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Singh SB, Occi J, Ondeyka J, Barrett JF, Masurekar P, Motyl M, Gill C, Salituro G. Antibacterial and mechanism of action studies of boxazomycin A. J Antibiot (Tokyo) 2024:10.1038/s41429-024-00757-9. [PMID: 39090325 DOI: 10.1038/s41429-024-00757-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 04/20/2024] [Accepted: 06/18/2024] [Indexed: 08/04/2024]
Abstract
Boxazomycins A-C are potent broad-spectrum antibiotics isolated from Actinomycetes strain G495-1 in 1987. We now report that boxazomycin A inhibits bacterial growth by selectively inhibiting protein synthesis, its effect is bacteriostatic, and it is equally active against drug resistant bacterial strains. No cross-resistance to protein synthesis inhibitors was observed suggesting that its inhibition is distinct from clinical protein synthesis inhibitors. We also report in vivo efficacy in a Staphylococcus aureus murine infection model supported by corresponding pharmacokinetic studies.
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Affiliation(s)
- Sheo B Singh
- Merck & Co. Inc., Rahway, NJ, 07065, USA.
- Charles A Dana Research Institute of Scientist Emeriti, Drew University, Madison, NJ, 07054, USA.
- Department of chemistry & Chemical Biology, Stevens Institute of Technology, Hoboken, NJ, 07030, USA.
| | - James Occi
- Merck & Co. Inc., Rahway, NJ, 07065, USA
- Center for Vector Biology, Rutgers University, New Brunswick, NJ, 08901, USA
| | | | | | | | - Mary Motyl
- Merck & Co. Inc., Rahway, NJ, 07065, USA
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2
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Pfeiffer IPM, Schröder MP, Mordhorst S. Opportunities and challenges of RiPP-based therapeutics. Nat Prod Rep 2024; 41:990-1019. [PMID: 38411278 DOI: 10.1039/d3np00057e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
Covering: up to 2024Ribosomally synthesised and post-translationally modified peptides (RiPPs) comprise a substantial group of peptide natural products exhibiting noteworthy bioactivities ranging from antiinfective to anticancer and analgesic effects. Furthermore, RiPP biosynthetic pathways represent promising production routes for complex peptide drugs, and the RiPP technology is well-suited for peptide engineering to produce derivatives with specific functions. Thus, RiPP natural products possess features that render them potentially ideal candidates for drug discovery and development. Nonetheless, only a small number of RiPP-derived compounds have successfully reached the market thus far. This review initially outlines the therapeutic opportunities that RiPP-based compounds can offer, whilst subsequently discussing the limitations that require resolution in order to fully exploit the potential of RiPPs towards the development of innovative drugs.
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Affiliation(s)
- Isabel P-M Pfeiffer
- University of Tübingen, Pharmaceutical Institute, Department of Pharmaceutical Biology, Auf der Morgenstelle 8, 72076 Tübingen, Germany.
| | - Maria-Paula Schröder
- University of Tübingen, Pharmaceutical Institute, Department of Pharmaceutical Biology, Auf der Morgenstelle 8, 72076 Tübingen, Germany.
| | - Silja Mordhorst
- University of Tübingen, Pharmaceutical Institute, Department of Pharmaceutical Biology, Auf der Morgenstelle 8, 72076 Tübingen, Germany.
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3
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Singh SB, Miesel L, Kramer S, Xu L, Li F, Lan J, Lipari P, Polishook JD, Liu G, Liang L, Flattery AM. Nocathiacin, Thiazomycin, and Polar Analogs Are Highly Effective Agents against Toxigenic Clostridioides difficile. JOURNAL OF NATURAL PRODUCTS 2022; 85:1141-1146. [PMID: 35380836 DOI: 10.1021/acs.jnatprod.2c00093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Clostridioides difficile is a commensal Gram-positive gut bacterium that causes C. difficile-associated diarrhea. Currently available antibacterial therapeutic treatment options are effective except for the repeated recurrences significantly burdening the health care system and causing mortality. The development of new therapeutic modalities including new effective antibiotics with a low rate of recurrence has been unpredictive and exceedingly challenging, requiring continued profiling of many new classes of antibiotics. Nocathiacins and thiazomycins are a class of thiazolyl peptides exhibiting potent and selective broad-spectrum Gram-positive activity including activity against the anaerobe C. difficile. These compounds showed MIC values of 0.015-0.06 μg/mL against C. difficile with more than 100-200-fold selectivity versus commensurate Gram-negative Bacteroides fragilis. Nocathiacin I and one of its analogs exhibited potent in vivo efficacy in the gold-standard hamster model of C. difficile infection, providing 100% protection in this lethal model at 6.25 mg/kg orally twice daily. The efficacy was corroborated by robust reduction of cecum C. difficile burden and proportionate exposure of the compounds in the cecum contents without any systemic absorption. In this paper, details of the results of in vitro, in vivo, pharmacodynamics, and pharmacokinetic studies have been described.
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Affiliation(s)
- Sheo B Singh
- Discovery Chemistry, Merck & Co., Inc., Kenilworth, New Jersey 07065, United States
| | - Lynn Miesel
- Antibacterial Discovery, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Susanne Kramer
- In Vivo Pharmacology, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Libo Xu
- Discovery Chemistry, Merck & Co., Inc., Kenilworth, New Jersey 07065, United States
| | - Fangbio Li
- Pharmacokinetics, Merck & Co., Inc., Kenilworth, New Jersey 07065, United States
| | - Jing Lan
- Pharmacokinetics, Merck & Co., Inc., Kenilworth, New Jersey 07065, United States
| | - Phillip Lipari
- In Vivo Pharmacology, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Jon D Polishook
- In Vivo Pharmacology, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Gongjie Liu
- In Vivo Pharmacology, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Lianzhu Liang
- In Vivo Pharmacology, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Amy M Flattery
- In Vivo Pharmacology, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
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4
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Bailly C. The bacterial thiopeptide thiostrepton. An update of its mode of action, pharmacological properties and applications. Eur J Pharmacol 2022; 914:174661. [PMID: 34863996 DOI: 10.1016/j.ejphar.2021.174661] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 11/29/2021] [Indexed: 12/20/2022]
Abstract
The bacterial thiopeptide thiostrepton (TS) is used as a veterinary medicine to treat bacterial infections. TS is a protein translation inhibitor, essentially active against Gram-positive bacteria and some Gram-negative bacteria. In procaryotes, TS abrogates binding of GTPase elongation factors to the 70S ribosome, by altering the structure of rRNA-L11 protein complexes. TS exerts also antimalarial effects by disrupting protein synthesis in the apicoplast genome of Plasmodium falciparum. Interestingly, the drug targets both the infectious pathogen (bacteria or parasite) and host cell, by inducing endoplasmic reticulum stress-mediated autophagy which contributes to enhance the host cell defense. In addition, TS has been characterized as a potent chemical inhibitor of the oncogenic transcription factor FoxM1, frequently overexpressed in cancers or other diseases. The capacity of TS to crosslink FoxM1, and a few other proteins such as peroxiredoxin 3 (PRX3) and the 19S proteasome, contributes to the anticancer effects of the thiopeptide. The anticancer activities of TS evidenced using diverse tumor cell lines, in vivo models and drug combinations are reviewed here, together with the implicated targets and mechanisms. The difficulty to formulate TS is a drag on the pharmaceutical development of the natural product. However, the design of hemisynthetic analogues and the use of micellar drug delivery systems should facilitate a broader utilization of the compound in human and veterinary medicines. This review shed light on the many pharmacological properties of TS, with the objective to promote its use as a pharmacological tool and medicinal product.
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Affiliation(s)
- Christian Bailly
- OncoWitan, Scientific Consulting Office, Lille, Wasquehal, 59290, France.
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5
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Secondary Metabolites of the Genus Amycolatopsis: Structures, Bioactivities and Biosynthesis. Molecules 2021; 26:molecules26071884. [PMID: 33810439 PMCID: PMC8037709 DOI: 10.3390/molecules26071884] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 03/18/2021] [Accepted: 03/23/2021] [Indexed: 12/13/2022] Open
Abstract
Actinomycetes are regarded as important sources for the generation of various bioactive secondary metabolites with rich chemical and bioactive diversities. Amycolatopsis falls under the rare actinomycete genus with the potential to produce antibiotics. In this review, all literatures were searched in the Web of Science, Google Scholar and PubMed up to March 2021. The keywords used in the search strategy were “Amycolatopsis”, “secondary metabolite”, “new or novel compound”, “bioactivity”, “biosynthetic pathway” and “derivatives”. The objective in this review is to summarize the chemical structures and biological activities of secondary metabolites from the genus Amycolatopsis. A total of 159 compounds derived from 8 known and 18 unidentified species are summarized in this paper. These secondary metabolites are mainly categorized into polyphenols, linear polyketides, macrolides, macrolactams, thiazolyl peptides, cyclic peptides, glycopeptides, amide and amino derivatives, glycoside derivatives, enediyne derivatives and sesquiterpenes. Meanwhile, they mainly showed unique antimicrobial, anti-cancer, antioxidant, anti-hyperglycemic, and enzyme inhibition activities. In addition, the biosynthetic pathways of several potent bioactive compounds and derivatives are included and the prospect of the chemical substances obtained from Amycolatopsis is also discussed to provide ideas for their implementation in the field of therapeutics and drug discovery.
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6
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Vinogradov AA, Suga H. Introduction to Thiopeptides: Biological Activity, Biosynthesis, and Strategies for Functional Reprogramming. Cell Chem Biol 2020; 27:1032-1051. [PMID: 32698017 DOI: 10.1016/j.chembiol.2020.07.003] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 06/21/2020] [Accepted: 07/01/2020] [Indexed: 12/16/2022]
Abstract
Thiopeptides (also known as thiazolyl peptides) are structurally complex natural products with rich biological activities. Known for over 70 years for potent killing of Gram-positive bacteria, thiopeptides are experiencing a resurgence of interest in the last decade, primarily brought about by the genomic revolution of the 21st century. Every area of thiopeptide research-from elucidating their biological function and biosynthesis to expanding their structural diversity through genome mining-has made great strides in recent years. These advances lay the foundation for and inspire novel strategies for thiopeptide engineering. Accordingly, a number of diverse approaches are being actively pursued in the hope of developing the next generation of natural-product-inspired therapeutics. Here, we review the contemporary understanding of thiopeptide biological activities, biosynthetic pathways, and approaches to structural and functional reprogramming, with a special focus on the latter.
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Affiliation(s)
- Alexander A Vinogradov
- Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
| | - Hiroaki Suga
- Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
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7
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Ben Said L, Emond-Rheault JG, Soltani S, Telhig S, Zirah S, Rebuffat S, Diarra MS, Goodridge L, Levesque RC, Fliss I. Phenomic and genomic approaches to studying the inhibition of multiresistant Salmonella enterica by microcin J25. Environ Microbiol 2020; 22:2907-2920. [PMID: 32363677 DOI: 10.1111/1462-2920.15045] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 04/15/2020] [Accepted: 04/25/2020] [Indexed: 12/22/2022]
Abstract
In livestock production, antibiotics are used to promote animal growth, control infections and thereby increase profitability. This practice has led to the emergence of multiresistant bacteria such as Salmonella, of which some serovars are disseminated in the environment. The objective of this study is to evaluate microcin J25 as an inhibitor of Salmonella enterica serovars of various origins including human, livestock and food. Among the 116 isolates tested, 37 (31.8%) were found resistant to at least one antibiotic, and 28 were multiresistant with 19 expressing the penta-resistant phenotype ACSSuT. Microcin J25 inhibited all isolates, with minimal inhibitory concentration values ranging from 0.06 μg/ml (28.4 nM) to 400 μg/ml (189 μM). Interestingly, no cross-resistance was found between microcin J25 and antibiotics. Multiple sequence alignments of genes encoding for the different proteins involved in the recognition and transport of microcin J25 showed that only ferric-hydroxamate uptake is an essential determinant for susceptibility of S. enterica to microcin J25. Examination of Salmonella strains exposed to microcin J25 by transmission electronic microscopy showed for the first-time involvement of a pore formation mechanism. Microcin J25 was a strong inhibitor of several multiresistant isolates of Salmonella and may have a great potential as an alternative to antibiotics.
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Affiliation(s)
- Laila Ben Said
- Institute of Nutrition and Functional Foods, Université Laval, Québec, Quebec, G1V 0A6, Canada
| | | | - Samira Soltani
- Institute of Nutrition and Functional Foods, Université Laval, Québec, Quebec, G1V 0A6, Canada
| | - Sofiane Telhig
- Institute of Nutrition and Functional Foods, Université Laval, Québec, Quebec, G1V 0A6, Canada.,Muséum National d'Histoire Naturelle, Centre National de la Recherche Scientifique, Laboratory of Communication Molecules and Adaptation of Micro-organisms, UMR 7245 CNRS-MNHN, Paris, CP 54, 57 rue Cuvier 75005, France
| | - Séverine Zirah
- Muséum National d'Histoire Naturelle, Centre National de la Recherche Scientifique, Laboratory of Communication Molecules and Adaptation of Micro-organisms, UMR 7245 CNRS-MNHN, Paris, CP 54, 57 rue Cuvier 75005, France
| | - Sylvie Rebuffat
- Muséum National d'Histoire Naturelle, Centre National de la Recherche Scientifique, Laboratory of Communication Molecules and Adaptation of Micro-organisms, UMR 7245 CNRS-MNHN, Paris, CP 54, 57 rue Cuvier 75005, France
| | - Moussa Sory Diarra
- Guelph Research and Development Center, Agriculture and Agri-Food Canada, 93 Stone Road West, Guelph, Ontario, N1G 5C9, Canada
| | - Lawrence Goodridge
- Department of Food Science and Agriculture, McGill University, Ste Anne de Bellevue, Québec, Quebec, H9X3V9, Canada
| | - Roger C Levesque
- Institute of Integrative Biology and Systems, Université Laval, QC, Québec, G1V 0A6, Canada
| | - Ismail Fliss
- Institute of Nutrition and Functional Foods, Université Laval, Québec, Quebec, G1V 0A6, Canada
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Christy MP, Johnson T, McNerlin CD, Woodard J, Nelson AT, Lim B, Hamilton TL, Freiberg KM, Siegel D. Total Synthesis of Micrococcin P1 through Scalable Thiazole Forming Reactions of Cysteine Derivatives and Nitriles. Org Lett 2020; 22:2365-2370. [DOI: 10.1021/acs.orglett.0c00202] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Mitchell P. Christy
- Department of Chemistry & Biochemistry, University of California—San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Trevor Johnson
- Department of Chemistry & Biochemistry, University of California—San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Clare D. McNerlin
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California-San Diego, 9500 Gilman Drive, La Jolla, California 92093-0934, United States
| | - John Woodard
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California-San Diego, 9500 Gilman Drive, La Jolla, California 92093-0934, United States
| | - Andrew T. Nelson
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street, A5300, Austin, Texas 78712-1224, United States
- School of Medicine, University of Texas Medical Branch, 301 University Boulevard, Galveston, Texas 77555, United States
| | - Bryant Lim
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California-San Diego, 9500 Gilman Drive, La Jolla, California 92093-0934, United States
| | - Tiffany L. Hamilton
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California-San Diego, 9500 Gilman Drive, La Jolla, California 92093-0934, United States
| | - Kaitlyn M. Freiberg
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California-San Diego, 9500 Gilman Drive, La Jolla, California 92093-0934, United States
| | - Dionicio Siegel
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California-San Diego, 9500 Gilman Drive, La Jolla, California 92093-0934, United States
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9
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Natural thiopeptides as a privileged scaffold for drug discovery and therapeutic development. Med Chem Res 2019. [DOI: 10.1007/s00044-019-02361-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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10
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Zhao P, Xue Y, Gao W, Li J, Zu X, Fu D, Feng S, Bai X, Zuo Y, Li P. Actinobacteria-Derived peptide antibiotics since 2000. Peptides 2018; 103:48-59. [PMID: 29567053 DOI: 10.1016/j.peptides.2018.03.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 03/16/2018] [Accepted: 03/18/2018] [Indexed: 11/23/2022]
Abstract
Members of the Actinobacteria, including Streptomyces spp., Kutzneria sp. Actinoplanes spp., Actinomycete sp., Nocardia sp., Brevibacteriumsp.,Actinomadura spp., Micromonospora sp., Amycolatopsis spp., Nonomuraea spp., Nocardiopsis spp., Marinactinospora sp., Rhodococcus sp., Lentzea sp., Actinokineospora sp., Planomonospora sp., Streptomonospora sp., and Microbacterium sp., are an important source of structurally diverse classes of short peptides of ∼30 residues or fewer that will likely play an important role in new antibiotic development and discovery. Additionally, many have unique structures that make them recalcitrant to traditional modes of drug resistance via novel mechanisms, and these are ideal therapeutic tools and potential alternatives to current antibiotics. The need for novel antibiotic is urgent, and this review summarizes 199 Actinobacteria compounds published since 2000, including 35 cyclic lipopeptides containing piperazic or pipecolic acids, eight aromatic peptides, five glycopeptides, 21 bicyclic peptides, 44 other cyclic lipopeptides, five linear lipopeptides, six 2,5-diketopiperazines, one dimeric peptide, four nucleosidyl peptides, two thioamide-containing peptides, 25 thiopeptides, nine lasso peptides, and 34 typical cyclic peptides. The current and potential therapeutic applications of these peptides, including their structure, antituberculotic, antibacterial, antifungal, antiviral, anti-brugia, anti-plasmodial, and anti-trypanosomal activities, are discussed.
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Affiliation(s)
- Pengchao Zhao
- College of Medical Technology and Engineering, Henan University of Science and Technology, Luoyang, 471023, China
| | - Yun Xue
- College of Medical Technology and Engineering, Henan University of Science and Technology, Luoyang, 471023, China.
| | - Weina Gao
- College of Medical Technology and Engineering, Henan University of Science and Technology, Luoyang, 471023, China
| | - Jinghua Li
- College of Medical Technology and Engineering, Henan University of Science and Technology, Luoyang, 471023, China
| | - Xiangyang Zu
- College of Medical Technology and Engineering, Henan University of Science and Technology, Luoyang, 471023, China
| | - Dongliao Fu
- College of Medical Technology and Engineering, Henan University of Science and Technology, Luoyang, 471023, China
| | - Shuxiao Feng
- College of Chemical Engineering and Pharmacy, Henan University of Science and Technology, Luoyang, 471023, China
| | - Xuefei Bai
- College of Medical Technology and Engineering, Henan University of Science and Technology, Luoyang, 471023, China
| | - Yanjun Zuo
- College of Medical Technology and Engineering, Henan University of Science and Technology, Luoyang, 471023, China
| | - Ping Li
- College of Medical Technology and Engineering, Henan University of Science and Technology, Luoyang, 471023, China
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Abstract
Covering: 2006 to 2017Actinomycetes have been, for decades, one of the most important sources for the discovery of new antibiotics with an important number of drugs and analogs successfully introduced in the market and still used today in clinical practice. The intensive antibacterial discovery effort that generated the large number of highly potent broad-spectrum antibiotics, has seen a dramatic decline in the large pharma industry in the last two decades resulting in a lack of new classes of antibiotics with novel mechanisms of action reaching the clinic. Whereas the decline in the number of new chemical scaffolds and the rediscovery problem of old known molecules has become a hurdle for industrial natural products discovery programs, new actinomycetes compounds and leads have continued to be discovered and developed to the preclinical stages. Actinomycetes are still one of the most important sources of chemical diversity and a reservoir to mine for novel structures that is requiring the integration of diverse disciplines. These can range from novel strategies to isolate species previously not cultivated, innovative whole cell screening approaches and on-site analytical detection and dereplication tools for novel compounds, to in silico biosynthetic predictions from whole gene sequences and novel engineered heterologous expression, that have inspired the isolation of new NPs and shown their potential application in the discovery of novel antibiotics. This review will address the discovery of antibiotics from actinomycetes from two different perspectives including: (1) an update of the most important antibiotics that have only reached the clinical development in the recent years despite their early discovery, and (2) an overview of the most recent classes of antibiotics described from 2006 to 2017 in the framework of the different strategies employed to untap novel compounds previously overlooked with traditional approaches.
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Affiliation(s)
- Olga Genilloud
- Fundación MEDINA, Avda Conocimiento 34, 18016 Granada, Spain.
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Singh SB, Xu L, Meinke PT, Kurepina N, Kreiswirth BN, Olsen DB, Young K. Thiazomycin, nocathiacin and analogs show strong activity against clinical strains of drug-resistant Mycobacterium tuberculosis. J Antibiot (Tokyo) 2017; 70:671-674. [DOI: 10.1038/ja.2016.165] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 11/21/2016] [Accepted: 12/07/2016] [Indexed: 11/10/2022]
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13
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Hwang HJ, Ciufolini MA. A route to the heterocyclic cluster of the E-series of thiopeptide antibiotics. J Org Chem 2015; 80:4184-8. [PMID: 25836570 DOI: 10.1021/acs.joc.5b00315] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A concise route to the 3-hydroxypyridine core of thiopeptide antibiotics such as nocathiacin is described. Key phases of the sequence involve a modified Hantzsch pyridine construction and a chemoselective Peng deprotection of a phenolic MOM ether.
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Affiliation(s)
- Hee-Jong Hwang
- Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | - Marco A Ciufolini
- Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
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14
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Abstract
Transfer RNAs (tRNAs) are central players in the protein translation machinery and as such are prominent targets for a large number of natural and synthetic antibiotics. This review focuses on the role of tRNAs in bacterial antibiosis. We will discuss examples of antibiotics that target multiple stages in tRNA biology from tRNA biogenesis and modification, mature tRNAs, aminoacylation of tRNA as well as prevention of proper tRNA function by small molecules binding to the ribosome. Finally, the role of deacylated tRNAs in the bacterial “stringent response” mechanism that can lead to bacteria displaying antibiotic persistence phenotypes will be discussed.
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15
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Structural basis and dynamics of multidrug recognition in a minimal bacterial multidrug resistance system. Proc Natl Acad Sci U S A 2014; 111:E5498-507. [PMID: 25489067 DOI: 10.1073/pnas.1412070111] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
TipA is a transcriptional regulator found in diverse bacteria. It constitutes a minimal autoregulated multidrug resistance system against numerous thiopeptide antibiotics. Here we report the structures of its drug-binding domain TipAS in complexes with promothiocin A and nosiheptide, and a model of the thiostrepton complex. Drug binding induces a large transition from a partially unfolded to a globin-like structure. The structures rationalize the mechanism of promiscuous, yet specific, drug recognition: (i) a four-ring motif present in all known TipA-inducing antibiotics is recognized specifically by conserved TipAS amino acids; and (ii) the variable part of the antibiotic is accommodated within a flexible cleft that rigidifies upon drug binding. Remarkably, the identified four-ring motif is also the major interacting part of the antibiotic with the ribosome. Hence the TipA multidrug resistance mechanism is directed against the same chemical motif that inhibits protein synthesis. The observed identity of chemical motifs responsible for antibiotic function and resistance may be a general principle and could help to better define new leads for antibiotics.
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16
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Rani R, Granchi C. Bioactive heterocycles containing endocyclic N-hydroxy groups. Eur J Med Chem 2014; 97:505-24. [PMID: 25466924 DOI: 10.1016/j.ejmech.2014.11.031] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 11/13/2014] [Accepted: 11/15/2014] [Indexed: 10/24/2022]
Abstract
Drug-likeness rules consider N-O single bonds as "structural alerts" which should not be present in a perspective drug candidate. In most cases this concern is correct, since it is known that N-hydroxy metabolites of branded drugs produce reactive species that cause serious side effects. However, this dangerous reactivity of the N-OH species generally takes place when the nitrogen atom is not comprised in a cyclic moiety. In fact, the same type of metabolic behavior should not be expected when the nitrogen atom is included in the ring of an aromatic heterocyclic scaffold. Nevertheless, heterocycles bearing endocyclic N-hydroxy portions have so far been poorly studied as chemical classes that may provide new therapeutic agents. This review provides an overview of N-OH-containing heterocycles with reported bioactivities that may be considered as therapeutically relevant and, therefore, may extend the chemical space available for the future development of novel pharmaceuticals. A systematic treatment of the various chemical classes belonging to this particular family of molecules is described along with a discussion of the biological activities associated to the most important examples.
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Affiliation(s)
- Reshma Rani
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno 6, 56126 Pisa, Italy
| | - Carlotta Granchi
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno 6, 56126 Pisa, Italy.
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17
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Abstract
This paper highlights ongoing efforts toward Erythrina alkaloids, himandrine, tetrodotoxin, and thiopeptide antibiotics such as nosiheptide and describes representative spinoffs in biomedicine that emanated from the author’s research in synthetic organic chemistry.
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Affiliation(s)
- Marco A. Ciufolini
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
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18
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Thiopeptide antibiotics: retrospective and recent advances. Mar Drugs 2014; 12:317-51. [PMID: 24445304 PMCID: PMC3917276 DOI: 10.3390/md12010317] [Citation(s) in RCA: 129] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 12/13/2013] [Accepted: 12/16/2013] [Indexed: 02/06/2023] Open
Abstract
Thiopeptides, or thiazolyl peptides, are a relatively new family of antibiotics that already counts with more than one hundred different entities. Although they are mainly isolated from soil bacteria, during the last decade, new members have been isolated from marine samples. Far from being limited to their innate antibacterial activity, thiopeptides have been found to possess a wide range of biological properties, including anticancer, antiplasmodial, immunosuppressive, etc. In spite of their ribosomal origin, these highly posttranslationally processed peptides have posed a fascinating synthetic challenge, prompting the development of various methodologies and strategies. Regardless of their limited solubility, intensive investigations are bringing thiopeptide derivatives closer to the clinic, where they are likely to show their veritable therapeutic potential.
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Singh SB, Young K, Miesel L. Screening strategies for discovery of antibacterial natural products. Expert Rev Anti Infect Ther 2013; 9:589-613. [PMID: 21819327 DOI: 10.1586/eri.11.81] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Microbial-derived natural products have been a traditional source of antibiotics and antibiotic leads and continue to be effective sources of antibiotics today. The most important of these discoveries were made about 50 years ago. Chemical modifications of natural products discovered during those years continue to produce new clinical agents but their value is now, unfortunately, fading away owing to the exhaustion of opportunities of chemical modifications. The discovery of new natural antibiotics is directly linked to new screening technologies, particularly technologies that can help to eliminate the rediscovery of known antibiotics. In this article, we have reviewed the screening technologies from recent literature as well as originating from authors laboratories that were used for the screening of natural products. The article covers the entire spectrum of screening strategies, including classical empiric whole-cell assays to more sophisticated antisense based hypersensitive Staphylococcus aureus Fitness Test assays designed to screen all targets simultaneously. These technologies have led to the discovery of a series of natural product antibiotics, which have been summarized, including the discovery of platensimycin, platencin, nocathiacins, philipimycin, cyclothialidine and muryamycins. It is quite clear that natural products provide a tremendous opportunity to discover new antibiotics when combined with new hyper-sensitive whole-cell technologies.
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Affiliation(s)
- Sheo B Singh
- Merck Research Laboratories, Rahway, NJ 07065, USA.
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Occurrence, distribution, dereplication and efficient discovery of thiazolyl peptides by sensitive-resistant pair screening. J Antibiot (Tokyo) 2013; 66:599-607. [DOI: 10.1038/ja.2013.54] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 04/16/2013] [Accepted: 04/25/2013] [Indexed: 11/08/2022]
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Abstract
Solutions are urgently required for the growing number of infections caused by antibiotic-resistant bacteria. Bacteriocins, which are antimicrobial peptides produced by certain bacteria, might warrant serious consideration as alternatives to traditional antibiotics. These molecules exhibit significant potency against other bacteria (including antibiotic-resistant strains), are stable and can have narrow or broad activity spectra. Bacteriocins can even be produced in situ in the gut by probiotic bacteria to combat intestinal infections. Although the application of specific bacteriocins might be curtailed by the development of resistance, an understanding of the mechanisms by which such resistance could emerge will enable researchers to develop strategies to minimize this potential problem.
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Affiliation(s)
- Paul D Cotter
- Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland.
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Kai M, González I, Genilloud O, Singh SB, Svatoš A. Direct mass spectrometric screening of antibiotics from bacterial surfaces using liquid extraction surface analysis. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2012; 26:2477-82. [PMID: 22976215 DOI: 10.1002/rcm.6365] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
RATIONALE There is a need to find new antibiotic agents to fight resistant pathogenic bacteria. To search successfully for novel antibiotics from bacteria cultivated under diverse conditions, we need a fast and cost-effective screening method. METHODS A combination of Liquid Extraction Surface Analysis (LESA), automated chip-based nanoelectrospray ionization, and high-resolution mass or tandem mass spectrometry using an Orbitrap XL was tested as the screening platform. Actinobacteria, known to produce well-recognized thiazolyl peptide antibiotics, were cultivated on a plate of solid medium and the antibiotics were extracted by organic solvent mixtures from the surface of colonies grown on the plate and analyzed using mass spectrometry (MS). RESULTS LESA combined with high-resolution MS is a powerful tool with which to extract and detect thiazolyl peptide antibiotics from different Actinobacteria. Known antibiotics were correctly detected with high mass accuracy (<4 ppm) and structurally characterized using tandem mass spectra. Our method is the first step toward the development of a novel high-throughput extraction and identification tool for antibiotics in particular and natural products in general. CONCLUSIONS The method described in this paper is suitable for (1) screening the natural products produced by bacterial colonies on cultivation plates within the first 2 min following extraction and (2) detecting antibiotics at high mass accuracy; the cost is around 2 Euro per sample.
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Affiliation(s)
- Marco Kai
- Research Group Mass Spectrometry, Max Planck Institute for Chemical Ecology, Jena, Germany
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YUAN GJ, LI PB, YANG H, WU XY, TU GQ, WEI SJ. Chemical screening of sixty-one actinomycete strains and anti-methicillin-resistant Staphylococcus aureus assays of target strains. Chin J Nat Med 2012. [DOI: 10.3724/sp.j.1009.2012.00155] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Ling Y, Wang X, Wang H, Yu J, Tang J, Wang D, Chen G, Huang J, Li Y, Zheng H. Design, synthesis, and antibacterial activity of novel pleuromutilin derivatives bearing an amino thiazolyl ring. Arch Pharm (Weinheim) 2012; 345:638-46. [PMID: 22532317 DOI: 10.1002/ardp.201100430] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2011] [Revised: 02/26/2012] [Accepted: 02/29/2012] [Indexed: 11/08/2022]
Abstract
A series of novel pleuromutilin derivatives containing the amino thiazolyl ring were designed, synthesized, and evaluated for their antibacterial activities in vitro against Gram-positive clinical bacteria. All the target compounds showed better aqueous solubility compared with the lead compound (10). Most compounds displayed strong antibacterial activities against both susceptible and resistant bacteria, particularly for the compound (12f) which showed extraordinary antibacterial properties superior to amoxicillin and tiamulin. Molecular docking studies revealed that the amino thiazolyl ring, the side chains of the pleuromutilin derivatives, can be adopted in the binding pocket of the 50S ribosomal subunit near the mutilin core. Therefore, our novel findings may provide new insights into the design of novel pleuromutilin derivatives and lay the basis for further studies on these promising antibiotics for human clinical use.
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Affiliation(s)
- Yong Ling
- Department of Pharmacy, School of Medical, Nantong University, Nantong, P. R. China
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Abstract
AbstractSecondary metabolites obtained from Actinomycetales provide a potential source of many novel compounds with antibacterial, antitumour, antifungal, antiviral, antiparasitic and other properties. The majority of these compounds are widely used as medicines for combating multidrug-resistant Gram-positive and Gram-negative bacterial strains. Members of the genus Streptomyces are profile producers of previously-known secondary metabolites. Actinomycetes have been isolated from terrestrial soils, from the rhizospheres of plant roots, and recently from marine sediments. This review demonstrates the diversity of secondary metabolites produced by actinomycete strains with respect to their chemical structure, biological activity and origin. On the basis of this diversity, this review concludes that the discovery of new bioactive compounds will continue to pose a great challenge for scientists.
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Coelomycin, a highly substituted 2,6-dioxo-pyrazine fungal metabolite antibacterial agent discovered by Staphylococcus aureus fitness test profiling. J Antibiot (Tokyo) 2010; 63:512-8. [DOI: 10.1038/ja.2010.86] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Antibiotic discovery in the twenty-first century: current trends and future perspectives. J Antibiot (Tokyo) 2010; 63:423-30. [PMID: 20551985 DOI: 10.1038/ja.2010.62] [Citation(s) in RCA: 158] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
New antibiotics are necessary to treat microbial pathogens that are becoming increasingly resistant to available treatment. Despite the medical need, the number of newly approved drugs continues to decline. We offer an overview of the pipeline for new antibiotics at different stages, from compounds in clinical development to newly discovered chemical classes. Consistent with historical data, the majority of antibiotics under clinical development are natural products or derivatives thereof. However, many of them also represent improved variants of marketed compounds, with the consequent risk of being only partially effective against the prevailing resistance mechanisms. In the discovery arena, instead, compounds with promising activities have been obtained from microbial sources and from chemical modification of antibiotic classes other than those in clinical use. Furthermore, new natural product scaffolds have also been discovered by ingenious screening programs. After providing selected examples, we offer our view on the future of antibiotic discovery.
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Baumann S, Schoof S, Bolten M, Haering C, Takagi M, Shin-ya K, Arndt HD. Molecular Determinants of Microbial Resistance to Thiopeptide Antibiotics. J Am Chem Soc 2010; 132:6973-81. [DOI: 10.1021/ja909317n] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sascha Baumann
- Fakultät Chemie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, D-44221 Dortmund, Germany, Max-Planck-Institut für Molekulare Physiologie, Otto-Hahn-Strasse 11, D-44227 Dortmund, Germany, and Biomedicinal Information Research Center (BIRC), 2-4-7 Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Sebastian Schoof
- Fakultät Chemie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, D-44221 Dortmund, Germany, Max-Planck-Institut für Molekulare Physiologie, Otto-Hahn-Strasse 11, D-44227 Dortmund, Germany, and Biomedicinal Information Research Center (BIRC), 2-4-7 Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Marcel Bolten
- Fakultät Chemie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, D-44221 Dortmund, Germany, Max-Planck-Institut für Molekulare Physiologie, Otto-Hahn-Strasse 11, D-44227 Dortmund, Germany, and Biomedicinal Information Research Center (BIRC), 2-4-7 Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Claudia Haering
- Fakultät Chemie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, D-44221 Dortmund, Germany, Max-Planck-Institut für Molekulare Physiologie, Otto-Hahn-Strasse 11, D-44227 Dortmund, Germany, and Biomedicinal Information Research Center (BIRC), 2-4-7 Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Motoki Takagi
- Fakultät Chemie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, D-44221 Dortmund, Germany, Max-Planck-Institut für Molekulare Physiologie, Otto-Hahn-Strasse 11, D-44227 Dortmund, Germany, and Biomedicinal Information Research Center (BIRC), 2-4-7 Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Kazuo Shin-ya
- Fakultät Chemie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, D-44221 Dortmund, Germany, Max-Planck-Institut für Molekulare Physiologie, Otto-Hahn-Strasse 11, D-44227 Dortmund, Germany, and Biomedicinal Information Research Center (BIRC), 2-4-7 Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Hans-Dieter Arndt
- Fakultät Chemie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, D-44221 Dortmund, Germany, Max-Planck-Institut für Molekulare Physiologie, Otto-Hahn-Strasse 11, D-44227 Dortmund, Germany, and Biomedicinal Information Research Center (BIRC), 2-4-7 Aomi, Koto-ku, Tokyo 135-0064, Japan
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Zhang C, Herath K, Jayasuriya H, Ondeyka JG, Zink DL, Occi J, Birdsall G, Venugopal J, Ushio M, Burgess B, Masurekar P, Barrett JF, Singh SB. Thiazomycins, thiazolyl peptide antibiotics from Amycolatopsis fastidiosa. JOURNAL OF NATURAL PRODUCTS 2009; 72:841-847. [PMID: 19334707 DOI: 10.1021/np800783b] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Thiazolyl peptides are a class of highly rigid trimacrocyclic compounds consisting of varying but large numbers of thiazole rings. The need for new antibacterial agents to treat infections caused by resistant bacteria prompted a reinvestigation of this class, leading to the previous isolation of thiazolyl peptides, namely, thiazomycin (5) and thiazomycin A (6), congeners of nocathiacins (1-4). Continued chemical screening led to the isolation of six new thiazolyl peptide congeners (8-13), of which three had truncated structures lacking an indole residue. From these, compound 8 showed activity similar to thiazomycin. Two compounds (9 and 10) showed intermediate activities, and the three truncated compounds (11-13) were essentially inactive. The discovery of the truncated compounds revealed the minimal structural requirements for activity and suggested probable biosynthetic pathways for more advanced compounds. The isolation, structure elucidation, antibacterial activity, and proposed biogenesis of thiazomycins are herein described.
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Affiliation(s)
- Chaowei Zhang
- Natural Products Chemistry, Merck Research Laboratories, 126 E Lincoln Avenue, Rahway, New Jersey 07065, USA
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Actinomycetes scale-up for the production of the antibacterial, nocathiacin. Biotechnol Prog 2009; 25:176-88. [DOI: 10.1002/btpr.122] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Zhang C, Zink DL, Ushio M, Burgess B, Onishi R, Masurekar P, Barrett JF, Singh SB. Isolation, structure, and antibacterial activity of thiazomycin A, a potent thiazolyl peptide antibiotic from Amycolatopsis fastidiosa. Bioorg Med Chem 2008; 16:8818-23. [PMID: 18804380 DOI: 10.1016/j.bmc.2008.08.079] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Revised: 08/26/2008] [Accepted: 08/29/2008] [Indexed: 10/21/2022]
Abstract
Thiazolyl peptides are a class of thiazole-rich macrocyclic potent antibacterial agents. Recently, we described thiazomycin, a new member of thiazolyl peptides, discovered by a thiazolyl peptide specific chemical screening. This method also allowed for the discovery of a new thiazolyl peptide, thiazomycin A, which carries modification in the oxazolidine ring of the amino sugar moiety. Thiazomycin A is a specific inhibitor of protein synthesis (IC(50) 0.7 microg/mL) and a potent Gram-positive antibacterial agent with minimum inhibitory concentration (MIC) ranging 0.002-0.25 microg/mL. The isolation and structure elucidation and biological activities of thiazomycin A are described.
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Zhang C, Occi J, Masurekar P, Barrett JF, Zink DL, Smith S, Onishi R, Ha S, Salazar O, Genilloud O, Basilio A, Vicente F, Gill C, Hickey EJ, Dorso K, Motyl M, Singh SB. Isolation, structure, and antibacterial activity of philipimycin, a thiazolyl peptide discovered from Actinoplanes philippinensis MA7347. J Am Chem Soc 2008; 130:12102-10. [PMID: 18698773 DOI: 10.1021/ja803183u] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Bacterial resistance to antibiotics, particularly to multiple drug resistant antibiotics, is becoming cause for significant concern. The only really viable course of action is to discover new antibiotics with novel mode of actions. Thiazolyl peptides are a class of natural products that are architecturally complex potent antibiotics but generally suffer from poor solubility and pharmaceutical properties. To discover new thiazolyl peptides potentially with better desired properties, we designed a highly specific assay with a pair of thiazomycin sensitive and resistant strains of Staphylococcus aureus, which led to the discovery of philipimycin, a new thiazolyl peptide glycoside. It was isolated along with an acid-catalyzed degradation product by bioassay-guided fractionation. Structure of both compounds was elucidated by extensive application of 2D NMR, 1D TOCSY, and HRESIFT-MS/MS. Both compounds showed strong antibacterial activities against gram-positive bacteria including MRSA and exhibited MIC values ranging from 0.015 to 1 microg/mL. Philipimycin was significantly more potent than the degradation product. Both compounds showed selective inhibition of protein synthesis, indicating that they targeted the ribosome. Philipimycin was effective in vivo in a mouse model of S. aureus infection exhibiting an ED50 value of 8.4 mg/kg. The docking studies of philipimycin suggested that a part of the molecule interacts with the ribosome and another part with Pro23, Pro22, and Pro26 of L11 protein, which helped in explaining the differential of activities between the sensitive and resistant strains. The design and execution of the bioassay, the isolation, structure, in vitro and in vivo antibacterial activity, and docking studies of philipimycin and its degradation product are described.
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Affiliation(s)
- Chaowei Zhang
- Merck Research Laboratories, Rahway, New Jersey 07065, USA
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Isolation and structure elucidation of thiazomycin- a potent thiazolyl peptide antibiotic from Amycolatopsis fastidiosa. J Antibiot (Tokyo) 2008; 60:554-64. [PMID: 17917238 DOI: 10.1038/ja.2007.70] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Thiazolyl peptides are a class of rigid macrocyclic compounds richly populated with thiazole rings. They are highly potent antibiotics but none have been advanced to clinic due to poor aqueous solubility. Recent progress in this field prompted a reinvestigation leading to the isolation of a new thiazolyl peptide, thiazomycin, a congener of nocathiacins. Thiazomycin possesses an oxazolidine ring as part of the amino-sugar moiety in contrast to the dimethyl amino group present in nocathiacin I. The presence of the oxazolidine ring provides additional opportunities for chemical modifications that are not possible with other nocathiacins. Thiazomycin is extremely potent against Gram-positive bacteria both in vitro and in vivo. The titer of thiazomycin in the fermentation broth was very low compared to the nocathiacins I and III. The lower titer together with its sandwiched order of elution presented significant challenges in large scale purification of thiazomycin. This problem was resolved by the development of an innovative preferential protonation based one- and/or two-step chromatographic method, which was used for pilot plant scale purifications of thiazomycin. The isolation and structure elucidation of thiazomycin is herein described.
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