC8053096 DOI: 10.1093/nar/gkab145] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/18/2021] [Accepted: 02/23/2021] [Indexed: 11/29/2022] Open
Abstract
Mycobacterium smegmatis Lhr (MsmLhr; 1507-aa) is the founder of a novel clade of bacterial helicases. MsmLhr consists of an N-terminal helicase domain (aa 1–856) with a distinctive tertiary structure (Lhr-Core) and a C-terminal domain (Lhr-CTD) of unknown structure. Here, we report that Escherichia coli Lhr (EcoLhr; 1538-aa) is an ATPase, translocase and ATP-dependent helicase. Like MsmLhr, EcoLhr translocates 3′ to 5′ on ssDNA and unwinds secondary structures en route, with RNA:DNA hybrid being preferred versus DNA:DNA duplex. The ATPase and translocase activities of EcoLhr inhere to its 877-aa Core domain. Full-length EcoLhr and MsmLhr have homo-oligomeric quaternary structures in solution, whereas their respective Core domains are monomers. The MsmLhr CTD per se is a homo-oligomer in solution. We employed cryo-EM to solve the structure of the CTD of full-length MsmLhr. The CTD protomer is composed of a series of five winged-helix (WH) modules and a β-barrel module. The CTD adopts a unique homo-tetrameric quaternary structure. A Lhr-CTD subdomain, comprising three tandem WH modules and the β-barrel, is structurally homologous to AlkZ, a bacterial DNA glycosylase that recognizes and excises inter-strand DNA crosslinks. This homology is noteworthy given that Lhr is induced in mycobacteria exposed to the inter-strand crosslinker mitomycin C.
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Affiliation(s)
- Garrett M Warren
- Molecular Biology and Structural Biology Programs, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Juncheng Wang
- Molecular Biology and Structural Biology Programs, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Dinshaw J Patel
- Molecular Biology and Structural Biology Programs, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Stewart Shuman
- Molecular Biology and Structural Biology Programs, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
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10
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Mohan CD, Rangappa S, Nayak SC, Jadimurthy R, Wang L, Sethi G, Garg M, Rangappa KS. Bacteria as a treasure house of secondary metabolites with anticancer potential. Semin Cancer Biol 2021; 86:998-1013. [PMID: 33979675 DOI: 10.1016/j.semcancer.2021.05.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 05/03/2021] [Accepted: 05/03/2021] [Indexed: 12/27/2022]
Abstract
Cancer stands in the frontline among leading killers worldwide and the annual mortality rate is expected to reach 16.4 million by 2040. Humans suffer from about 200 different types of cancers and many of them have a small number of approved therapeutic agents. Moreover, several types of major cancers are diagnosed at advanced stages as a result of which the existing therapies have limited efficacy against them and contribute to a dismal prognosis. Therefore, it is essential to develop novel potent anticancer agents to counteract cancer-driven lethality. Natural sources such as bacteria, plants, fungi, and marine microorganisms have been serving as an inexhaustible source of anticancer agents. Notably, over 13,000 natural compounds endowed with different pharmacological properties have been isolated from different bacterial sources. In the present article, we have discussed about the importance of natural products, with special emphasis on bacterial metabolites for cancer therapy. Subsequently, we have comprehensively discussed the various sources, mechanisms of action, toxicity issues, and off-target effects of clinically used anticancer drugs (such as actinomycin D, bleomycin, carfilzomib, doxorubicin, ixabepilone, mitomycin C, pentostatin, rapalogs, and romidepsin) that have been derived from different bacteria. Furthermore, we have also discussed some of the major secondary metabolites (antimycins, chartreusin, elsamicins, geldanamycin, monensin, plicamycin, prodigiosin, rebeccamycin, salinomycin, and salinosporamide) that are currently in the clinical trials or which have demonstrated potent anticancer activity in preclinical models. Besides, we have elaborated on the application of metagenomics in drug discovery and briefly described about anticancer agents (bryostatin 1 and ET-743) identified through the metagenomics approach.
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Affiliation(s)
| | - Shobith Rangappa
- Adichunchanagiri Institute for Molecular Medicine, Adichunchanagiri University, BG Nagara, 571448, Nagamangala Taluk, India
| | - S Chandra Nayak
- Department of Studies in Biotechnology, University of Mysore, Manasagangotri, Mysore, 570006, India
| | - Ragi Jadimurthy
- Department of Studies in Molecular Biology, University of Mysore, Manasagangotri, Mysore, 570006, India
| | - Lingzhi Wang
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117600, Singapore; Cancer Science Institute of Singapore, National University of Singapore, Singapore, 117599, Singapore
| | - Gautam Sethi
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117600, Singapore
| | - Manoj Garg
- Amity Institute of Molecular Medicine and Stem Cell Research, Amity University, Uttar Pradesh, Noida, 201313, India
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11
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Bradley NP, Washburn LA, Christov PP, Watanabe CMH, Eichman BF. Escherichia coli YcaQ is a DNA glycosylase that unhooks DNA interstrand crosslinks. Nucleic Acids Res 2020; 48:7005-7017. [PMID: 32409837 PMCID: PMC7367128 DOI: 10.1093/nar/gkaa346] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 04/17/2020] [Accepted: 04/23/2020] [Indexed: 12/12/2022] Open
Abstract
Interstrand DNA crosslinks (ICLs) are a toxic form of DNA damage that block DNA replication and transcription by tethering the opposing strands of DNA. ICL repair requires unhooking of the tethered strands by either nuclease incision of the DNA backbone or glycosylase cleavage of the crosslinked nucleotide. In bacteria, glycosylase-mediated ICL unhooking was described in Streptomyces as a means of self-resistance to the genotoxic natural product azinomycin B. The mechanistic details and general utility of glycosylase-mediated ICL repair in other bacteria are unknown. Here, we identify the uncharacterized Escherichia coli protein YcaQ as an ICL repair glycosylase that protects cells against the toxicity of crosslinking agents. YcaQ unhooks both sides of symmetric and asymmetric ICLs in vitro, and loss or overexpression of ycaQ sensitizes E. coli to the nitrogen mustard mechlorethamine. Comparison of YcaQ and UvrA-mediated ICL resistance mechanisms establishes base excision as an alternate ICL repair pathway in bacteria.
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Affiliation(s)
- Noah P Bradley
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37232, USA
| | - Lauren A Washburn
- Department of Chemistry, Texas A&M University, College Station, TX 77843, USA
| | - Plamen P Christov
- Institute of Chemical Biology, Vanderbilt University, Nashville, TN 37232, USA
| | - Coran M H Watanabe
- Department of Chemistry, Texas A&M University, College Station, TX 77843, USA
| | - Brandt F Eichman
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37232, USA.,Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA
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12
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Chen X, Sun Y, Wang S, Ying K, Xiao L, Liu K, Zuo X, He J. Identification of a novel structure-specific endonuclease AziN that contributes to the repair of azinomycin B-mediated DNA interstrand crosslinks. Nucleic Acids Res 2020; 48:709-718. [PMID: 31713613 PMCID: PMC7145581 DOI: 10.1093/nar/gkz1067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 10/11/2019] [Accepted: 10/30/2019] [Indexed: 11/25/2022] Open
Abstract
DNA interstrand crosslinks (ICLs) induced by the highly genotoxic agent azinomycin B (AZB) can cause severe perturbation of DNA structure and even cell death. However, Streptomyces sahachiroi, the strain that produces AZB, seems almost impervious to this danger because of its diverse and distinctive self-protection machineries. Here, we report the identification of a novel endonuclease-like gene aziN that contributes to drug self-protection in S. sahachiroi. AziN expression conferred AZB resistance on native and heterologous host strains. The specific binding reaction between AziN and AZB was also verified in accordance with its homology to drug binding proteins, but no drug sequestering and deactivating effects could be detected. Intriguingly, due to the high affinity with the drug, AziN was discovered to exhibit specific recognition and binding capacity with AZB-mediated ICL structures, further inducing DNA strand breakage. Subsequent in vitro assays demonstrated the structure-specific endonuclease activity of AziN, which cuts both damaged strands at specific sites around AZB-ICLs. Unravelling the nuclease activity of AziN provides a good entrance point to illuminate the complex mechanisms of AZB-ICL repair.
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Affiliation(s)
- Xiaorong Chen
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Yuedi Sun
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Shan Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Kun Ying
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Le Xiao
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Kai Liu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Xiuli Zuo
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Jing He
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
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13
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Washburn LA, Foley B, Martinez F, Lee RP, Pryor K, Rimes E, Watanabe CMH. Transketolase Activity in the Formation of the Azinomycin Azabicycle Moiety. Biochemistry 2019; 58:5255-5258. [DOI: 10.1021/acs.biochem.9b00477] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Lauren A. Washburn
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Brendan Foley
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Flor Martinez
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Rachel P. Lee
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Kendall Pryor
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Emily Rimes
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Coran M. H. Watanabe
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
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14
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Kelly GT, Washburn LA, Watanabe CMH. The Fate of Molecular Oxygen in Azinomycin Biosynthesis. J Org Chem 2019; 84:2991-2996. [PMID: 30680995 DOI: 10.1021/acs.joc.8b03007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The azinomycins are a family of aziridine-containing antitumor antibiotics and represent a treasure trove of biosynthetic reactions. The formation of the azabicyclo[3.1.0]hexane ring and functionalization of this ring system remain the least understood aspects of the pathway. This study reports the incorporation of 18O-labeled molecular oxygen in azinomycin biosynthesis including both oxygens of the diol that ultimately adorn the aziridino[1,2- a]pyrrolidine moiety. Likewise, two other sites of heavy atom incorporation are observed.
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Affiliation(s)
- Gilbert T Kelly
- Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
| | - Lauren A Washburn
- Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
| | - Coran M H Watanabe
- Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
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15
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Abstract
DNA glycosylases are important editing enzymes that protect genomic stability by excising chemically modified nucleobases that alter normal DNA metabolism. These enzymes have been known only to initiate base excision repair of small adducts by extrusion from the DNA helix. However, recent reports have described both vertebrate and microbial DNA glycosylases capable of unhooking highly toxic interstrand cross-links (ICLs) and bulky minor groove adducts normally recognized by Fanconi anemia and nucleotide excision repair machinery, although the mechanisms of these activities are unknown. Here we report the crystal structure of Streptomyces sahachiroi AlkZ (previously Orf1), a bacterial DNA glycosylase that protects its host by excising ICLs derived from azinomycin B (AZB), a potent antimicrobial and antitumor genotoxin. AlkZ adopts a unique fold in which three tandem winged helix-turn-helix motifs scaffold a positively charged concave surface perfectly shaped for duplex DNA. Through mutational analysis, we identified two glutamine residues and a β-hairpin within this putative DNA-binding cleft that are essential for catalytic activity. Additionally, we present a molecular docking model for how this active site can unhook either or both sides of an AZB ICL, providing a basis for understanding the mechanisms of base excision repair of ICLs. Given the prevalence of this protein fold in pathogenic bacteria, this work also lays the foundation for an emerging role of DNA repair in bacteria-host pathogenesis.
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16
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Mori S, Nepal KK, Kelly GT, Sharma V, Simkhada D, Gowda V, Delgado D, Watanabe CMH. Priming of Azabicycle Biosynthesis in the Azinomycin Class of Antitumor Agents. Biochemistry 2017; 56:805-808. [PMID: 28135072 DOI: 10.1021/acs.biochem.6b01108] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The biosynthesis of the azabicyclic ring system of the azinomycin family of antitumor agents represents the "crown jewel" of the pathway and is a complex process involving at least 14 enzymatic steps. This study reports on the first biosynthetic step, the inroads, in the construction of the novel aziridino [1,2-a]pyrrolidine, azabicyclic core, allowing us to support a new mechanism for azabicycle formation.
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Affiliation(s)
- Shogo Mori
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Keshav K Nepal
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Gilbert T Kelly
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Vasudha Sharma
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Dinesh Simkhada
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Vishruth Gowda
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Dioscar Delgado
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Coran M H Watanabe
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
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17
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Chen M, Liu J, Duan P, Li M, Liu W. Biosynthesis and molecular engineering of templated natural products. Natl Sci Rev 2016. [DOI: 10.1093/nsr/nww045] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Abstract
Bioactive small molecules that are produced by living organisms, often referred to as natural products (NPs), historically play a critical role in the context of both medicinal chemistry and chemical biology. How nature creates these chemical entities with stunning structural complexity and diversity using a limited range of simple substrates has not been fully understood. Focusing on two types of NPs that share a highly evolvable ‘template’-biosynthetic logic, we here provide specific examples to highlight the conceptual and technological leaps in NP biosynthesis and witness the area of progress since the beginning of the twenty-first century. The biosynthesis of polyketides, non-ribosomal peptides and their hybrids that share an assembly-line enzymology of modular multifunctional proteins exemplifies an extended ‘central dogma’ that correlates the genotype of catalysts with the chemotype of products; in parallel, post-translational modifications of ribosomally synthesized peptides involve a number of unusual biochemical mechanisms for molecular maturation. Understanding the biosynthetic processes of these templated NPs would largely facilitate the design, development and utilization of compatible biosynthetic machineries to address the challenge that often arises from structural complexity to the accessibility and efficiency of current chemical synthesis.
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Affiliation(s)
- Ming Chen
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| | - Jingyu Liu
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| | - Panpan Duan
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| | - Mulin Li
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| | - Wen Liu
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
- State Key Laboratory of Microbial Metabolism, School of Life Science & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
- Huzhou Center of Bio-Synthetic Innovation, Huzhou 313000, China
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18
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Nepal KK, Lee RP, Rezenom YH, Watanabe CMH. Probing the Role of N-Acetyl-glutamyl 5-Phosphate, an Acyl Phosphate, in the Construction of the Azabicycle Moiety of the Azinomycins. Biochemistry 2015; 54:4415-8. [DOI: 10.1021/acs.biochem.5b00711] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Keshav K. Nepal
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Rachel P. Lee
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Yohannes H. Rezenom
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Coran M. H. Watanabe
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
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19
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Abstract
α,β-Dehydroamino acids are naturally occurring non-coded amino acids, found primarily in peptides. The review focuses on the type of α,β-dehydroamino acids, the structure of dehydropeptides, the source of their origin and bioactivity. Dehydropeptides are isolated primarily from bacteria and less often from fungi, marine invertebrates or even higher plants. They reveal mainly antibiotic, antifungal, antitumour, and phytotoxic activity. More than 60 different structures were classified, which often cover broad families of peptides. 37 different structural units containing the α,β-dehydroamino acid residues were shown including various side chains, Z and E isomers, and main modifications: methylation of peptide bond as well as the introduction of ester group and heterocycle ring. The collected data show the relation between the structure and bioactivity. This allows the activity of compounds, which were not studied in this field, but which belong to a larger peptide family to be predicted. A few examples show that the type of the geometrical isomer of the α,β-dehydroamino acid residue can be important or even crucial for biological activity.
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Affiliation(s)
- Dawid Siodłak
- Faculty of Chemistry, University of Opole, Oleska, 48 45-052, Opole, Poland,
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20
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Wang Q, Zhang Z, Zhang X, Zhang J, Kang Y, Peng J. Synthesis of 7a-phenyl-1a,7a-dihydro-benzopyrano[2,3-b]azirin-7-ones via photoisomerization reaction. RSC Adv 2015. [DOI: 10.1039/c4ra12542h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
An environmentally friendly and novel protocol has been developed for the synthesis of 7a-phenyl-1a,7a-phenyl-benzopyrano[2,3-b]azirin-7-ones in moderate to high yieldsviathe photoisomerization of 4-phenyl-5-(2-hydroxyphenyl)isoxazoles.
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Affiliation(s)
- Qiuya Wang
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry
- National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China
- School of Chemistry and Chemical Engineering
- Shaanxi Normal University
- Xi'an 710062
| | - Zunting Zhang
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry
- National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China
- School of Chemistry and Chemical Engineering
- Shaanxi Normal University
- Xi'an 710062
| | - Xi Zhang
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry
- National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China
- School of Chemistry and Chemical Engineering
- Shaanxi Normal University
- Xi'an 710062
| | - Jin Zhang
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry
- National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China
- School of Chemistry and Chemical Engineering
- Shaanxi Normal University
- Xi'an 710062
| | - Yang Kang
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry
- National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China
- School of Chemistry and Chemical Engineering
- Shaanxi Normal University
- Xi'an 710062
| | - Jufang Peng
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry
- National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China
- School of Chemistry and Chemical Engineering
- Shaanxi Normal University
- Xi'an 710062
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21
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Vinader V, Sadiq M, Sutherland M, Huang M, Loadman PM, Elsalem L, Shnyder SD, Cui H, Afarinkia K, Searcey M, Patterson LH, Pors K. Probing cytochrome P450-mediated activation with a truncated azinomycin analogue. MEDCHEMCOMM 2015. [DOI: 10.1039/c4md00411f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Selective cytochrome P450 bioactivation of truncated azinomycin.
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Affiliation(s)
| | - Maria Sadiq
- Institute of Cancer Therapeutics
- University of Bradford
- UK
| | | | - Mengying Huang
- State Key Laboratory of Silkworm Genome Biology
- Southwest University
- Chongqing
- China
| | | | - Lina Elsalem
- Institute of Cancer Therapeutics
- University of Bradford
- UK
| | | | - Hongjuan Cui
- State Key Laboratory of Silkworm Genome Biology
- Southwest University
- Chongqing
- China
| | | | - Mark Searcey
- School of Pharmacy
- University of East Anglia
- Norwich NR4 7TJ
- UK
| | | | - Klaus Pors
- Institute of Cancer Therapeutics
- University of Bradford
- UK
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22
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Aziridines from alkenyl-β-D-galactopyranoside derivatives: Stereoselective synthesis and in vitro selective anticancer activity. Eur J Med Chem 2013; 70:380-92. [DOI: 10.1016/j.ejmech.2013.10.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 10/03/2013] [Accepted: 10/07/2013] [Indexed: 11/22/2022]
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23
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Senthilnathan D, Kalaiselvan A, Venuvanalingam P. Sequence selectivity of azinomycin B in DNA alkylation and cross-linking: a QM/MM study. J Mol Model 2012; 19:383-90. [PMID: 22930355 DOI: 10.1007/s00894-012-1557-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 08/01/2012] [Indexed: 10/28/2022]
Abstract
Azinomycin B--a well-known antitumor drug--forms cross-links with DNA through alkylation of purine bases and blocks tumor cell growth. This reaction has been modeled using the ONIOM (B3LYP/6-31+g(d):UFF) method to understand the mechanism and sequence selectivity. ONIOM results have been checked for reliability by comparing them with full quantum mechanics calculations for selected paths. Calculations reveal that, among the purine bases, guanine is more reactive and is alkylated by aziridine ring through the C10 position, followed by alkylation of the epoxide ring through the C21 position of Azinomycin B. While the mono alkylation is controlled kinetically, bis-alkylation is controlled thermodynamically. Solvent effects were included using polarized-continuum-model calculations and no significant change from gas phase results was observed.
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24
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Tanasova M, Sturla SJ. Chemistry and biology of acylfulvenes: sesquiterpene-derived antitumor agents. Chem Rev 2012; 112:3578-610. [PMID: 22482429 DOI: 10.1021/cr2001367] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marina Tanasova
- ETH Zurich, Institute of Food, Nutrition and Health, Zurich, Switzerland
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25
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Foulke-Abel J, Kelly GT, Zhang H, Watanabe CMH. Characterization of AziR, a resistance protein of the DNA cross-linking agent azinomycin B. MOLECULAR BIOSYSTEMS 2011; 7:2563-70. [DOI: 10.1039/c1mb05136a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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26
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Foulke-Abel J, Agbo H, Zhang H, Mori S, Watanabe CMH. Mode of action and biosynthesis of the azabicycle-containing natural products azinomycin and ficellomycin. Nat Prod Rep 2011; 28:693-704. [DOI: 10.1039/c0np00049c] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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27
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Synthesis and DNA cleavage evaluation of epoxypiperidine derivatives bearing a dehydroamino acid unit. Tetrahedron 2010. [DOI: 10.1016/j.tet.2010.08.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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28
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Ding W, Deng W, Tang M, Zhang Q, Tang G, Bi Y, Liu W. Biosynthesis of 3-methoxy-5-methyl naphthoic acid and its incorporation into the antitumor antibiotic azinomycin B. MOLECULAR BIOSYSTEMS 2010; 6:1071-81. [PMID: 20485749 DOI: 10.1039/b926358f] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Azinomycin B is a potent antitumor antibiotic that features a set of unusual, densely assembled functionalities. Among them, the 3-methoxy-5-methylnaphthoic acid (NPA) moiety provides an important noncovalent association with DNA, and may, therefore, contribute to the specificity of DNA alkylation for biological activity exhibition. We have previously cloned and sequenced the azinomycin B biosynthetic gene cluster, and proposed that four enzymes: AziB, AziB1, AziB2, and AziA1, are involved in the naphthoate moiety formation and incorporation. In this study, we report in vivo and/or in vitro characterizations of the P450 hydroxylase AziB1, the O-methyltransferase AziB2, and the substrate specificity of the non-ribosomal peptide synthetase (NRPS) AziA1, providing insights into the timing of individual steps in the late-stage modification of 5-methyl-NPA synthesized by the iterative type I polyketide synthase AziB. AziB1 catalyzes a regiospecific hydroxylation at the C3 position of the free naphthoic acid 5-methyl-NPA to produce 3-hydroxy-5-methyl-NPA, and the resulting hydroxyl group is subsequently O-methylated by AziB2 to furnish the methoxy functionality. The di-domain NRPS AziA1 specifically incorporates 3-methoxy-5-methyl-NPA via an unusual A domain to initiate the backbone formation of azinomycin B. AziA1 activates several analogues of the natural starter unit, suggesting a potential for production by metabolic engineering of new azinomycin analogues differing in their NPA moieties.
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Affiliation(s)
- Wei Ding
- School of Life Science, Lanzhou University, 222 South Tianshui Rd, Lanzhou 730000, China
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29
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Wróblewski AE, Szewczyk EM, Baôk-Sypień II. Synthesis of (1R,2R)- and (1S,2R)-1,2-Epoxy-3-hydroxypropylphosphonates as Analogues of Fosfomycin. Arch Pharm (Weinheim) 2009; 342:521-7. [DOI: 10.1002/ardp.200900044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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30
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Ismail FMD, Levitsky DO, Dembitsky VM. Aziridine alkaloids as potential therapeutic agents. Eur J Med Chem 2009; 44:3373-87. [PMID: 19540628 DOI: 10.1016/j.ejmech.2009.05.013] [Citation(s) in RCA: 161] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2008] [Revised: 05/13/2009] [Accepted: 05/14/2009] [Indexed: 10/20/2022]
Abstract
The present review describes research on natural aziridine alkaloids isolated from both terrestrial and marine species, as well as their lipophilic semi-synthetic, and/or synthetic analogs. Over 130 biologically active aziridine-containing compounds demonstrate confirmed pharmacological activity including antitumor, antimicrobial, antibacterial effects. The structures, origin, and biological activities of aziridine alkaloids are reviewed. Consequently this review emphasizes the role of aziridine alkaloids as an important source of drug prototypes and leads for drug discovery.
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Affiliation(s)
- Fyaz M D Ismail
- Medicinal Chemistry Research Group, Department of Pharmacy and Chemistry, Liverpool John Moores University, 221C Phase 1, Byrom Street, Liverpool, Merseyside L3 3AF, UK
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31
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Olano C, Méndez C, Salas JA. Antitumor compounds from actinomycetes: from gene clusters to new derivatives by combinatorial biosynthesis. Nat Prod Rep 2009; 26:628-60. [PMID: 19387499 DOI: 10.1039/b822528a] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Covering: up to October 2008. Antitumor compounds produced by actinomycetes and novel derivatives generated by combinatorial biosynthesis are reviewed (with 318 references cited.) The different structural groups for which the relevant gene clusters have been isolated and characterized are reviewed, with a description of the strategies used for the generation of the novel derivatives and the activities of these compounds against tumor cell lines.
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Affiliation(s)
- Carlos Olano
- Departamento de Biología Funcional and Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A.), Universidad de Oviedo, 33006, Oviedo, Spain
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32
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Casely-Hayford MA, Nicholas SA, Sumbayev VV. Azinomycin epoxide induces activation of apoptosis signal-regulating kinase 1 (ASK1) and caspase 3 in a HIF-1α-independent manner in human leukaemia myeloid macrophages. Eur J Pharmacol 2009; 602:262-7. [DOI: 10.1016/j.ejphar.2008.12.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2008] [Revised: 11/18/2008] [Accepted: 12/01/2008] [Indexed: 12/01/2022]
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33
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Zhao Q, He Q, Ding W, Tang M, Kang Q, Yu Y, Deng W, Zhang Q, Fang J, Tang G, Liu W. Characterization of the Azinomycin B Biosynthetic Gene Cluster Revealing a Different Iterative Type I Polyketide Synthase for Naphthoate Biosynthesis. ACTA ACUST UNITED AC 2008; 15:693-705. [DOI: 10.1016/j.chembiol.2008.05.021] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2008] [Revised: 05/20/2008] [Accepted: 05/27/2008] [Indexed: 02/07/2023]
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34
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Comba P, Kerscher M, Schiek W. Bispidine Coordination Chemistry. PROGRESS IN INORGANIC CHEMISTRY 2008. [DOI: 10.1002/9780470144428.ch9] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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35
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Kelly GT, Sharma V, Watanabe CMH. An improved method for culturing Streptomyces sahachiroi: Biosynthetic origin of the enol fragment of azinomycin B. Bioorg Chem 2008; 36:4-15. [PMID: 17904193 DOI: 10.1016/j.bioorg.2007.08.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2007] [Accepted: 07/26/2007] [Indexed: 11/16/2022]
Abstract
Azinomycin B is an environmental DNA crosslinking agent produced by the soil microorganism Streptomyces sahachiroi. While the agent displays potent cytotoxic activities against leukemic cell lines and animal mouse models, the lack of a consistent supply of the natural product has hampered detailed biological investigations on the compound, including its mode of action and biosynthesis. We report here a significant methodological improvement in the culturing of the bacterium, which allows reliable and steady production of the natural product in good yields. The key experimental step involves the culturing of the strain on dehydrated plates, followed by the generation of a two-stage starter culture and subsequent fermentation of the strain under nutrient-starved conditions. We illustrate use of this culture system by investigating the formation of the enol fragment of the molecule in isotopic labeling experiments with threonine and several advanced precursors (beta-ketoamino acid 3, beta-hydroxyamino aldehyde 4, and beta-ketoaminoaldehyde 5). The results unequivocally show that threonine is the most advanced precursor accepted by the NRPS (non-ribosomal peptidyl synthetase) machinery for final processing and construction of the enol moiety of the natural product.
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Affiliation(s)
- Gilbert T Kelly
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, TX 77843, USA
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36
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Coleman RS, Tierney MT, Cortright SB, Carper DJ. Synthesis of Functional “Top-Half” Partial Structures of Azinomycin A and B. J Org Chem 2007; 72:7726-35. [PMID: 17824658 DOI: 10.1021/jo7014888] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The design and synthesis of a detailed series of functional "top-half" substructures of azinomycin A and B is described.
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Affiliation(s)
- Robert S Coleman
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA.
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37
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Coleman RS, Woodward RL, Hayes AM, Crane EA, Artese A, Ortuso F, Alcaro S. Dependence of DNA Sequence Selectivity and Cell Cytotoxicity on Azinomycin A and B Epoxyamide Stereochemistry. Org Lett 2007; 9:1891-4. [PMID: 17432865 DOI: 10.1021/ol070395s] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Evaluation of the importance of C18/C19 stereochemistry of azinomycin A/B epoxyamide partial structures with respect to DNA alkylation sequence selectivity is reported using a unique assay with a DNA oligomer containing imbedded normal (5'-GGC-3'/3'-CCG-5') and inverted (5'-CGG-3'/3'-GCC-5') azinomycin consensus cross-linking sequences. Both species were found to have unique selectivity profiles and alkylate DNA in a manner distinct from azinomycin B. Computational docking experiments support altered binding modes for the enantiomers.
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Affiliation(s)
- Robert S Coleman
- Department of Chemistry, The Ohio State University, Columbus, OH 43210, USA.
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David-Cordonnier MH, Casely-Hayford M, Kouach M, Briand G, Patterson LH, Bailly C, Searcey M. Stereoselectivity, Sequence Specificity and Mechanism of Action of the Azinomycin Epoxide. Chembiochem 2006; 7:1658-61. [PMID: 16991169 DOI: 10.1002/cbic.200600244] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kelly GT, Liu C, Smith R, Coleman RS, Watanabe CMH. Cellular effects induced by the antitumor agent azinomycin B. ACTA ACUST UNITED AC 2006; 13:485-92. [PMID: 16720269 DOI: 10.1016/j.chembiol.2006.02.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2005] [Revised: 02/17/2006] [Accepted: 02/21/2006] [Indexed: 12/15/2022]
Abstract
Studies on the mechanism of action of the antitumor agent azinomycin B in vitro suggest that the drug elicits its lethal effects by the formation of interstrand crosslinks within the major groove of DNA. Here, we demonstrate the biological effects of the drug in vivo. Fluorescence imaging revealed localization of azinomycin B in the nuclear region of yeast. Moreover, experiments with oligonucleotide microarrays examined the effects of the drug across the yeast transcriptome. The results demonstrated a robust DNA damage response that supports the proposed role of the drug as a covalent DNA modifying agent. RT-PCR analysis validated the gene changes, and flow cytometry of azinomycin-treated yeast cells demonstrated a phenotypic S phase shift consistent with transcriptional effects.
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Affiliation(s)
- Gilbert T Kelly
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA
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Abstract
[reaction: see text] Azinomycins have potential therapeutic value as antitumor agents; however, their biosynthesis is poorly understood. Here, we provide the first demonstration of a protein cell-free system capable of supporting complete in vitro biosynthesis of the antitumor agent azinomycin B. The cell-free system is utilized to probe the cofactor dependence and substrate requirements of the pathway en route to azinomycin.
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Affiliation(s)
- Chaomin Liu
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA
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41
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Alcaro S, Ortuso F, Coleman RS. Molecular modeling of DNA cross-linking analogues based on the azinomycin scaffold. J Chem Inf Model 2005; 45:602-9. [PMID: 15921450 DOI: 10.1021/ci0496595] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this work, we present molecular modeling studies carried out using six DNA sequences and six azinomycin analogues, including the naturally occurring compound azinomycin B, selected on the basis of known cell cytotoxicity and structural analogies (epoxide and aziridine alkylating moieties). Among several computational methods the Stochastic Dynamics with Energy Minimization (SDEM) approach yielded results superior to the others with the natural compound (r(2) > 0.9) and was adopted for studying other DNA adducts, obtaining good correlation between the average theoretical cross-linking properties and the antitumor activity scale. As a result, some interesting SAR considerations have been highlighted and a cross-linking conformation different from that of the azinomycin was identified in a less potent, simplified analogue.
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Affiliation(s)
- Stefano Alcaro
- Dipartimento di Scienze Farmacobiologiche, Università Magna Graecia di Catanzaro, I-88021 Roccelletta di Borgia, Catanzaro, Italy.
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42
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Casely-Hayford MA, Pors K, Patterson LH, Gerner C, Neidle S, Searcey M. Truncated azinomycin analogues intercalate into DNA. Bioorg Med Chem Lett 2005; 15:653-6. [PMID: 15664831 DOI: 10.1016/j.bmcl.2004.11.037] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2004] [Revised: 11/11/2004] [Accepted: 11/15/2004] [Indexed: 11/20/2022]
Abstract
The design and synthesis of a potentially more therapeutically-viable azinomycin analogue 4 based upon 3 has been completed. It involved coupling of a piperidine mustard to the acid chloride of the azinomycin chromophore. Both the designed azinomycin analogue 4 and the natural product 3 bind to DNA and cause unwinding, supporting an intercalative mode of binding.
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Affiliation(s)
- Maxwell A Casely-Hayford
- Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, University of London, 29-39 Brunswick Square, London WC1N 1AX, UK
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Casely-Hayford MA, Pors K, James CH, Patterson LH, Hartley JA, Searcey M. Design and synthesis of a DNA-crosslinking azinomycin analogue. Org Biomol Chem 2005; 3:3585-9. [PMID: 16172698 DOI: 10.1039/b508908e] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The azinomycins are potent antitumour antibiotics that are able to crosslink DNA, but are relatively unstable and unlikely to progress as therapeutic candidates. A prototype analogue 4 with more clinical potential has been designed and synthesised and incorporates the epoxide function of the azinomycins and a nitrogen mustard. Two further analogues 5 and 6 that can alkylate DNA but cannot crosslink the duplex have also been synthesised. Compound 4 crosslinks DNA efficiently at nM concentrations. Compounds 4-6 were submitted to the NCI 60 cell line screen and have similar antitumour activity, although 4 is slightly less active than the non-crosslinking compounds. These observations will be important in the design of further azinomycin analogues with antitumour activity.
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Affiliation(s)
- Maxwell A Casely-Hayford
- Dept. of Pharmaceutical and Biological Chemistry, School of Pharmacy, University of London, 29-39 Brunswick Square, London, UK WC1N 1AX
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LePla RC, Landreau CAS, Shipman M, Jones GDD. On the origin of the DNA sequence selectivity of the azinomycins. Org Biomol Chem 2005; 3:1174-5. [PMID: 15785803 DOI: 10.1039/b502188j] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Simplified synthetic azinomycins preferentially induce in vitro DNA interstrand cross-links at the same 5'-d(GCC)-3' site as the natural products revealing that non-covalent interactions are relatively unimportant in defining sequence specificity.
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Affiliation(s)
- Rachel C LePla
- Department of Chemistry, University of Warwick, Coventry, UK CV4 7AL
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Chapter 2 Total synthesis of the azinomycin family of antitumor agents. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/s1874-6004(04)80025-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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46
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Comba P, Merz M, Pritzkow H. Catalytic Aziridination of Styrene with Copper Complexes of Substituted 3,7-Diazabicyclo[3.3.1]nonanones. Eur J Inorg Chem 2003. [DOI: 10.1002/ejic.200200618] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Coleman RS, Perez RJ, Burk CH, Navarro A. Studies on the mechanism of action of azinomycin B: definition of regioselectivity and sequence selectivity of DNA cross-link formation and clarification of the role of the naphthoate. J Am Chem Soc 2002; 124:13008-17. [PMID: 12405827 DOI: 10.1021/ja025563k] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Evaluation of the sequence selectivity, noncovalent association, and orientation of the DNA cross-linking agent azinomycin B on its duplex DNA receptor is described. A strong correlation between sequence nucleophilicity and cross-linking yield was observed, and steric effects due to the thymine C5-methyl group were identified. Detailed studies on the role of the azinomycin naphthoate using viscometry, fluorescence contact energy transfer, and DNA unwinding assays point to a nonintercalative binding mode for this group. A kinetic assay for agent regioselectivity was used to determine the orientation of binding and covalent cross-link formation.
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Affiliation(s)
- Robert S Coleman
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210-1185, USA.
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Coleman RS, Burk CH, Navarro A, Brueggemeier RW, Diaz-Cruz ES. Role of the azinomycin naphthoate and central amide in sequence-dependent DNA alkylation and cytotoxicity of epoxide-bearing substructures. Org Lett 2002; 4:3545-8. [PMID: 12323065 DOI: 10.1021/ol0267275] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Studies report a strong correlation between duplex DNA alkylation and in vitro cytotoxicity for a series of azinomycin partial structures 2-6 bearing the biologically relevant epoxide. Compounds lacking the naphthoate ester (e.g., 5 and 6) were poorly reactive toward DNA and were biologically inactive, as were compounds bearing the naphthoate but lacking the terminal carboxamide (e.g., 2). Compounds were evaluated for cytotoxicity against two breast cancer cell lines. [structure: see text]
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Affiliation(s)
- Robert S Coleman
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA.
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Alcaro S, Ortuso F, Coleman RS. DNA cross-linking by azinomycin B: Monte Carlo simulations in the evaluation of sequence selectivity. J Med Chem 2002; 45:861-70. [PMID: 11831897 DOI: 10.1021/jm011040w] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new set of charges specifically developed for biologically relevant N7-alkylated purine adducts have been implemented in the AMBER force field of the MacroModel package and applied to the conformational search of azinomycin B-DNA interactions. To perform a sequence dependent reactivity relationship study, four DNA triplets known to interact differently with the drug, 5'-GCT-3', 5'-GCC-3', 5'-GTC-3', and 5'-GTT-3', have been modeled in B-form and intercalative conformations. Monte Carlo simulations of all possible monoadducts and intercalative complexes have been carried out and analyzed using a filtering criterion that estimates the probability of covalent bond formation and covalent cross-linking. We observed a good correlation between existing experimental data and our computational estimations that validate the approach. The comparison of the conformational properties of the drug-DNA monoadducts and complexes confirms the most probable mechanism of action involving an initial aziridine and subsequent epoxide alkylation. The different hydrogen bond network in the monoadducts and in the intercalative complexes between the drug and the three base-pair receptor is the primary reason for the different cross-linking reactivity. In addition, steric hindrance of the major groove exposed methyl group of central thymine-based triplets plays an important role in the lack of the reactivity of these sequences. Synthetic work on the azinomycins and the information coming from this computational study will be important for the design of more potent or DNA sequence-selective agents based on the azinomycin skeleton.
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Affiliation(s)
- Stefano Alcaro
- Dipartimento di Scienze Farmaco-Biologiche, Università di Catanzaro Magna Graecia, 88021 Roccelletta di Borgia, Catanzaro, Italy.
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Affiliation(s)
- Robert S. Coleman
- Department of Chemistry The Ohio State University 100 West 18th Avenue, Columbus, OH 43210‐1185, USA, Fax: (+1) 614‐292‐4647
| | - Jing Li
- Department of Chemistry The Ohio State University 100 West 18th Avenue, Columbus, OH 43210‐1185, USA, Fax: (+1) 614‐292‐4647
| | - Antonio Navarro
- Department of Chemistry The Ohio State University 100 West 18th Avenue, Columbus, OH 43210‐1185, USA, Fax: (+1) 614‐292‐4647
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