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Li ZR, Li R, Pasternack L, Chen P, Wong CH. Chemical Synthesis of a Keto Sugar Nucleotide. J Org Chem 2023. [PMID: 37126664 DOI: 10.1021/acs.joc.3c00553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Keto sugar nucleotides (KSNs) are common and versatile precursors to various deoxy sugar nucleotides, which are substrates for the corresponding glycosyltransferases involved in the biosynthesis of glycoproteins, glycolipids, and natural products. However, there has been no KSN synthesized chemically due to the inherent instability. Herein, the first chemical synthesis of the archetypal KSN TDP-4-keto-6-deoxy-d-glucose (1) is achieved by an efficient and optimized route, providing feasible access to other KSNs and analogues, thereby opening a new avenue for new applications.
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Affiliation(s)
- Zhong-Rui Li
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Ruofan Li
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Laura Pasternack
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Pengxi Chen
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Chi-Huey Wong
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, United States
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2
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New Sipanmycin Analogues Generated by Combinatorial Biosynthesis and Mutasynthesis Approaches Relying on the Substrate Flexibility of Key Enzymes in the Biosynthetic Pathway. Appl Environ Microbiol 2020; 86:AEM.02453-19. [PMID: 31732573 DOI: 10.1128/aem.02453-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 11/08/2019] [Indexed: 12/12/2022] Open
Abstract
The appearance of new infectious diseases, the increase in multidrug-resistant bacteria, and the need for more effective chemotherapeutic agents have oriented the interests of researchers toward the search for metabolites with novel or improved bioactivities. Sipanmycins are disaccharyl glycosylated macrolactams that exert antibiotic and cytotoxic activities. By applying combinatorial biosynthesis and mutasynthesis approaches, we have generated eight new members of the sipanmycin family. The introduction of plasmids harboring genes responsible for the biosynthesis of several deoxysugars into sipanmycin-producing Streptomyces sp. strain CS149 led to the production of six derivatives with altered glycosylation patterns. After structural elucidation of these new metabolites, we conclude that some of these sugars are the result of the combination of the enzymatic machinery encoded by the introduced plasmids and the native enzymes of the d-sipanose biosynthetic pathway of the wild-type CS149 strain. In addition, two analogues of the parental compounds with a modified polyketide backbone were generated by a mutasynthesis approach, feeding cultures of a mutant strain defective in sipanmycin biosynthesis with 3-aminopentanoic acid. The generation of new sipanmycin analogues shown in this work relied on the substrate flexibility of key enzymes involved in sipanmycin biosynthesis, particularly the glycosyltransferase pair SipS9/SipS14 and enzymes SipL3, SipL1, SipL7, and SipL2, which are involved in the incorporation of the polyketide synthase starting unit.IMPORTANCE Combinatorial biosynthesis has proved its usefulness in generating derivatives of already known compounds with novel or improved pharmacological properties. Sipanmycins are a family of glycosylated macrolactams produced by Streptomyces sp. strain CS149, whose antiproliferative activity is dependent on the sugar moieties attached to the aglycone. In this work, we report the generation of several sipanmycin analogues with different deoxysugars, showing the high degree of flexibility exerted by the glycosyltransferase machinery with respect to the recognition of diverse nucleotide-activated sugars. In addition, modifications in the macrolactam ring were introduced by mutasynthesis approaches, indicating that the enzymes involved in incorporating the starter unit have a moderate ability to introduce different types of β-amino acids. In conclusion, we have proved the substrate flexibility of key enzymes involved in sipanmycin biosynthesis, especially the glycosyltransferases, which can be exploited in future experiments.
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3
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Forget SM, Shepard SB, Soleimani E, Jakeman DL. On the Catalytic Activity of a GT1 Family Glycosyltransferase from Streptomyces venezuelae ISP5230. J Org Chem 2019; 84:11482-11492. [PMID: 31429289 DOI: 10.1021/acs.joc.9b01130] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
GT1 family glycosyltansferase, Sv0189, from Streptomyces venezuelae ISP5230 (ATCC 10721) was characterized. The recombinantly produced protein Sv0189 possessed UDP-glycosyltransferase activity. Screening, using an assay employing unnatural nitrophenyl glycosides as activated donors, resulted in the discovery of a broad substrate scope with respect to both acceptor molecules and donor sugars. In addition to polyphenols, including anthraquinones, simple aromatics containing primary or secondary alcohols, a variety of complex natural products and synthetic drugs were glucosylated or xylosylated by Sv0189. Regioselectivity was established through the isolation and characterization of glucosylated products. Sv0189 and homologous proteins are widely distributed among Streptomyces species, and their apparent substrate promiscuity reveals potential for their development as biocatalysts for glycodiversification.
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Affiliation(s)
| | | | - Ebrahim Soleimani
- Department of Chemistry , Razi University , Kermanshah 67149-67346 , Iran
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4
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Yanagi M, Ueda Y, Ninomiya R, Imayoshi A, Furuta T, Mishiro K, Kawabata T. Synthesis of 4-Deoxy Pyranosides via Catalyst-Controlled Site-Selective Toluoylation of Abundant Sugars. Org Lett 2019; 21:5006-5009. [DOI: 10.1021/acs.orglett.9b01549] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Masanori Yanagi
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Yoshihiro Ueda
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Ryo Ninomiya
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Ayumi Imayoshi
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Takumi Furuta
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Kenji Mishiro
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Takeo Kawabata
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
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5
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Abstract
The jadomycin family of natural products was discovered from Streptomyces venezuelae ISP5230 in the 1990s. Subsequent identification of the biosynthetic gene cluster along with synthetic efforts established that incorporation of an amino acid into the polyaromatic angucycline core occurs non-enzymatically. Over two decades, the precursor-directed biosynthetic potential of the jadomycins has been heavily exploited, generating a library exceeding 70 compounds. This review compiles the jadomycins that have been isolated and characterized to date; these include jadomycins incorporating proteinogenic and non-proteinogenic amino acids, semi-synthetic derivatives, biosynthetic shunt products, compounds isolated in structural gene deletion studies, and deoxysugar sugar variant jadomycins produced by deletion or heterologous expression of sugar biosynthetic genes.
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Affiliation(s)
- Jeanna M. MacLeod
- College of Pharmacy, Dalhousie University, Halifax, NS, B3H 1X7, Canada
| | | | - David L. Jakeman
- College of Pharmacy, Dalhousie University, Halifax, NS, B3H 1X7, Canada
- Department of Chemistry, Dalhousie University, Halifax, NS, B3H 4R2, Canada
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6
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Malmierca MG, González-Montes L, Pérez-Victoria I, Sialer C, Braña AF, García Salcedo R, Martín J, Reyes F, Méndez C, Olano C, Salas JA. Searching for Glycosylated Natural Products in Actinomycetes and Identification of Novel Macrolactams and Angucyclines. Front Microbiol 2018; 9:39. [PMID: 29441046 PMCID: PMC5797532 DOI: 10.3389/fmicb.2018.00039] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 01/09/2018] [Indexed: 11/13/2022] Open
Abstract
Many bioactive natural products are glycosylated compounds in which the sugar components usually participate in interaction and molecular recognition of the cellular target. Therefore, the presence of sugar moieties is important, in some cases essential, for bioactivity. Searching for novel glycosylated bioactive compounds is an important aim in the field of the research for natural products from actinomycetes. A great majority of these sugar moieties belong to the 6-deoxyhexoses and share two common biosynthetic steps catalyzed by a NDP-D-glucose synthase (GS) and a NDP-D-glucose 4,6-dehydratase (DH). Based on this fact, seventy one Streptomyces strains isolated from the integument of ants of the Tribe Attini were screened for the presence of biosynthetic gene clusters (BGCs) for glycosylated compounds. Total DNAs were analyzed by PCR amplification using oligo primers for GSs and DHs and also for a NDP-D-glucose-2,3-dehydratases. Amplicons were used in gene disruption experiments to generate non-producing mutants in the corresponding clusters. Eleven mutants were obtained and comparative dereplication analyses between the wild type strains and the corresponding mutants allowed in some cases the identification of the compound coded by the corresponding cluster (lobophorins, vicenistatin, chromomycins and benzanthrins) and that of two novel macrolactams (sipanmycin A and B). Several strains did not show UPLC differential peaks between the wild type strain and mutant profiles. However, after genome sequencing of these strains, the activation of the expression of two clusters was achieved by using nutritional and genetic approaches leading to the identification of compounds of the cervimycins family and two novel members of the warkmycins family. Our work defines a useful strategy for the identification new glycosylated compounds by a combination of genome mining, gene inactivation experiments and the activation of silent biosynthetic clusters in Streptomyces strains.
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Affiliation(s)
- Mónica G Malmierca
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain.,Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain
| | - Lorena González-Montes
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain
| | | | - Carlos Sialer
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain
| | - Alfredo F Braña
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain.,Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain
| | - Raúl García Salcedo
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain
| | - Jesús Martín
- Fundación MEDINA, Parque Tecnológico de Ciencias de la Salud, Granada, Spain
| | - Fernando Reyes
- Fundación MEDINA, Parque Tecnológico de Ciencias de la Salud, Granada, Spain
| | - Carmen Méndez
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain.,Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain
| | - Carlos Olano
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain.,Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain
| | - José A Salas
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain.,Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain
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Salcedo RG, Olano C, Fernández R, Braña AF, Méndez C, de la Calle F, Salas JA. Elucidation of the glycosylation steps during biosynthesis of antitumor macrolides PM100117 and PM100118 and engineering for novel derivatives. Microb Cell Fact 2016; 15:187. [PMID: 27829451 PMCID: PMC5103430 DOI: 10.1186/s12934-016-0591-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Accepted: 11/03/2016] [Indexed: 03/14/2023] Open
Abstract
BACKGROUND Antitumor compounds PM100117 and PM100118 are glycosylated polyketides derived from the marine actinobacteria Streptomyces caniferus GUA-06-05-006A. The organization and characterization of the PM100117/18 biosynthesis gene cluster has been recently reported. RESULTS Based on the preceding information and new genetic engineering data, we have outlined the pathway by which PM100117/18 are glycosylated. Furthermore, these genetic engineering experiments have allowed the generation of novel PM100117/18 analogues. Deletion of putative glycosyltranferase genes and additional genes presumably involved in late biosynthesis steps of the three 2,6-dideoxysugars appended to the PM100117/18 polyketide skeleton, resulted in the generation of a series of intermediates and novel derivatives. CONCLUSIONS Isolation and identification of the novel compounds constitutes an important contribution to our knowledge on PM100117/18 glycosylation, and set the basis for further characterization of specific enzymatic reactions, additional genetic engineering and combinatorial biosynthesis approaches.
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Affiliation(s)
- Raúl García Salcedo
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, Asturias, 33006, Oviedo, Spain
| | - Carlos Olano
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, Asturias, 33006, Oviedo, Spain
| | - Rogelio Fernández
- Drug Discovery Area, PharmaMar S.A., Avda. de los Reyes, Colmenar Viejo, 128770, Madrid, Spain
| | - Alfredo F Braña
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, Asturias, 33006, Oviedo, Spain
| | - Carmen Méndez
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, Asturias, 33006, Oviedo, Spain
| | - Fernando de la Calle
- Drug Discovery Area, PharmaMar S.A., Avda. de los Reyes, Colmenar Viejo, 128770, Madrid, Spain
| | - José A Salas
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, Asturias, 33006, Oviedo, Spain.
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8
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Bekeova C, Rehakova A, Feckova L, Vlckova S, Novakova R, Mingyar E, Kormanec J. Characterisation of the genes involved in the biosynthesis and attachment of the aminodeoxysugar D-forosamine in the auricin gene cluster of Streptomyces aureofaciens CCM3239. Appl Microbiol Biotechnol 2015; 100:3177-95. [PMID: 26685675 DOI: 10.1007/s00253-015-7214-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Revised: 11/27/2015] [Accepted: 12/02/2015] [Indexed: 11/27/2022]
Abstract
We previously identified the aur1 gene cluster which produces the angucycline antibiotic auricin. Preliminary characterisation of auricin revealed that it is modified by a single aminodeoxysugar, D-forosamine. Here we characterise the D-forosamine-specific genes. The four close tandem genes, aur1TQSV, encoding enzymes involved in the initial steps of the deoxysugar biosynthesis, were located on a large operon with other core auricin biosynthetic genes. Deleting these genes resulted in the absence of auricin and the production of deglycosylated auricin intermediates. The two final D-forosamine biosynthetic genes, sa59, an NDP-hexose aminotransferase, and sa52, an NDP-aminohexose N-dimethyltransferase, are located in a region rather distant from the core auricin genes. A deletion analysis of these genes confirmed their role in D-forosamine biosynthesis. The Δsa59 mutant had a phenotype similar to that of the cluster deletion mutant, while the Δsa52 mutant produced an auricin with a demethylated D-forosamine. Although auricin contains a single deoxyhexose, two glycosyltransferase genes were found to participate in the attachment of D-forosamine to the auricin aglycon. An analysis of the expression of the D-forosamine biosynthesis genes revealed that the initial D-forosamine biosynthetic genes aur1TQSV are regulated together with the other auricin core genes by the aur1Ap promoter under the control of the auricin-specific activator Aur1P. The expression of the other D-forosamine genes, however, is governed by promoters differentially dependent upon the two SARP family auricin-specific activators Aur1PR3 and Aur1PR4. These promoters contain direct repeats similar to the SARP consensus sequence and are involved in the interaction with both regulators.
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Affiliation(s)
- Carmen Bekeova
- Institute of Molecular Biology, Slovak Academy of Sciences, Dubravska cesta 21, 845 51, Bratislava, Slovak Republic
| | - Alena Rehakova
- Institute of Molecular Biology, Slovak Academy of Sciences, Dubravska cesta 21, 845 51, Bratislava, Slovak Republic
| | - Lubomira Feckova
- Institute of Molecular Biology, Slovak Academy of Sciences, Dubravska cesta 21, 845 51, Bratislava, Slovak Republic
| | - Silvia Vlckova
- Institute of Chemistry, Slovak Academy of Sciences, 845 38, Bratislava, Slovak Republic
| | - Renata Novakova
- Institute of Molecular Biology, Slovak Academy of Sciences, Dubravska cesta 21, 845 51, Bratislava, Slovak Republic
| | - Erik Mingyar
- Institute of Molecular Biology, Slovak Academy of Sciences, Dubravska cesta 21, 845 51, Bratislava, Slovak Republic
| | - Jan Kormanec
- Institute of Molecular Biology, Slovak Academy of Sciences, Dubravska cesta 21, 845 51, Bratislava, Slovak Republic.
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De Bruyn F, Maertens J, Beauprez J, Soetaert W, De Mey M. Biotechnological advances in UDP-sugar based glycosylation of small molecules. Biotechnol Adv 2015; 33:288-302. [PMID: 25698505 DOI: 10.1016/j.biotechadv.2015.02.005] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 12/19/2014] [Accepted: 02/09/2015] [Indexed: 01/04/2023]
Abstract
Glycosylation of small molecules like specialized (secondary) metabolites has a profound impact on their solubility, stability or bioactivity, making glycosides attractive compounds as food additives, therapeutics or nutraceuticals. The subsequently growing market demand has fuelled the development of various biotechnological processes, which can be divided in the in vitro (using enzymes) or in vivo (using whole cells) production of glycosides. In this context, uridine glycosyltransferases (UGTs) have emerged as promising catalysts for the regio- and stereoselective glycosylation of various small molecules, hereby using uridine diphosphate (UDP) sugars as activated glycosyldonors. This review gives an extensive overview of the recently developed in vivo production processes using UGTs and discusses the major routes towards UDP-sugar formation. Furthermore, the use of interconverting enzymes and glycorandomization is highlighted for the production of unusual or new-to-nature glycosides. Finally, the technological challenges and future trends in UDP-sugar based glycosylation are critically evaluated and summarized.
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Affiliation(s)
- Frederik De Bruyn
- Centre of Expertise-Industrial Biotechnology and Biocatalysis, Department of Biochemical and Microbial Technology, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Jo Maertens
- Centre of Expertise-Industrial Biotechnology and Biocatalysis, Department of Biochemical and Microbial Technology, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Joeri Beauprez
- Centre of Expertise-Industrial Biotechnology and Biocatalysis, Department of Biochemical and Microbial Technology, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Wim Soetaert
- Centre of Expertise-Industrial Biotechnology and Biocatalysis, Department of Biochemical and Microbial Technology, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Marjan De Mey
- Centre of Expertise-Industrial Biotechnology and Biocatalysis, Department of Biochemical and Microbial Technology, Ghent University, Coupure links 653, 9000 Ghent, Belgium.
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10
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Rebets Y, Tokovenko B, Lushchyk I, Rückert C, Zaburannyi N, Bechthold A, Kalinowski J, Luzhetskyy A. Complete genome sequence of producer of the glycopeptide antibiotic Aculeximycin Kutzneria albida DSM 43870T, a representative of minor genus of Pseudonocardiaceae. BMC Genomics 2014; 15:885. [PMID: 25301375 PMCID: PMC4210621 DOI: 10.1186/1471-2164-15-885] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 10/03/2014] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Kutzneria is a representative of a rarely observed genus of the family Pseudonocardiaceae. Kutzneria species were initially placed in the Streptosporangiaceae genus and later reconsidered to be an independent genus of the Pseudonocardiaceae. Kutzneria albida is one of the eight known members of the genus. This strain is a unique producer of the glycosylated polyole macrolide aculeximycin which is active against both bacteria and fungi. Kutzneria albida genome sequencing and analysis allow a deeper understanding of evolution of this genus of Pseudonocardiaceae, provide new insight in the phylogeny of the genus, as well as decipher the hidden secondary metabolic potential of these rare actinobacteria. RESULTS To explore the biosynthetic potential of Kutzneria albida to its full extent, the complete genome was sequenced. With a size of 9,874,926 bp, coding for 8,822 genes, it stands alongside other Pseudonocardiaceae with large circular genomes. Genome analysis revealed 46 gene clusters potentially encoding secondary metabolite biosynthesis pathways. Two large genomic islands were identified, containing regions most enriched with secondary metabolism gene clusters. Large parts of this secondary metabolism "clustome" are dedicated to siderophores production. CONCLUSIONS Kutzneria albida is the first species of the genus Kutzneria with a completely sequenced genome. Genome sequencing allowed identifying the gene cluster responsible for the biosynthesis of aculeximycin, one of the largest known oligosaccharide-macrolide antibiotics. Moreover, the genome revealed 45 additional putative secondary metabolite gene clusters, suggesting a huge biosynthetic potential, which makes Kutzneria albida a very rich source of natural products. Comparison of the Kutzneria albida genome to genomes of other actinobacteria clearly shows its close relations with Pseudonocardiaceae in line with the taxonomic position of the genus.
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Affiliation(s)
- Yuriy Rebets
- />Helmholtz-Institute for Pharmaceutical Research Saarland, Saarland University Campus, Building C2.3, 66123 Saarbrücken, Germany
| | - Bogdan Tokovenko
- />Helmholtz-Institute for Pharmaceutical Research Saarland, Saarland University Campus, Building C2.3, 66123 Saarbrücken, Germany
| | - Igor Lushchyk
- />Helmholtz-Institute for Pharmaceutical Research Saarland, Saarland University Campus, Building C2.3, 66123 Saarbrücken, Germany
| | - Christian Rückert
- />Center for Biotechnology, Bielefeld University, Universitätsstraße 27, 33615 Bielefeld, Germany
| | - Nestor Zaburannyi
- />Helmholtz-Institute for Pharmaceutical Research Saarland, Saarland University Campus, Building C2.3, 66123 Saarbrücken, Germany
| | - Andreas Bechthold
- />Institut für Pharmazeutische Biologie und Biotechnologie, Albert-Ludwigs Universität, Stefan-Meier-Strasse 19, 79104 Freiburg, Germany
| | - Jörn Kalinowski
- />Center for Biotechnology, Bielefeld University, Universitätsstraße 27, 33615 Bielefeld, Germany
| | - Andriy Luzhetskyy
- />Helmholtz-Institute for Pharmaceutical Research Saarland, Saarland University Campus, Building C2.3, 66123 Saarbrücken, Germany
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11
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Kormanec J, Novakova R, Mingyar E, Feckova L. Intriguing properties of the angucycline antibiotic auricin and complex regulation of its biosynthesis. Appl Microbiol Biotechnol 2013; 98:45-60. [PMID: 24265028 DOI: 10.1007/s00253-013-5373-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Revised: 10/29/2013] [Accepted: 10/30/2013] [Indexed: 11/29/2022]
Abstract
Streptomyces bacteria are major producers of bioactive natural products, including many antibiotics. We identified a gene cluster, aur1, in a large linear plasmid of Streptomyces aureofaciens CCM3239. The cluster is responsible for the production of a new angucycline polyketide antibiotic auricin. Several tailoring biosynthetic genes were scatted in rather distant aur1 flanking regions. Auricin was produced in a very narrow growth phase interval of several hours after entry into stationary phase, after which it was degraded to non-active metabolites because of its instability at the high pH values reached after the production stage. Strict transcriptional regulation of the auricin biosynthetic gene cluster has been demonstrated, including feed-forward and feedback control by auricin intermediates via several of the huge number of regulatory genes present in the aur1 cluster. The complex mechanism may ensure strict confinement of auricin production to a specific growth stage.
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Affiliation(s)
- Jan Kormanec
- Institute of Molecular Biology, Slovak Academy of Sciences, Dubravska cesta 21, 845 51, Bratislava, Slovak Republic,
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12
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Klimishin DA, Rabyk MV, Fedorenko VA. Methylation of nogalose during nogalomycin biosynthesis by Streptomyces nogalater Lv65. Microbiology (Reading) 2013. [DOI: 10.1134/s0026261713010049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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13
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Flores-Ramirez G, Janecek S, Miernyk JA, Skultety L. In silico biosynthesis of virenose, a methylated deoxy-sugar unique to Coxiella burnetii lipopolysaccharide. Proteome Sci 2012; 10:67. [PMID: 23150954 PMCID: PMC3539893 DOI: 10.1186/1477-5956-10-67] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Accepted: 11/05/2012] [Indexed: 12/22/2022] Open
Abstract
UNLABELLED BACKGROUND Coxiella burnetii is Gram-negative bacterium responsible for the zoonosis Q-fever. While it has an obligate intracellular growth habit, it is able to persist for extended periods outside of a host cell and can resist environmental conditions that would be lethal to most prokaryotes. It is these extracellular bacteria that are the infectious stage encountered by eukaryotic hosts. The intracellular form has evolved to grow and replicate within acidified parasitophorous vacuoles. The outer coat of C. burnetii comprises a complex lipopolysaccharide (LPS) component that includes the unique methylated-6-deoxyhexose, virenose. Although potentially important as a biomarker for C. burnetii, the pathway for its biosynthesis remains obscure. RESULTS The 6-deoxyhexoses constitute a large family integral to the LPS of many eubacteria. It is believed that precursors of the methylated-deoxyhexoses traverse common early biosynthetic steps as nucleotide-monosaccharides. As a prelude to a full biosynthetic characterization, we present herein the results from bioinformatics-based, proteomics-supported predictions of the pathway for virenose synthesis. Alternative possibilities are considered which include both GDP-mannose and TDP-glucose as precursors. CONCLUSION We propose that biosynthesis of the unique C. burnetii biomarker, virenose, involves an early pathway similar to that of other C-3'-methylated deoxysugars which then diverges depending upon the nucleotide-carrier involved. The alternatives yield either the D- or L-enantiomers of virenose. Both pathways require five enzymatic steps, beginning with either glucose-6-phosphate or mannose-6-phosphate. Our in silico results comprise a model for virenose biosynthesis that can be directly tested. Definition of this pathway should facilitate the development of therapeutic agents useful for treatment of Q fever, as well as allowing improvements in the methods for diagnosing this highly infectious disease.
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Affiliation(s)
- Gabriela Flores-Ramirez
- Department of Rickettsiology, Institute of Virology, Slovak Academy of Sciences, Dubravska cesta, 9, Bratislava, 845 05, Slovakia
| | - Stefan Janecek
- Laboratory of Protein Evolution, Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, 845 51, Slovakia
| | - Ján A Miernyk
- USDA, Agricultural Research Service, Plant Genetics Research Unit, Columbia, MO, 65211, USA
- Interdisciplinary Plant Group, University of Missouri, Columbia, MO, 65211, USA
- Department of Biochemistry, University of Missouri, Columbia, MO, 65211, USA
| | - Ludovit Skultety
- Department of Rickettsiology, Institute of Virology, Slovak Academy of Sciences, Dubravska cesta, 9, Bratislava, 845 05, Slovakia
- Centre for Molecular Medicine, Slovak Academy of Sciences, Bratislava, 831 01, Slovakia
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Abstract
Mutants of glycosyltransferases and related sugar nucleotide biosynthetic enzymes have been essential for in vitro glycorandomization to create libraries of novel glycosylated natural products and derivatives. These diverse glycorandomized compounds can now be produced in vivo economically by fermenting engineered Escherichia coli cells that express enzyme mutants.
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Affiliation(s)
- Xi Chen
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
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Simkhada D, Lee HC, Sohng JK. Genetic engineering approach for the production of rhamnosyl and allosyl flavonoids from Escherichia coli. Biotechnol Bioeng 2010; 107:154-62. [PMID: 20506539 DOI: 10.1002/bit.22782] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The main functions of glycosylation are stabilization, detoxification and solubilization of substrates and products. To produce glycosylated products, Escherichia coli was engineered by overexpression of TDP-L-rhamnose and TDP-6-deoxy-D-allose biosynthetic gene clusters, and flavonoids were glycosylated by the overexpression of the glycosyltransferase gene from Arabidopsis thaliana. For the glycosylation, these flavonoids (quercetin and kaempferol) were exogenously fed to the host in a biotransformation system. The products were isolated, analyzed and confirmed by HPLC, LC/MS, and ESI-MS/MS analyses. Several conditions (arabinose, IPTG concentration, OD(600), substrate concentration, incubation time) were optimized to increase the production level. We successfully isolated approximately 24 mg/L 3-O-rhamnosyl quercetin and 12.9 mg/L 3-O-rhamnosyl kaempferol upon feeding of 0.2 mM of the respective flavonoids and were also able to isolate 3-O-allosyl quercetin. Thus, this study reveals a method that might be useful for the biosynthesis of rhamnosyl and allosyl flavonoids and for the glycosylation of related compounds.
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Affiliation(s)
- Dinesh Simkhada
- Institute of Biomolecule Reconstruction, Department of Pharmaceutical Engineering, Sun Moon University, Tangjeong-myeon, Asansi, Chungnam, Korea
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Chemoenzymatic and Bioenzymatic Synthesis of Carbohydrate Containing Natural Products. NATURAL PRODUCTS VIA ENZYMATIC REACTIONS 2010; 297:105-48. [DOI: 10.1007/128_2010_78] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Olano C, Méndez C, Salas JA. Post-PKS tailoring steps in natural product-producing actinomycetes from the perspective of combinatorial biosynthesis. Nat Prod Rep 2010; 27:571-616. [DOI: 10.1039/b911956f] [Citation(s) in RCA: 134] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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19
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Combinatorial and Synthetic Biosynthesis in Actinomycetes. FORTSCHRITTE DER CHEMIE ORGANISCHER NATURSTOFFE / PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS, VOL. 93 2010; 93:211-37. [DOI: 10.1007/978-3-7091-0140-7_3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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20
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Olano C, Gómez C, Pérez M, Palomino M, Pineda-Lucena A, Carbajo RJ, Braña AF, Méndez C, Salas JA. Deciphering Biosynthesis of the RNA Polymerase Inhibitor Streptolydigin and Generation of Glycosylated Derivatives. ACTA ACUST UNITED AC 2009; 16:1031-44. [DOI: 10.1016/j.chembiol.2009.09.015] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Revised: 09/15/2009] [Accepted: 09/18/2009] [Indexed: 11/29/2022]
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21
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Singh B, Lee CB, Sohng JK. Precursor for biosynthesis of sugar moiety of doxorubicin depends on rhamnose biosynthetic pathway in Streptomyces peucetius ATCC 27952. Appl Microbiol Biotechnol 2009; 85:1565-74. [PMID: 19777229 DOI: 10.1007/s00253-009-2225-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Revised: 08/19/2009] [Accepted: 08/21/2009] [Indexed: 10/20/2022]
Abstract
The doxorubicin biosynthetic gene cluster in Streptomyces peucetius ATCC 27952 contains a TDP-D-glucose 4,6-dehydratase gene, dnmM, that is putatively involved in the biosynthesis of daunosamine, but the gene contains a frameshift in the DNA sequence that would cause premature termination of translation. In pursuit of another TDP-D-glucose 4,6-dehydratase in S. peucetius, a homologue gene, rmbB, was found, whose deduced product exhibits high sequence similarity to a number of TDP-D-glucose 4,6-dehydratases. The gene was located within a putative rhamnose biosynthetic gene cluster at another locus in the genome. RmbB was verified to be a functional TDP-D-glucose 4,6-dehydratase by enzyme assay as it catalyzed the conversion of TDP-D-glucose into TDP-4-keto-6-deoxy-D-glucose. Inactivation of rmbB in the S. peucetius genome abolished the production of doxorubicin while complementation of the same gene in an rmbB knockout mutant restored the doxorubicin production. Hence, rmbB provides TDP-4-keto-6-deoxy-D-glucose as a nucleotide sugar precursor for the biosynthesis of doxorubicin.
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Affiliation(s)
- Bijay Singh
- Department of Pharmaceutical Engineering, Institute of Biomolecule Reconstruction (iBR), Sun Moon University, Tangjeong-myeon, Asansi, Chungnam 336-708, South Korea
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22
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Abstract
Many bioactive compounds contain as part of their molecules one or more deoxysugar units. Their presence in the final compound is generally necessary for biological activity. These sugars derive from common monosaccharides, like d-glucose, which have lost one or more hydroxyl groups (monodeoxysugars, dideoxysugars, trideoxysugars) during their biosynthesis. These deoxysugars are transferred to the final molecule by the action of a glycosyltransferase. Here, we first summarize the different biosynthetic steps required for the generation of the different families of deoxysugars, including those containing extra methyl or amino groups, or tailoring modifications of the glycosylated compounds. We then give examples of several strategies for modification of the glycosylation pattern of a given bioactive compound: inactivation of genes involved in the biosynthesis of deoxysugars; heterologous expression of genes for the biosynthesis or transfer of a specific deoxysugar; and combinatorial biosynthesis (including the use of gene cassette plasmids). Finally, we report techniques for the isolation and detection of the new glycosylated derivatives generated using these strategies.
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Affiliation(s)
- Felipe Lombó
- Departamento de Biología Funcional and Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, Oviedo, Spain
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Li W, Khullar A, Chou S, Sacramo A, Gerratana B. Biosynthesis of sibiromycin, a potent antitumor antibiotic. Appl Environ Microbiol 2009; 75:2869-78. [PMID: 19270142 PMCID: PMC2681668 DOI: 10.1128/aem.02326-08] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2008] [Accepted: 02/25/2009] [Indexed: 11/20/2022] Open
Abstract
Pyrrolobenzodiazepines, a class of natural products produced by actinomycetes, are sequence selective DNA alkylating compounds with significant antitumor properties. Among the pyrrolo[1,4]benzodiazepines (PBDs) sibiromycin, one of two identified glycosylated PBDs, displays the highest affinity for DNA and the most potent antitumor properties. Despite the promising antitumor properties clinical trials of sibiromycin were precluded by the cardiotoxicity effect in animals attributed to the presence of the C-9 hydroxyl group. As a first step toward the development of sibiromycin analogs, we have cloned and localized the sibiromycin gene cluster to a 32.7-kb contiguous DNA region. Cluster boundaries tentatively assigned by comparative genomics were verified by gene replacement experiments. The sibiromycin gene cluster consisting of 26 open reading frames reveals a "modular" strategy in which the synthesis of the anthranilic and dihydropyrrole moieties is completed before assembly by the nonribosomal peptide synthetase enzymes. In addition, the gene cluster identified includes open reading frames encoding enzymes involved in sibirosamine biosynthesis, as well as regulatory and resistance proteins. Gene replacement and chemical complementation studies are reported to support the proposed biosynthetic pathway.
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Affiliation(s)
- Wei Li
- Department of Chemistry and Biochemistry, Bldg. 091, University of Maryland, College Park, MD 20742, USA
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24
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Zhao P, Ueda JY, Kozone I, Chijiwa S, Takagi M, Kudo F, Nishiyama M, Shin-ya K, Kuzuyama T. New glycosylated derivatives of versipelostatin, the GRP78/Bip molecular chaperone down-regulator, from Streptomyces versipellis 4083-SVS6. Org Biomol Chem 2009; 7:1454-60. [PMID: 19300832 DOI: 10.1039/b817312e] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Four novel glycosylated derivatives of versipelostatin (1), versipelostatins B-E (2-5), were isolated from the culture broth of Streptomyces versipellis 4083-SVS6. The inhibitory activities of the isolated compounds against the expression of molecular chaperone GRP78 induced by 2-deoxyglucose were evaluated. Of the five versipelostatin family members, 1 and 4 were the more potent with IC(50) values of 3.5 and 4.3 microM. These results suggest that the alpha-L-oleandropyranosyl (1-->4)-beta-D-digitoxopyranosyl residue in the sugar moiety may play an important role in down-regulating GRP78 expression induced by 2-deoxyglucose.
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Affiliation(s)
- Ping Zhao
- Laboratory of Cell Biotechnology, Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo113-8657, Japan
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25
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Kren V, Rezanka T. Sweet antibiotics - the role of glycosidic residues in antibiotic and antitumor activity and their randomization. FEMS Microbiol Rev 2008; 32:858-89. [PMID: 18647177 DOI: 10.1111/j.1574-6976.2008.00124.x] [Citation(s) in RCA: 141] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
A large number of antibiotics are glycosides. In numerous cases the glycosidic residues are crucial to their activity; sometimes, glycosylation only improves their pharmacokinetic parameters. Recent developments in molecular glycobiology have improved our understanding of aglycone vs. glycoside activities and made it possible to develop new, more active or more effective glycodrugs based on these findings - a very illustrative recent example is vancomycin. The majority of attention has been devoted to glycosidic antibiotics including their past, present, and probably future position in antimicrobial therapy. The role of the glycosidic residue in the biological activity of glycosidic antibiotics, and the attendant targeting and antibiotic selectivity mediated by glycone and aglycone in antibiotics some antitumor agents is discussed here in detail. Chemical and enzymatic modifications of aglycones in antibiotics, including their synthesis, are demonstrated on various examples, with particular emphasis on the role of specific and mutant glycosyltransferases and glycorandomization in the preparation of these compounds. The last section of this review describes and explains the interactions of the glycone moiety of the antibiotics with DNA and especially the design and structure-activity relationship of glycosidic antibiotics, including their classification based on their aglycone and glycosidic moiety. The new enzymatic methodology 'glycorandomization' enabled the preparation of glycoside libraries and opened up new ways to prepare optimized or entirely novel glycoside antibiotics.
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Affiliation(s)
- Vladimír Kren
- Centre of Biocatalysis and Biotransformation, Institute of Microbiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic.
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26
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Olano C, Lombó F, Méndez C, Salas JA. Improving production of bioactive secondary metabolites in actinomycetes by metabolic engineering. Metab Eng 2008; 10:281-92. [PMID: 18674632 DOI: 10.1016/j.ymben.2008.07.001] [Citation(s) in RCA: 211] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2008] [Revised: 07/08/2008] [Accepted: 07/09/2008] [Indexed: 11/25/2022]
Abstract
Production of secondary metabolites is a process influenced by several physico-chemical factors including nutrient supply, oxygenation, temperature and pH. These factors have been traditionally controlled and optimized in industrial fermentations in order to enhance metabolite production. In addition, traditional mutagenesis programs have been used by the pharmaceutical industry for strain and production yield improvement. In the last years, the development of recombinant DNA technology has provided new tools for approaching yields improvement by means of genetic manipulation of biosynthetic pathways. These efforts are usually focused in redirecting precursor metabolic fluxes, deregulation of biosynthetic pathways and overexpression of specific enzymes involved in metabolic bottlenecks. In addition, efforts have been made for the heterologous expression of biosynthetic gene clusters in other organisms, looking not only for an increase of production levels but also to speed the process by using rapidly growing and easy to manipulate organisms compared to the producing organism. In this review, we will focus on these genetic approaches as applied to bioactive secondary metabolites produced by actinomycetes.
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Affiliation(s)
- Carlos Olano
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, 33006 Oviedo, Spain
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27
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Ramos A, Lombó F, Braña AF, Rohr J, Méndez C, Salas JA. Biosynthesis of elloramycin in Streptomyces olivaceus requires glycosylation by enzymes encoded outside the aglycon cluster. MICROBIOLOGY-SGM 2008; 154:781-788. [PMID: 18310024 DOI: 10.1099/mic.0.2007/014035-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Elloramycin is an anthracycline-like antitumour drug produced by Streptomyces olivaceus Tü2353. Cosmid cos16F4 has been previously shown to direct the biosynthesis of the elloramycin aglycon 8-demethyltetracenomycin C (8-DMTC), but not elloramycin. Sequencing of the 24.2 kb insert in cos16F4 shows the presence of 17 genes involved in elloramycin biosynthesis (elm genes) together with another additional eight ORFs probably not involved in elloramycin biosynthesis. The 17 genes would code for the biosynthesis of the polyketide moiety, sugar transfer, methylation of the tetracyclic ring and the sugar moiety, and export. Four genes (rhaA, rhaB, rhaC and rhaD) encoding the enzymic activities required for the biosynthesis of the sugar l-rhamnose were also identified in the S. olivaceus chromosome. The involvement of this rhamnose gene cluster in elloramycin biosynthesis was demonstrated by insertional inactivation of the rhaB gene, generating a non-producer mutant that accumulates the 8-DMTC C aglycon. Coexpression of cos16F4 with pEM4RO (expressing the four rhamnose biosynthesis genes) in Streptomyces lividans led to the formation of elloramycin, demonstrating that both subclusters are required for elloramycin biosynthesis. These results demonstrate that, in contrast to most of the biosynthesis gene clusters from actinomycetes, genes involved in the biosynthesis of elloramycin are located in two chromosomal loci.
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Affiliation(s)
- Angelina Ramos
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, 33006 Oviedo, Spain
| | - Felipe Lombó
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, 33006 Oviedo, Spain
| | - Alfredo F Braña
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, 33006 Oviedo, Spain
| | - Jürgen Rohr
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 725 Rose Street, Lexington, KY 40536-0082, USA
| | - Carmen Méndez
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, 33006 Oviedo, Spain
| | - José A Salas
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, 33006 Oviedo, Spain
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Hong L, Zhao Z, Melançon CE, Zhang H, Liu HW. In vitro characterization of the enzymes involved in TDP-D-forosamine biosynthesis in the spinosyn pathway of Saccharopolyspora spinosa. J Am Chem Soc 2008; 130:4954-67. [PMID: 18345667 DOI: 10.1021/ja0771383] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Forosamine (4-dimethylamino)-2,3,4,6-tetradeoxy-beta-D-threo-hexopyranose) is a highly deoxygenated sugar component of several important natural products, including the potent yet environmentally benign insecticide spinosyns. To study D-forosamine biosynthesis, the five genes (spnO, N, Q, R, and S) from the spinosyn gene cluster thought to be involved in the conversion of TDP-4-keto-6-deoxy-D-glucose to TDP-D-forosamine were cloned and heterologously expressed, and the corresponding proteins were purified and their activities examined in vitro. Previous work demonstrated that SpnQ functions as a pyridoxamine 5'-monophosphate (PMP)-dependent 3-dehydrase which, in the presence of the cellular reductase pairs ferredoxin/ferredoxin reductase or flavodoxin/flavodoxin reductase, catalyzes C-3 deoxygenation of TDP-4-keto-2,6-dideoxy-D-glucose. It was also established that SpnR functions as a transaminase which converts the SpnQ product, TDP-4-keto-2,3,6-trideoxy-D-glucose, to TDP-4-amino-2,3,4,6-tetradeoxy-D-glucose. The results presented here provide a full account of the characterization of SpnR and SpnQ and reveal that SpnO and SpnN functions as a 2,3-dehydrase and a 3-ketoreductase, respectively. These two enzymes act sequentially to catalyze C-2 deoxygenation of TDP-4-keto-6-deoxy-D-glucose to form the SpnQ substrate, TDP-4-keto-2,6-dideoxy-D-glucose. Evidence has also been obtained to show that SpnS functions as the 4-dimethyltransferase that converts the SpnR product to TDP-D-forosamine. Thus, the biochemical functions of the five enzymes involved in TDP-D-forosamine formation have now been fully elucidated. The steady-state kinetic parameters for the SpnQ-catalyzed reaction have been determined, and the substrate specificities of SpnQ and SpnR have been explored. The implications of this work for natural product glycodiversification and comparative mechanistic analysis of SpnQ and related NDP-sugar 3-dehydrases E1 and ColD are discussed.
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Affiliation(s)
- Lin Hong
- Division of Medicinal Chemistry, College of Pharmacy, University of Texas at Austin, Austin, Texas 78712, USA
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Olano C, Abdelfattah MS, Gullón S, Braña AF, Rohr J, Méndez C, Salas JA. Glycosylated Derivatives of Steffimycin: Insights into the Role of the Sugar Moieties for the Biological Activity. Chembiochem 2008; 9:624-33. [DOI: 10.1002/cbic.200700610] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Baig I, Perez M, Braña AF, Gomathinayagam R, Damodaran C, Salas JA, Méndez C, Rohr J. Mithramycin analogues generated by combinatorial biosynthesis show improved bioactivity. JOURNAL OF NATURAL PRODUCTS 2008; 71:199-207. [PMID: 18197601 PMCID: PMC2442402 DOI: 10.1021/np0705763] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Plasmid pLNBIV was used to overexpress the biosynthetic pathway of nucleoside-diphosphate (NDP)-activated l-digitoxose in the mithramycin producer Streptomyces argillaceus. This led to a "flooding" of the biosynthetic pathway of the antitumor drug mithramycin (MTM) with NDP-activated deoxysugars, which do not normally occur in the pathway, and consequently to the production of the four new mithramycin derivatives 1- 4 with altered saccharide patterns. Their structures reflect that NDP sugars produced by pLNBIV, namely, l-digitoxose and its biosynthetic intermediates, influenced the glycosyl transfer to positions B, D, and E, while positions A and C remained unaffected. All four new structures have unique, previously not found sugar decoration patterns, which arise from either overcoming the substrate specificity or inhibition of certain glycosyltransferases (GTs) of the MTM pathway with the foreign NDP sugars expressed by pLNBIV. An apoptosis TUNEL (=terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) assay revealed that compounds 1 (demycarosyl-3D-beta- d-digitoxosyl-MTM) and 3 (deoliosyl-3C-beta- d-mycarosyl-MTM) show improved activity (64.8 +/- 2% and 50.3 +/- 2.5% induction of apoptosis, respectively) against the estrogen receptor (ER)-positive human breast cancer cell line MCF-7 compared with the parent drug MTM (37.8 +/- 2.5% induction of apoptosis). In addition, compounds 1 and 4 (3A-deolivosyl-MTM) show significant effects on the ER-negative human breast cancer cell line MDA-231 (63.6 +/- 2% and 12.6 +/- 2.5% induction of apoptosis, respectively), which is not inhibited by the parent drug MTM itself (2.6 +/- 1.5% induction of apoptosis), but for which chemotherapeutic agents are urgently needed.
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Affiliation(s)
- Irfan Baig
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 725 Rose Street, Lexington, Kentucky 40536-0082, USA
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Sattely ES, Fischbach MA, Walsh CT. Total biosynthesis: in vitro reconstitution of polyketide and nonribosomal peptide pathways. Nat Prod Rep 2008; 25:757-93. [DOI: 10.1039/b801747f] [Citation(s) in RCA: 151] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Peirú S, Rodríguez E, Tran CQ, Carney JR, Gramajo H. Characterization of the heterodimeric MegBIIa:MegBIIb aldo-keto reductase involved in the biosynthesis of L-mycarose from Micromonospora megalomicea. Biochemistry 2007; 46:8100-9. [PMID: 17571859 DOI: 10.1021/bi700396n] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Two putative C3-ketoreductases, MegBIIa and MegBIIb (formerly MegBII and MegDVII, respectively), homologues to members of the family 12 of aldo-keto reductase (AKR12) superfamily of enzymes, were identified in the megalomicin gene cluster from Micromonospora megalomicea. Proteins from this family are involved in the metabolism of TDP-sugars by actinomycetes. MegBIIa was originally proposed to be involved in the l-mycarose biosynthetic pathway, while MegBIIb in the l-megosamine biosynthetic pathway. In this work we have investigated the role of these proteins in the biosynthesis of dTDP-l-mycarose. In vivo analysis of the dTDP-sugar intermediates indicated that neither MegBIIa nor its homologue, MegBIIb, was a fully active enzyme by itself. Surprisingly, C3-ketoreductase activity was observed only in the presence of both MegBIIa and MegBIIb, suggesting the formation of an active complex. Copurification and size exclusion chromatography experiments confirmed that MegBIIa and MegBIIb interact forming a 1:1 heterodimeric complex. Finally, a mycarose operon containing megBIIa and megBIIb together with the other biosynthetic genes of the l-mycarose pathway was constructed and tested by bioconversion experiments in Escherichia coli. High levels of mycarosyl-erythronolide B were produced under the condition tested, confirming the role of these two proteins in this metabolic pathway.
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Affiliation(s)
- Salvador Peirú
- Microbiology Division, Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias, Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Argentina
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Salas JA, Méndez C. Engineering the glycosylation of natural products in actinomycetes. Trends Microbiol 2007; 15:219-32. [PMID: 17412593 DOI: 10.1016/j.tim.2007.03.004] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2006] [Revised: 03/07/2007] [Accepted: 03/22/2007] [Indexed: 11/24/2022]
Abstract
Bioactive natural products are frequently glycosylated with saccharide chains of different length, in which the sugars contribute to specific interactions with the biological target. Combinatorial biosynthesis approaches are being used in antibiotic-producing actinomycetes to generate derivatives with novel sugars in their architecture. Recent advances in this area indicate that glycosyltransferases involved in the biosynthesis of natural products have substrate flexibility regarding the sugar donor but also, less frequently, with respect to the aglycon acceptor. Therefore, the possibility exists of altering the glycosylation pattern of natural products, thus enabling an increase in the structural diversity of natural products.
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Affiliation(s)
- José A Salas
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, 33006 Oviedo, Spain.
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Melançon CE, Liu HW. Engineered biosynthesis of macrolide derivatives bearing the non-natural deoxysugars 4-epi-D-mycaminose and 3-n-monomethylamino-3-deoxy-D-fucose. J Am Chem Soc 2007; 129:4896-7. [PMID: 17388593 PMCID: PMC2515279 DOI: 10.1021/ja068254t] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Charles E Melançon
- Division of Medicinal Chemistry, College of Pharmacy, University of Texas at Austin, Austin, Texas 78712, USA
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Cong L, Piepersberg W. Cloning and characterization of genes encoded in dTDP-D-mycaminose biosynthetic pathway from a midecamycin-producing strain, Streptomyces mycarofaciens. Acta Biochim Biophys Sin (Shanghai) 2007; 39:187-93. [PMID: 17342257 DOI: 10.1111/j.1745-7270.2007.00265.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Two subclusters from Streptomyces mycarofaciens, a midecamycin producer, were cloned and partially sequenced. One region was located at the 5' end of the mid polyketide synthase (PKS) genes and contained the genes midA, midB and midC. The other region was at the 3' end of the PKS genes and contained midK, midI and midH. Analysis of the nucleotide sequence revealed that these genes encode dTDP-glucose synthase (midA), dTDP-glucose dehydratase (midB), aminotransferase (midC), methyltransferase (midK), glycosyltransferase (midI) and an assistant gene (midH). All of these genes are involved in the biosynthesis of dTDP-D-mycaminose, the first deoxysugar of midecamycin, and in transferring the mycaminose to the midecamycin aglycone in S. mycarofaciens. Similar to gene pairs desVIII/desVII in S. venezuelae and tylMIII/tylMII in S. fradiae, the product of midH probably functions as an auxiliary protein required by the MidI protein for efficient glycosyltransfer in midecamycin biosynthesis.
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Affiliation(s)
- Lina Cong
- College of Biology and Food Technology, Dalian Institute of Light Industry, Dalian, China.
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Fedoryshyn M, Nur-e-Alam M, Zhu L, Luzhetskyy A, Rohr J, Bechthold A. Surprising production of a new urdamycin derivative by S. fradiae Delta urdQ/R. J Biotechnol 2007; 130:32-8. [PMID: 17434221 PMCID: PMC2880504 DOI: 10.1016/j.jbiotec.2007.02.018] [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] [Received: 01/22/2007] [Accepted: 02/19/2007] [Indexed: 11/30/2022]
Abstract
A strain (S. fradiae Delta urdQ/R) with mutations in urdQ and urdR encoding a dTDP-hexose-3,4-dehydratase and a dTDP-hexose-4-ketoreductase, respectively, produces a new urdamycin analogue (urdamycin X) with changes in the polyketide structure. The structure of urdamycin X has been elucidated by NMR spectroscopy. Urdamycin X was not detectable, even in small amounts, in either S. fradiae Delta urdQ, in S. fradiae DeltaurdR or in S. fradiae A0, a mutant lacking all glycosyltransferase genes. Complementation of S. fradiae Delta urdQ/R restored urdamycin A production indicating that the mutations did not cause any polar effect.
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Affiliation(s)
- M. Fedoryshyn
- Institut für Pharmazeutische Wissenschaften, Lehrstuhl für Pharmazeutische Biologie und Biotechnologie Albert-Ludwigs-Universität Freiburg, Stefan-Meier-Strasse 19, 79104 Freiburg, Germany
| | - M. Nur-e-Alam
- Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 725 Rose street, Lexington, KY 40536-0082, USA
| | - L. Zhu
- Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 725 Rose street, Lexington, KY 40536-0082, USA
| | - A. Luzhetskyy
- Institut für Pharmazeutische Wissenschaften, Lehrstuhl für Pharmazeutische Biologie und Biotechnologie Albert-Ludwigs-Universität Freiburg, Stefan-Meier-Strasse 19, 79104 Freiburg, Germany
| | - J. Rohr
- Institut für Pharmazeutische Wissenschaften, Lehrstuhl für Pharmazeutische Biologie und Biotechnologie Albert-Ludwigs-Universität Freiburg, Stefan-Meier-Strasse 19, 79104 Freiburg, Germany
- Corresponding author (chemistry). Tel.: +1 859 323 5031; fax: +1 859 257 7564
| | - A. Bechthold
- Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 725 Rose street, Lexington, KY 40536-0082, USA
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Melançon CE, Hong L, White JA, Liu YN, Liu HW. Characterization of TDP-4-keto-6-deoxy-D-glucose-3,4-ketoisomerase from the D-mycaminose biosynthetic pathway of Streptomyces fradiae: in vitro activity and substrate specificity studies. Biochemistry 2007; 46:577-90. [PMID: 17209568 PMCID: PMC2515277 DOI: 10.1021/bi061907y] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Deoxysugars are critical structural elements for the bioactivity of many natural products. Ongoing work on elucidating a variety of deoxysugar biosynthetic pathways has paved the way for manipulation of these pathways for the generation of structurally diverse glycosylated natural products. In the course of this work, the biosynthesis of d-mycaminose in the tylosin pathway of Streptomyces fradiae was investigated. Attempts to reconstitute the entire mycaminose biosynthetic machinery in a heterologous host led to the discovery of a previously overlooked gene, tyl1a, encoding an enzyme thought to convert TDP-4-keto-6-deoxy-d-glucose to TDP-3-keto-6-deoxy-d-glucose, a 3,4-ketoisomerization reaction in the pathway. Tyl1a has now been overexpressed, purified, and assayed, and its activity has been verified by product analysis. Incubation of Tyl1a and the C-3 aminotransferase TylB, the next enzyme in the pathway, produced TDP-3-amino-3,6-dideoxy-d-glucose, confirming that these two enzymes act sequentially. Steady state kinetic parameters of the Tyl1a-catalyzed reaction were determined, and the ability of Tyl1a and TylB to process a C-2 deoxygenated substrate and a CDP-linked substrate was also demonstrated. Enzymes catalyzing 3,4-ketoisomerization of hexoses represent a new class of enzymes involved in unusual sugar biosynthesis. The fact that Tyl1a exhibits a relaxed substrate specificity holds potential for future deoxysugar biosynthetic engineering endeavors.
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Affiliation(s)
- Charles E. Melançon
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712
| | - Lin Hong
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712
| | - Jessica A. White
- Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, Texas 78712
| | - Yung-nan Liu
- Division of Medicinal Chemistry, College of Pharmacy, University of Texas at Austin, Austin, Texas 78712
| | - Hung-wen Liu
- Division of Medicinal Chemistry, College of Pharmacy, University of Texas at Austin, Austin, Texas 78712
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712
- Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, Texas 78712
- To whom correspondence and reprint requests should be addressed. Phone: 512-232-7811, Fax: 512-471-2746. E-mail:
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Anthracycline Biosynthesis: Genes, Enzymes and Mechanisms. ANTHRACYCLINE CHEMISTRY AND BIOLOGY I 2007. [DOI: 10.1007/128_2007_14] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Pérez M, Lombó F, Baig I, Braña AF, Rohr J, Salas JA, Méndez C. Combinatorial biosynthesis of antitumor deoxysugar pathways in Streptomyces griseus: Reconstitution of "unnatural natural gene clusters" for the biosynthesis of four 2,6-D-dideoxyhexoses. Appl Environ Microbiol 2006; 72:6644-52. [PMID: 17021216 PMCID: PMC1610316 DOI: 10.1128/aem.01266-06] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Combinatorial biosynthesis was applied to Streptomyces deoxysugar biosynthesis genes in order to reconstitute "unnatural natural gene clusters" for the biosynthesis of four D-deoxysugars (D-olivose, D-oliose, D-digitoxose, and D-boivinose). Expression of these gene clusters in Streptomyces albus 16F4 was used to prove the functionality of the designed clusters through the generation of glycosylated tetracenomycins. Three glycosylated tetracenomycins were generated and characterized, two of which (D-digitoxosyl-tetracenomycin C and D-boivinosyl-tetracenocmycin C) were novel compounds. The constructed gene clusters may be used to increase the capabilities of microorganisms to synthesize new deoxysugars and therefore to produce new glycosylated bioactive compounds.
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Affiliation(s)
- María Pérez
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, Oviedo, Spain
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Abstract
Glycosyltransferases (GTs) are ubiquitous enzymes that catalyze the transfer of a sugar moiety from an activated donor to an acceptor and thus play important roles in natural product biogenesis, virulence, and biomolecular recognition. Sugars are often critical for bioactivity of natural products, and methodologies for creating diverse glycoforms of these compounds are highly desirable. A recent study demonstrates that several GTs involved in natural product biosynthesis catalyze reversible reactions. Sugar exchange and aglycon exchange strategies were used to exploit this reversibility to generate >70 calicheamicin analogues.
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Affiliation(s)
- Charles E Melançon
- Department of Chemistry and Biochemistry, College of Pharmacy, University of Texas at Austin, Austin, Texas 78712, USA
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Freitag A, Li SM, Heide L. Biosynthesis of the unusual 5,5-gem-dimethyl-deoxysugar noviose: investigation of the C-methyltransferase gene cloU. MICROBIOLOGY-SGM 2006; 152:2433-2442. [PMID: 16849806 DOI: 10.1099/mic.0.28931-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The aminocoumarin antibiotic clorobiocin contains an unusual branched deoxysugar with a 5,5-gem-dimethyl structure. Inactivation of the putative C-methyltransferase gene cloU was carried out, which led to the loss of the axial methyl group at C-5 of this deoxysugar moiety. This result establishes the function of cloU, and at the same time it proves that the biosynthesis of the deoxysugar moiety of clorobiocin proceeds via a 3,5-epimerization of the dTDP-4-keto-6-deoxyglucose intermediate. The inactivation was carried out on a cosmid which contained the entire clorobiocin biosynthetic gene cluster. Expression of the modified cluster in a heterologous host led to the formation of desmethyl-clorobiocin and a structural isomer thereof. Both compounds were isolated on a preparative scale, their structures were elucidated by 1H-NMR and mass spectroscopy and their antibacterial activity was assayed.
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Affiliation(s)
- Anja Freitag
- Pharmazeutische Biologie, Pharmazeutisches Institut, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany
| | - Shu-Ming Li
- Pharmazeutische Biologie, Pharmazeutisches Institut, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany
| | - Lutz Heide
- Pharmazeutische Biologie, Pharmazeutisches Institut, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany
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Freitag A, Méndez C, Salas JA, Kammerer B, Li SM, Heide L. Metabolic engineering of the heterologous production of clorobiocin derivatives and elloramycin in Streptomyces coelicolor M512. Metab Eng 2006; 8:653-61. [PMID: 16996763 DOI: 10.1016/j.ymben.2006.07.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2006] [Revised: 07/21/2006] [Accepted: 07/24/2006] [Indexed: 11/24/2022]
Abstract
The aminocoumarin antibiotic clorobiocin is a potent inhibitor of bacterial gyrase. Two new analogs of clorobiocin could be obtained by deletion of a methyltransferase gene, involved in deoxysugar biosynthesis, from the biosynthetic gene cluster of clorobiocin, followed by expression of the modified cluster in the heterologous host Streptomyces coelicolor M512. However, only low amounts of the desired glycosides were formed, and aminocoumarins accumulated predominantly in form of aglyca. In the present study, we clarified the limiting steps for aminocoumarin glycoside formation, and devised strategies to improve glycosylation efficiency. Heterologous expression of a partial elloramycin biosynthetic gene cluster indicated that the rate of dTDP-L-rhamnose synthesis, rather than the rate of glycosyl transfer, was limiting for glycoside formation in this strain. Introduction of plasmid pRHAM which contains four genes from the oleandomycin biosynthetic gene cluster, directing the synthesis of dTDP-rhamnose, led to a 26-fold increase of the production of glycosylated aminocoumarins. Expression of the 4-ketoreductase gene oleU alone resulted in an 8-fold increase. Structural investigation of the resulting deoxysugars confirmed that both the endogeneous and the heterologous pathway involve a 3,5-epimerization of the deoxysugar, a hypothesis which had recently been questioned.
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Affiliation(s)
- Anja Freitag
- Pharmazeutisches Institut, Eberhard-Karls-Universität Tübingen, Germany
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