1
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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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2
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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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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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Mullowney MW, McClure RA, Robey MT, Kelleher NL, Thomson RJ. Natural products from thioester reductase containing biosynthetic pathways. Nat Prod Rep 2018; 35:847-878. [PMID: 29916519 PMCID: PMC6146020 DOI: 10.1039/c8np00013a] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Covering: up to 2018 Thioester reductase domains catalyze two- and four-electron reductions to release natural products following assembly on nonribosomal peptide synthetases, polyketide synthases, and their hybrid biosynthetic complexes. This reductive off-loading of a natural product yields an aldehyde or alcohol, can initiate the formation of a macrocyclic imine, and contributes to important intermediates in a variety of biosyntheses, including those for polyketide alkaloids and pyrrolobenzodiazepines. Compounds that arise from reductase-terminated biosynthetic gene clusters are often reactive and exhibit biological activity. Biomedically important examples include the cancer therapeutic Yondelis (ecteinascidin 743), peptide aldehydes that inspired the first therapeutic proteasome inhibitor bortezomib, and numerous synthetic derivatives and antibody drug conjugates of the pyrrolobenzodiazepines. Recent advances in microbial genomics, metabolomics, bioinformatics, and reactivity-based labeling have facilitated the detection of these compounds for targeted isolation. Herein, we summarize known natural products arising from this important category, highlighting their occurrence in Nature, biosyntheses, biological activities, and the technologies used for their detection and identification. Additionally, we review publicly available genomic data to highlight the remaining potential for novel reductively tailored compounds and drug leads from microorganisms. This thorough retrospective highlights various molecular families with especially privileged bioactivity while illuminating challenges and prospects toward accelerating the discovery of new, high value natural products.
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Affiliation(s)
- Michael W Mullowney
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA.
| | - Ryan A McClure
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA.
| | - Matthew T Robey
- Department of Molecular Biosciences, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA
| | - Neil L Kelleher
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA. and Department of Molecular Biosciences, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA
| | - Regan J Thomson
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA.
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5
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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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6
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Li W, Zhang J. Recent developments in the synthesis and utilization of chiral β-aminophosphine derivatives as catalysts or ligands. Chem Soc Rev 2016; 45:1657-77. [DOI: 10.1039/c5cs00469a] [Citation(s) in RCA: 185] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In the last few years, the research area of chiral β-aminophosphines capable of promoting a wide range of diverse organic transformations has attracted more attention.
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Affiliation(s)
- Wenbo Li
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- Department of Chemsitry
- East China Normal University
- Shanghai 200062
- China
| | - Junliang Zhang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- Department of Chemsitry
- East China Normal University
- Shanghai 200062
- China
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7
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Albler C, Schmid W. Synthetic Routes towards Fluorine-Containing Amino Sugars: Synthesis of Fluorinated Analogues of Tomosamine and 4-Amino-4-deoxyarabinose. European J Org Chem 2014. [DOI: 10.1002/ejoc.201301614] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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8
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Simkhada D, Zhang H, Mori S, Williams H, Watanabe CMH. Activation of cryptic metabolite production through gene disruption: Dimethyl furan-2,4-dicarboxylate produced by Streptomyces sahachiroi. Beilstein J Org Chem 2013; 9:1768-73. [PMID: 24062841 PMCID: PMC3778384 DOI: 10.3762/bjoc.9.205] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Accepted: 08/09/2013] [Indexed: 01/23/2023] Open
Abstract
At least 65% of all small molecule drugs on the market today are natural products, however, re-isolation of previously identified and characterized compounds has become a serious impediment to the discovery of new bioactive natural products. Here, genetic knockout of an unusual non-ribosomal peptide synthetase (NRPS) C-PCP-C module, aziA2, is performed resulting in the accumulation of the secondary metabolite, dimethyl furan-2,4-dicarboxylate. The cryptic metabolite represents the first non-azinomycin related compound to be isolated and characterized from the soil bacterium, S. sahachiroi. The results from this study suggest that abolishing production of otherwise predominant natural products through genetic knockout may constitute a means to “activate” the production of novel secondary metabolites that would otherwise lay dormant within microbial genome sequences.
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Affiliation(s)
- Dinesh Simkhada
- Texas A&M University, Department of Chemistry, College Station, TX 77843, USA
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9
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Gram scale de novo synthesis of 2,4-diacetamido-2,4,6-trideoxy-d-galactose. Carbohydr Res 2013; 367:1-4. [DOI: 10.1016/j.carres.2012.11.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Revised: 11/20/2012] [Accepted: 11/21/2012] [Indexed: 12/16/2022]
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10
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Wang S, Zhao R, Liu K, Zhu M, Li A, He J. Essential role of an unknown gene aziU3 in the production of antitumor antibiotic azinomycin B verified by utilizing optimized genetic manipulation systems for Streptomyces sahachiroi. FEMS Microbiol Lett 2012; 337:147-54. [PMID: 23039858 DOI: 10.1111/1574-6968.12020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 09/21/2012] [Accepted: 10/02/2012] [Indexed: 11/30/2022] Open
Abstract
Streptomyces sahachiroi ATCC 33158 produces the potent antitumor antibiotic azinomycin B, which is featured with a set of unusual functionalized moieties. However, the genetic analyses of azinomycin B biosynthetic pathway are hampered by the low efficiency of S. sahachiroi genetic manipulation. In this study, we developed two efficient DNA transfer systems for S. sahachiroi ATCC 33158 by optimizing a variety of parameters known to affect intergeneric conjugation and protoplast transformation. High efficiencies of 4 × 10(2) transformants per μg DNA and 2.47 × 10(-4) conjugants per recipient were achieved when using the integrative vector pJTU2554. With the use of these improved genetic manipulation systems, aziU3 was discovered to play a key role in the biosynthesis of azinomycin B. In-frame deletion and complementation experiments demonstrated clearly that aziU3 is essential for azinomycin B biosynthesis. Changing the native promoter and insertion of an additional aziU3 gene copy resulted in two mutant strains over-producing azinomycin B. Real-time PCR verified that overexpression of aziU3 significantly improved the azinomycin B production in these mutant strains.
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Affiliation(s)
- Shan Wang
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
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11
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Hamed RB, Henry L, Gomez-Castellanos JR, Mecinović J, Ducho C, Sorensen JL, Claridge TDW, Schofield CJ. Crotonase Catalysis Enables Flexible Production of Functionalized Prolines and Carbapenams. J Am Chem Soc 2011; 134:471-9. [DOI: 10.1021/ja208318d] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Refaat B. Hamed
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
- Department of Pharmacognosy, Faculty of Pharmacy, Assiut University, Assiut 71526, Egypt
| | - Luc Henry
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | | | - Jasmin Mecinović
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Christian Ducho
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - John L. Sorensen
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Timothy D. W. Claridge
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Christopher J. Schofield
- Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
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12
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Duschek A, Kirsch SF. 2-Iodoxybenzoic Acid-A Simple Oxidant with a Dazzling Array of Potential Applications. Angew Chem Int Ed Engl 2011; 50:1524-52. [DOI: 10.1002/anie.201000873] [Citation(s) in RCA: 205] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Indexed: 12/26/2022]
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13
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Duschek A, Kirsch SF. 2-Iodoxybenzoesäure - ein einfaches Oxidationsmittel mit einer Vielfalt an Anwendungsmöglichkeiten. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201000873] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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14
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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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15
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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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16
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Han X, Wang Y, Zhong F, Lu Y. Enantioselective Morita–Baylis–Hillman reaction promoted by l-threonine-derived phosphine–thiourea catalysts. Org Biomol Chem 2011; 9:6734-40. [DOI: 10.1039/c1ob05881a] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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Tomabechi Y, Odate Y, Izumi R, Haneda K, Inazu T. Acceptor specificity in the transglycosylation reaction using Endo-M. Carbohydr Res 2010; 345:2458-63. [DOI: 10.1016/j.carres.2010.08.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2010] [Revised: 08/21/2010] [Accepted: 08/26/2010] [Indexed: 10/19/2022]
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18
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Zhao K, Penttinen P, Guan T, Xiao J, Chen Q, Xu J, Lindström K, Zhang L, Zhang X, Strobel GA. The Diversity and Anti-Microbial Activity of Endophytic Actinomycetes Isolated from Medicinal Plants in Panxi Plateau, China. Curr Microbiol 2010; 62:182-90. [DOI: 10.1007/s00284-010-9685-3] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2010] [Accepted: 05/20/2010] [Indexed: 10/19/2022]
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19
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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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20
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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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21
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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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22
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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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