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Wei B, Luo X, Zhou ZY, Hu GA, Li L, Lin HW, Wang H. Discovering the secondary metabolic potential of Saccharothrix. Biotechnol Adv 2024; 70:108295. [PMID: 38052345 DOI: 10.1016/j.biotechadv.2023.108295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 11/08/2023] [Accepted: 11/25/2023] [Indexed: 12/07/2023]
Abstract
Rare actinomycetes are highly valued as potential sources of novel bioactive secondary metabolites. Among these rare actinomycetes, the genus Saccharothrix is particularly noteworthy due to its ability to produce a diverse range of bioactive secondary metabolites. With the continuous sequencing of bacterial genomes and the rapid development of bioinformatics technologies, our knowledge of the secondary metabolic potential of Saccharothrix can become more comprehensive, but this space has not been reviewed or explored. This review presents a detailed overview of the chemical structures and bioactivities of 138 Saccharothrix-derived secondary metabolites, which are classified into five distinct groups based on their biosynthetic pathways. Furthermore, we delve into experimentally characterized biosynthetic pathways of nine bioactive metabolites. By utilizing a combination of cheminformatic and bioinformatic approaches, we attempted to establish connections between the metabolite families and the biosynthetic gene cluster families encoded by Saccharothrix strains. Our analysis provides a comprehensive perspective on the secondary metabolites that can be linked to corresponding BGCs and highlights the underexplored biosynthetic potential of Saccharothrix. This review also provides guidance for the targeted discovery and biosynthesis of novel natural products from Saccharothrix.
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Affiliation(s)
- Bin Wei
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Xian Luo
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Zhen-Yi Zhou
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Gang-Ao Hu
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Lei Li
- Research Center for Marine Drugs, Department of Pharmacy, Ren Ji Hospital, School of Medicine, State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai 200127, China.
| | - Hou-Wen Lin
- Research Center for Marine Drugs, Department of Pharmacy, Ren Ji Hospital, School of Medicine, State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai 200127, China.
| | - Hong Wang
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China.
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Liu S, Wang T, Lu Q, Li F, Wu G, Jiang Z, Habden X, Liu L, Zhang X, Lukianov DA, Osterman IA, Sergiev PV, Dontsova OA, Sun C. Bioprospecting of Soil-Derived Actinobacteria Along the Alar-Hotan Desert Highway in the Taklamakan Desert. Front Microbiol 2021; 12:604999. [PMID: 33790875 PMCID: PMC8005632 DOI: 10.3389/fmicb.2021.604999] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 02/22/2021] [Indexed: 02/04/2023] Open
Abstract
Taklamakan desert is known as the largest dunefield in China and as the second largest shifting sand desert in the world. Although with long history and glorious culture, the Taklamakan desert remains largely unexplored and numerous microorganisms have not been harvested in culture or taxonomically identified yet. The main objective of this study is to explore the diversity, novelty, and pharmacological potential of the cultivable actinomycetes from soil samples at various sites along the Alar-Hotan desert highway in the Taklamakan desert. A total of 590 actinobacterial strains were recovered by the culture-dependent approach. Phylogenetic analysis based on 16S ribosomal RNA (rRNA) gene sequences unveiled a significant level of actinobacterial diversity with 55 genera distributed in 27 families of 12 orders. Thirty-six strains showed relatively low 16S rRNA similarities (<98.65%) with validly described species, among which four strains had already been characterized as novel taxa by our previous research. One hundred and forty-six actinobacterial isolates were selected as representatives to evaluate the antibacterial activities and mechanism of action by the paper-disk diffusion method and a double fluorescent protein reporter "pDualrep2" system, respectively. A total of 61 isolates exhibited antagonistic activity against the tested "ESKAPE" pathogens, among which seven strains could produce bioactive metabolites either to be able to block translation machinery or to induce SOS-response in the pDualrep2 system. Notably, Saccharothrix sp. 16Sb2-4, harboring a promising antibacterial potential with the mechanism of interfering with protein translation, was analyzed in detail to gain deeper insights into its bioactive metabolites. Through ultra-performance liquid chromatography (UPLC)-quadrupole time-of-flight (QToF)-MS/MS based molecular networking analysis and databases identification, four families of compounds (1-16) were putatively identified. Subsequent bioassay-guided separation resulted in purification of four 16-membered macrolide antibiotics, aldgamycin H (8), aldgamycin K (9), aldgamycin G (10), and swalpamycin B (11), and their structures were elucidated by HR-electrospray ionization source (ESI)-MS and NMR spectroscopy. All compounds 8-11 displayed antibacterial activities by inhibiting protein synthesis in the pDualrep2 system. In conclusion, this work demonstrates that Taklamakan desert is a potentially unique reservoir of versatile actinobacteria, which can be a promising source for discovery of novel species and diverse bioactive compounds.
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Affiliation(s)
- Shaowei Liu
- Department of Microbial Chemistry, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Ting Wang
- Department of Microbial Chemistry, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Qinpei Lu
- Department of Microbial Chemistry, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Feina Li
- Department of Microbial Chemistry, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Gang Wu
- Department of Microbial Chemistry, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Zhongke Jiang
- Department of Microbial Chemistry, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xugela Habden
- College of Life Science, Xinjiang Normal University, Urumchi, China
| | - Lin Liu
- School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Xiaolin Zhang
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Dmitry A. Lukianov
- Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, Russia
| | - Ilya A. Osterman
- Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, Russia
- Department of Chemistry, A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Petr V. Sergiev
- Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, Russia
- Department of Chemistry, A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Olga A. Dontsova
- Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, Russia
- Department of Chemistry, A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Chenghang Sun
- Department of Microbial Chemistry, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
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Waldman AJ, Ng TL, Wang P, Balskus EP. Heteroatom-Heteroatom Bond Formation in Natural Product Biosynthesis. Chem Rev 2017; 117:5784-5863. [PMID: 28375000 PMCID: PMC5534343 DOI: 10.1021/acs.chemrev.6b00621] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Natural products that contain functional groups with heteroatom-heteroatom linkages (X-X, where X = N, O, S, and P) are a small yet intriguing group of metabolites. The reactivity and diversity of these structural motifs has captured the interest of synthetic and biological chemists alike. Functional groups containing X-X bonds are found in all major classes of natural products and often impart significant biological activity. This review presents our current understanding of the biosynthetic logic and enzymatic chemistry involved in the construction of X-X bond containing functional groups within natural products. Elucidating and characterizing biosynthetic pathways that generate X-X bonds could both provide tools for biocatalysis and synthetic biology, as well as guide efforts to uncover new natural products containing these structural features.
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Affiliation(s)
- Abraham J. Waldman
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, United States
| | - Tai L. Ng
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, United States
| | - Peng Wang
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, United States
| | - Emily P. Balskus
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, United States
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Shi Y, Gao S. Recent advances of synthesis of fluorenone and fluorene containing natural products. Tetrahedron 2016. [DOI: 10.1016/j.tet.2016.02.022] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Cai S, Xiao Z, Ou J, Shi Y, Gao S. A photo-induced C–C bond formation methodology to construct tetrahydrofluorenones and their related structures. Org Chem Front 2016. [DOI: 10.1039/c5qo00392j] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A metal-free, photo-induced C–C bond formation methodology was developed to construct tetrahydrofluorenones and their related structures.
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Affiliation(s)
- Shujun Cai
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200062
- China
| | - Zheming Xiao
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200062
- China
| | - Jinjie Ou
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200062
- China
| | - Yingbo Shi
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200062
- China
| | - Shuanhu Gao
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200062
- China
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6
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Herzon SB, Woo CM. The diazofluorene antitumor antibiotics: Structural elucidation, biosynthetic, synthetic, and chemical biological studies. Nat Prod Rep 2012; 29:87-118. [DOI: 10.1039/c1np00052g] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Zitouni A, Boudjella H, Lamari L, Badji B, Mathieu F, Lebrihi A, Sabaou N. Nocardiopsis and Saccharothrix genera in Saharan soils in Algeria: isolation, biological activities and partial characterization of antibiotics. Res Microbiol 2005; 156:984-93. [PMID: 16081249 DOI: 10.1016/j.resmic.2005.05.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2004] [Revised: 05/10/2005] [Accepted: 05/17/2005] [Indexed: 11/26/2022]
Abstract
Twenty-five soil samples were collected in the Algerian Sahara and analyzed to isolate rare actinomycetes. Eighty-six isolates with the same Nocardiopsis or Saccharothrix morphology were isolated on humic-vitamin B agar medium using dilution techniques and several antibiotics as selective agents. Certain of these antibiotics seemed to be very selective for some phenotypes. Morphological and chemotaxonomic characteristics led to identifying 54 isolates belonging to the Nocardiopsis genus and 32 isolates belonging to the Saccharothrix genus. An assessment of the antimicrobial properties of the isolates showed activities against Gram-positive bacteria, fungi and yeasts. Saccharothrix isolates possessed better antifungal activity than Nocardiopsis. One of them, labeled SA 103, was therefore selected for identification of its antifungal antibiotic activities. Production of overall antifungal and antibacterial activities was checked on the complex medium ISP2 and a synthetic medium (SM) that contains glucose or starch as carbon source, and ammonium or nitrate as nitrogen source. The SM medium containing ammonium sulfate (0.2%), supplemented with starch (0.5%) and yeast extract (0.3%), was retained for production of antibiotics. Active substances were purified by a G25-80 Sephadex column and reverse phase HPLC. Two pure substances were obtained and named ZA01 and ZA02; they were characterized on the basis of combined data resulting from chemical tests, UV visibile and IR spectra and mass spectrometry. The two antibiotics were found to be related and were partially characterized as nucleotidic or nucleosidic antibiotics. Their structures consisted of a chain of three sugar units linked to an aromatic base containing a phosphate residue.
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Affiliation(s)
- Abdelghani Zitouni
- Laboratoire de Recherche sur les Produits Bioactifs et la Valorisation de la Biomasse, Ecole Normale Supérieure de Kouba, B.P. 92, 16 050 Vieux-Kouba, Alger, Algeria
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Lee JY, Moon SS, Yun BS, Yoo ID, Hwang BK. Thiobutacin, a novel antifungal and antioomycete antibiotic from Lechevalieria aerocolonigenes. JOURNAL OF NATURAL PRODUCTS 2004; 67:2076-2078. [PMID: 15620255 DOI: 10.1021/np049786v] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A novel butanoic acid, thiobutacin (1), 4-(2-aminophenyl)-4-oxo-2-methylthiobutanoic acid (C11H13NO3S), was isolated from the culture broth of a soil actinomycete, Lechevalieria aerocolonigenes strain VK-A9. The structure of thiobutacin (1) was elucidated on the basis of the extensive 2D NMR spectral data including 1H-1H COSY, HMBC, HMQC, ROESY, and NOESY. Thiobutacin (1) showed antioomycete and antifungal activity against phytopathogenic Phytophthora capsici and Botrytis cinerea and the yeast Saccharomyces cerevisiae.
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Affiliation(s)
- Jung Yeop Lee
- Division of Bioscience and Technology, College of Life and Environmental Sciences, Korea University, Seoul 136-713, Korea
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9
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Knölker HJ, Reddy KR. Isolation and synthesis of biologically active carbazole alkaloids. Chem Rev 2002; 102:4303-427. [PMID: 12428991 DOI: 10.1021/cr020059j] [Citation(s) in RCA: 1073] [Impact Index Per Article: 48.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hans-Joachim Knölker
- Institut für Organische Chemie, Technische Universität Dresden, Bergstrasse 66, 01069 Dresden, Germany
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Barluenga J, Fernández-Rodríguez MA, Aguilar E. Cycloaddition reactions of alkoxy alkynyl Fischer carbene complexes with o-quinodimethanes (oQDMs). Org Lett 2002; 4:3659-62. [PMID: 12375912 DOI: 10.1021/ol026600f] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] The reaction of o-quinodimethanes (oQDMs) with alkoxy alkynyl Fischer carbene complexes is highly dependent on the carbene complex. Thus, for arylalkynyl carbene complexes, the initial [4 + 2]-cycloadduct evolves opening a new entry to the benzo[b]fluorene skeleton, which is present in many natural products. However, for alkenylalkynyl carbene complexes, the reaction takes place through the double bond, instead of the triple bond, in an unprecedented fashion, leading to new functionalized alkynyl carbene complexes.
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Affiliation(s)
- José Barluenga
- Instituto Universitario de Química Organometálica "Enrique Moles", Unidad Asociada al C.S.I.C., Universidad de Oviedo, C/Julián Clavería, 8, 33006 Oviedo, Spain.
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11
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Affiliation(s)
- Steven J. Gould
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331
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12
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Gould SJ, Melville CR, Cone MC, Chen J, Carney JR. Kinamycin Biosynthesis. Synthesis, Isolation, and Incorporation of Stealthin C, an Aminobenzo[b]fluorene. J Org Chem 1997; 62:320-324. [PMID: 11671405 DOI: 10.1021/jo961486y] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A new intermediate in the biosynthesis of the benzo[b]fluorene antibiotic, kinamycin D, has been identified. 11-Amino-4,5,9-trihydroxy-2-methyl-10H-benzo[b]fluoren-10-one was synthesized and shown to be present in extracts of Streptomyces murayamaensisfermentations. A deuterated sample was prepared and shown to be specifically incorporated into kinamycin D. This new intermediate, now named stealthin C, is also the probable hydroxylation substrate for the biosynthesis of stealthin A by S. viridochromogenes.
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Affiliation(s)
- Steven J. Gould
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331
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Gould SJ, O'Hare T, Seaton P, Soodsma J, Tang Z. Kinamycin acetyltransferase I from Streptomyces murayamaensis, an apparently large, membrane-associated enzyme. Bioorg Med Chem 1996; 4:987-94. [PMID: 8831968 DOI: 10.1016/0968-0896(96)00097-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Identification and initial characterization of an apparently large, membrane-associated multifunctional enzyme, kinamycin acetyltransferase I (KAT I), is described. KAT I activity was enriched 29-fold over the level in cell-free extracts of Streptomyces murayamaensis. Two acetyltransferase activities catalyzing acetyl coenzyme A dependent conversion of kinamycin F and E to kinamycin E and D, respectively, were inseparable in the course of the partial purification. Partial purification involved separation of KAT I from cytosolic proteins by differential ultracentrifugation, solubilization with 0.5% CHAPS zwitterionic detergent followed by ultracentrifugation, and Sephacryl S400 gel filtration chromatography of the resulting supernatant.
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Affiliation(s)
- S J Gould
- Department of Chemistry, Oregon State University, Corvallis 97331-4003, USA
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Knölker HJ, O' Sullivan N. Indoloquinones, Part 2 Palladium-promoted synthesis of a 7-deoxyprekinamycin isomer. Tetrahedron Lett 1994. [DOI: 10.1016/0040-4039(94)88322-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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15
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Indoloquinones - 3. Palladium-promoted synthesis of hydroxy-substituted 5-Cyano-5H-benzo[b]carbazole-6, 11-diones. Tetrahedron 1994. [DOI: 10.1016/s0040-4020(01)85701-x] [Citation(s) in RCA: 131] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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17
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O'Sullivan PJ, Moreno R, Murphy WS. Regioselective synthesis of the kinamycin ABCD ring system. Tetrahedron Lett 1992. [DOI: 10.1016/s0040-4039(00)93989-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
The study of antibiotics and other fermentation products has shown that a seemingly unlimited number of compounds with diverse structures are produced by microorganisms. The continued high rate of discovery of new chemical entities, in the light of the abundance of microbial products already described, is due to creative screening procedures that incorporate such features as the emphasis on unusual microorgnaisms, their special propagation and fermentation requirements, supersensitive and highly selective assays, genetic engineering both for the biosynthesis of new compounds and in the development of screening systems, early in vivo evaluation, improved isolation techniques, modern procedures for structure determination, computer-assisted identification, and an efficient multidisciplinary approach. This review focuses on the genesis and development of the gamut of methodologies that have led to the successful detection of the wide variety of novel secondary metabolites that include antibacterial, antigungal, antiviral and antitumour antibiotics, enzyme inhibitors, pharmacologically and immunologically active agents, products useful in agriculture and animal husbandry, microbial regulators, and other compounds for which no bioactive role has yet been found.
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Affiliation(s)
- C M Franco
- Microbiology Department, Hoechst Centre for Basic Research, Hoechst India Limited, Lal Bahadur Shastri Marg, Mulund, Bombay
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Regioselective diels-alder reactions of n-cyanoindole-4,7-diones: Elaboration of the a-ring of the kinamycins on a bc ring template. Tetrahedron Lett 1990. [DOI: 10.1016/s0040-4039(00)97939-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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20
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N-cyanoindoles and n-cyanoindole-4,7-diones: Construction of a bc ring synthon for the kinamycins. Tetrahedron Lett 1990. [DOI: 10.1016/s0040-4039(00)97443-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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