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Shaabani A, Farhid H, Rostami MM, Notash B. Synthesis of Depsipeptides via Isocyanide-Based Consecutive Bargellini–Passerini Multicomponent Reactions. SYNOPEN 2021. [DOI: 10.1055/a-1533-3823] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
AbstractAn efficient and straightforward approach has been established for the preparation of a new class of depsipeptide structures via isocyanide-based consecutive Bargellini–Passerini multicomponent reactions. 3-Carboxamido-isobutyric acids bearing an amide bond were obtained via Bargellini multicomponent reaction from isocyanides, acetone, and chloroform in the presence of sodium hydroxide. Next, via a Passerini multicomponent-reaction strategy, a new class of depsipeptides was synthesized using the Bargellini reaction products, isocyanides, and aldehydes. The depsipeptides thus prepared have more flexible structures than their pseudopeptidic analogues.
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Affiliation(s)
- Ahmad Shaabani
- Faculty of Chemistry, Shahid Beheshti University
- Рeoples’ Friendship University of Russia (RUDN University)
| | | | | | - Behrouz Notash
- Department of Inorganic Chemistry and Catalysis, Shahid Beheshti University
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2
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Kumar B, Maity J, Shankar B, Kumar S, Kavita, Prasad AK. Synthesis of d-glycopyranosyl depsipeptides using Passerini reaction. Carbohydr Res 2021; 500:108236. [PMID: 33516073 DOI: 10.1016/j.carres.2021.108236] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 12/31/2020] [Accepted: 01/04/2021] [Indexed: 11/16/2022]
Abstract
A protocol based on Passerini multi-component reaction has been developed for facile, efficient and atom economical synthesis of a small library of twenty potential bioactive (2R)-2-(d-glycopyranosyl)-2-acyloxyacetamides using perbenzylated d-glycopyranosyl aldehydes, substituted isocyanides and different aliphatic/aromatic carboxylic acids. All twenty synthesized d-glycopyranosyl α-acyloxy amides, commonly known as depsipeptides were unambiguously identified on the basis of their spectral (IR, 1H, 13C NMR, COSY, HSQC, NOESY and HRMS) data analysis.
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Affiliation(s)
- Banty Kumar
- Bioorganic Laboratory, Department of Chemistry, University of Delhi, Delhi, 110007, India; Department of Chemistry, Rajdhani College, University of Delhi, Delhi, 110015, India
| | - Jyotirmoy Maity
- Department of Chemistry, St. Stephen's College, University of Delhi, Delhi, 110007, India
| | - Bhawani Shankar
- Bioorganic Laboratory, Department of Chemistry, University of Delhi, Delhi, 110007, India; Department of Chemistry, Deshbandhu College, University of Delhi, Delhi, 110019, India
| | - Sandeep Kumar
- Bioorganic Laboratory, Department of Chemistry, University of Delhi, Delhi, 110007, India
| | - Kavita
- Bioorganic Laboratory, Department of Chemistry, University of Delhi, Delhi, 110007, India
| | - Ashok K Prasad
- Bioorganic Laboratory, Department of Chemistry, University of Delhi, Delhi, 110007, India.
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3
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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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4
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Ficellomycin: an aziridine alkaloid antibiotic with potential therapeutic capacity. Appl Microbiol Biotechnol 2018; 102:4345-4354. [DOI: 10.1007/s00253-018-8934-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 03/09/2018] [Accepted: 03/13/2018] [Indexed: 10/17/2022]
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5
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Identification and characterization of the ficellomycin biosynthesis gene cluster from Streptomyces ficellus. Appl Microbiol Biotechnol 2017; 101:7589-7602. [DOI: 10.1007/s00253-017-8465-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 08/02/2017] [Accepted: 08/03/2017] [Indexed: 02/03/2023]
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6
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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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7
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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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Morgado G, Gerngross D, Roberts TM, Panke S. Synthetic Biology for Cell-Free Biosynthesis: Fundamentals of Designing Novel In Vitro Multi-Enzyme Reaction Networks. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2016; 162:117-146. [PMID: 27757475 DOI: 10.1007/10_2016_13] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cell-free biosynthesis in the form of in vitro multi-enzyme reaction networks or enzyme cascade reactions emerges as a promising tool to carry out complex catalysis in one-step, one-vessel settings. It combines the advantages of well-established in vitro biocatalysis with the power of multi-step in vivo pathways. Such cascades have been successfully applied to the synthesis of fine and bulk chemicals, monomers and complex polymers of chemical importance, and energy molecules from renewable resources as well as electricity. The scale of these initial attempts remains small, suggesting that more robust control of such systems and more efficient optimization are currently major bottlenecks. To this end, the very nature of enzyme cascade reactions as multi-membered systems requires novel approaches for implementation and optimization, some of which can be obtained from in vivo disciplines (such as pathway refactoring and DNA assembly), and some of which can be built on the unique, cell-free properties of cascade reactions (such as easy analytical access to all system intermediates to facilitate modeling).
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Affiliation(s)
- Gaspar Morgado
- Bioprocess Laboratory, Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, 4058, Basel, Switzerland
| | - Daniel Gerngross
- Bioprocess Laboratory, Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, 4058, Basel, Switzerland
| | - Tania M Roberts
- Bioprocess Laboratory, Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, 4058, Basel, Switzerland
| | - Sven Panke
- Bioprocess Laboratory, Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, 4058, Basel, Switzerland.
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Dudley QM, Karim AS, Jewett MC. Cell-free metabolic engineering: biomanufacturing beyond the cell. Biotechnol J 2015; 10:69-82. [PMID: 25319678 PMCID: PMC4314355 DOI: 10.1002/biot.201400330] [Citation(s) in RCA: 214] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 07/24/2014] [Accepted: 08/22/2014] [Indexed: 12/20/2022]
Abstract
Industrial biotechnology and microbial metabolic engineering are poised to help meet the growing demand for sustainable, low-cost commodity chemicals and natural products, yet the fraction of biochemicals amenable to commercial production remains limited. Common problems afflicting the current state-of-the-art include low volumetric productivities, build-up of toxic intermediates or products, and byproduct losses via competing pathways. To overcome these limitations, cell-free metabolic engineering (CFME) is expanding the scope of the traditional bioengineering model by using in vitro ensembles of catalytic proteins prepared from purified enzymes or crude lysates of cells for the production of target products. In recent years, the unprecedented level of control and freedom of design, relative to in vivo systems, has inspired the development of engineering foundations for cell-free systems. These efforts have led to activation of long enzymatic pathways (>8 enzymes), near theoretical conversion yields, productivities greater than 100 mg L(-1) h(-1) , reaction scales of >100 L, and new directions in protein purification, spatial organization, and enzyme stability. In the coming years, CFME will offer exciting opportunities to: (i) debug and optimize biosynthetic pathways; (ii) carry out design-build-test iterations without re-engineering organisms; and (iii) perform molecular transformations when bioconversion yields, productivities, or cellular toxicity limit commercial feasibility.
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Affiliation(s)
| | | | - Michael C. Jewett
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL, USA
- Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, USA
- Member, Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, IL, USA
- Member, Institute for Bionanotechnology in Medicine, Northwestern University, Chicago, IL, USA
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10
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Thibodeaux CJ, Chang WC, Liu HW. Enzymatic chemistry of cyclopropane, epoxide, and aziridine biosynthesis. Chem Rev 2012; 112:1681-709. [PMID: 22017381 PMCID: PMC3288687 DOI: 10.1021/cr200073d] [Citation(s) in RCA: 204] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Wei-chen Chang
- College of Pharmacy and Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712
| | - Hung-wen Liu
- Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, Texas 78712
- College of Pharmacy and Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712
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Wu J, Zhao W, Cao S. Synthesis of Difluoromethyl-Containing α-Acyloxycarboxamide Derivatives through a Passerini Reaction and Desulfonylation. European J Org Chem 2012. [DOI: 10.1002/ejoc.201101518] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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12
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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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13
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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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14
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Ogasawara Y, Liu HW. Biosynthetic studies of aziridine formation in azicemicins. J Am Chem Soc 2010; 131:18066-8. [PMID: 19928906 DOI: 10.1021/ja907307h] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The azicemicins, which are angucycline-type antibiotics produced by the actinomycete, Kibdelosporangium sp. MJ126-NF4, contain an aziridine ring attached to the polyketide core. Feeding experiments using [1-(13)C]acetate or [1,2-(13)C(2)]acetate indicated that the angucycline skeleton is biosynthesized by a type II polyketide synthase. Isotope-tracer experiments using deuterium-labeled amino acids revealed that aspartic acid is the precursor of the aziridine moiety. Subsequent cloning and sequencing efforts led to the identification of the azicemicin (azic) gene cluster spanning approximately 50 kbp. The cluster harbors genes typical for type II polyketide synthesis. Also contained in the cluster are genes for two adenylyl transferases, a decarboxylase, an additional acyl carrier protein (ACP), and several oxygenases. On the basis of the assigned functions of these genes, a possible pathway for aziridine ring formation in the azecimicins can now be proposed. To obtain support for the proposed biosynthetic pathway, two genes encoding adenylyltransferases were overexpressed and the resulting proteins were purified. Enzyme assays showed that one of the adenylyltransferases specifically recognizes aspartic acid, providing strong evidence, in addition to the feeding experiments, that aspartate is the precursor of the aziridine moiety. The results reported herein set the stage for future biochemical studies of aziridine biosynthesis and assembly.
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Affiliation(s)
- Yasushi Ogasawara
- Division of Medicinal Chemistry, College of Pharmacy, and Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712, USA
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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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Sharma V, Kelly GT, Foulke-Abel J, Watanabe CMH. Aminoacetone as the Penultimate Precursor to the Antitumor Agent Azinomycin A. Org Lett 2009; 11:4006-9. [DOI: 10.1021/ol9016639] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Vasudha Sharma
- Department of Chemistry, Texas A&M University, College Station, Texas 77843
| | - Gilbert T. Kelly
- Department of Chemistry, Texas A&M University, College Station, Texas 77843
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Sharma V, Kelly GT, Watanabe CMH. Exploration of the Molecular Origin of the Azinomycin Epoxide: Timing of the Biosynthesis Revealed. Org Lett 2008; 10:4815-8. [DOI: 10.1021/ol8018852] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Vasudha Sharma
- Department of Chemistry, Texas A&M University, College Station, Texas 77842
| | - Gilbert T. Kelly
- Department of Chemistry, Texas A&M University, College Station, Texas 77842
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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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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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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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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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