101
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Myronovskyi M, Luzhetskyy A. Native and engineered promoters in natural product discovery. Nat Prod Rep 2016; 33:1006-19. [DOI: 10.1039/c6np00002a] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Transcriptional activation of biosynthetic gene clusters.
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Affiliation(s)
- Maksym Myronovskyi
- Helmholtz-Institute for Pharmaceutical Research Saarland
- 66123 Saarbrücken
- Germany
| | - Andriy Luzhetskyy
- Helmholtz-Institute for Pharmaceutical Research Saarland
- 66123 Saarbrücken
- Germany
- Department of Pharmaceutical Biotechnology
- Saarland University
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102
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Weissman KJ. Genetic engineering of modular PKSs: from combinatorial biosynthesis to synthetic biology. Nat Prod Rep 2016; 33:203-30. [DOI: 10.1039/c5np00109a] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
This reviews covers on-going efforts at engineering the gigantic modular polyketide synthases (PKSs), highlighting both notable successes and failures.
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Affiliation(s)
- Kira J. Weissman
- UMR 7365
- Ingénierie Moléculaire et Physiopathologie Articulaire (IMoPA)
- CNRS-Université de Lorraine
- Biopôle de l'Université de Lorraine
- 54505 Vandœuvre-lès-Nancy Cedex
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103
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Rao HCY, Rakshith D, Satish S. Antimicrobial properties of endophytic actinomycetes isolated from Combretum latifolium Blume, a medicinal shrub from Western Ghats of India. ACTA ACUST UNITED AC 2015. [DOI: 10.1007/s11515-015-1377-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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104
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Fayed B, Ashford DA, Hashem AM, Amin MA, El Gazayerly ON, Gregory MA, Smith MCM. Multiplexed integrating plasmids for engineering of the erythromycin gene cluster for expression in Streptomyces spp. and combinatorial biosynthesis. Appl Environ Microbiol 2015; 81:8402-13. [PMID: 26431970 PMCID: PMC4644662 DOI: 10.1128/aem.02403-15] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Accepted: 09/25/2015] [Indexed: 01/11/2023] Open
Abstract
Bacteria in the genus Streptomyces and its close relatives are prolific producers of secondary metabolites with antibiotic activity. Genome sequencing of these bacteria has revealed a rich source of potentially new antibiotic pathways, whose products have never been observed. Moreover, these new pathways can provide novel genes that could be used in combinatorial biosynthesis approaches to generate unnatural analogues of existing antibiotics. We explore here the use of multiple orthologous integrating plasmid systems, based on the int/attP loci from phages TG1, SV1, and ϕBT1, to express the polyketide synthase (PKS) for erythromycin in a heterologous Streptomyces host. Streptomyces strains containing the three polyketide synthase genes eryAI, eryAII, and eryAIII expressed from three different integrated plasmids produced the aglycone intermediate, 6-deoxyerythronolide B (6-dEB). A further pair of integrating plasmids, both derived from the ϕC31 int/attP locus, were constructed carrying a gene cassette for glycosylation of the aglycone intermediates, with or without the tailoring gene, eryF, required for the synthesis of erythronolide B (EB). Liquid chromatography-mass spectrometry of the metabolites indicated the production of angolosaminyl-6-dEB and angolosaminyl-EB. The advantages of using multiplexed integrating plasmids for engineering expression and for combinatorial biosynthesis were demonstrated.
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Affiliation(s)
- Bahgat Fayed
- Department of Biology, University of York, York, United Kingdom Chemistry of Natural and Microbial Products Department, National Research Centre, Cairo, Egypt
| | - David A Ashford
- Bioscience Technology Facility, Department of Biology, University of York, York, United Kingdom
| | - Amal M Hashem
- Chemistry of Natural and Microbial Products Department, National Research Centre, Cairo, Egypt
| | - Magdy A Amin
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Omaima N El Gazayerly
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Matthew A Gregory
- Isomerase Therapeutics, Science Village, Chesterford Research Park, Cambridge, United Kingdom
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105
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Luo Y, Zhang L, Barton KW, Zhao H. Systematic Identification of a Panel of Strong Constitutive Promoters from Streptomyces albus. ACS Synth Biol 2015; 4:1001-10. [PMID: 25924180 DOI: 10.1021/acssynbio.5b00016] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Actinomycetes are important organisms for the biosynthesis of valuable natural products. However, only a limited number of well-characterized native constitutive promoters from actinomycetes are available for the construction and engineering of large biochemical pathways. Here, we report the discovery and characterization of 32 candidate promoters identified from Streptomyces albus J1074 by RNA-seq analysis. These 32 promoters were cloned and characterized using a streptomycete reporter gene, xylE, encoding catechol 2,3-dioxygenase. The strengths of the identified strong promoters varied from 200 to 1300% of the strength of the well-known ermE*p in MYG medium, and the strongest of these promoters was by far the strongest actinomycete promoter ever reported in the literature. To further confirm the strengths of these promoters, qPCR was employed to determine the transcriptional levels of the xylE reporter. In total, 10 strong promoters were identified and four constitutive promoters were characterized via a time-course study. These promoters were used in a plug-and-play platform to activate a cryptic gene cluster from Streptomyces griseus, and successful activation of the target pathway was observed in three widely used Streptomyces strains. Therefore, these promoters should be highly useful in current synthetic biology platforms for activation and characterization of silent natural product biosynthetic pathways as well as the optimization of pathways for the synthesis of important natural products in actinomycetes.
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Affiliation(s)
- Yunzi Luo
- Institute
for Genomic Biology, University of Illinois at Urbana−Champaign, 1206 West Gregory Drive, Urbana, Illinois 61801, United States,
| | | | | | - Huimin Zhao
- Institute
for Genomic Biology, University of Illinois at Urbana−Champaign, 1206 West Gregory Drive, Urbana, Illinois 61801, United States,
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106
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Nah HJ, Woo MW, Choi SS, Kim ES. Precise cloning and tandem integration of large polyketide biosynthetic gene cluster using Streptomyces artificial chromosome system. Microb Cell Fact 2015; 14:140. [PMID: 26377404 PMCID: PMC4573296 DOI: 10.1186/s12934-015-0325-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 08/27/2015] [Indexed: 11/29/2022] Open
Abstract
Background Direct cloning combined with heterologous expression of a secondary metabolite biosynthetic gene cluster has become a useful strategy for production improvement and pathway modification of potentially valuable natural products present at minute quantities in original isolates of actinomycetes. However, precise cloning and efficient overexpression of an entire biosynthetic gene cluster remains challenging due to the ineffectiveness of current genetic systems in manipulating large-sized gene clusters for heterologous as well as homologous expression. Results A versatile Escherichia coli-Streptomyces shuttle bacterial artificial chromosomal (BAC) conjugation vector, pSBAC, was used along with a cluster tandem integration approach to carry out homologous and heterologous overexpression of a large 80-kb polyketide biosynthetic pathway gene cluster of tautomycetin (TMC), which is a protein phosphatase PP1/PP2A inhibitor and T cell-specific immunosuppressant. Unique XbaI restriction sites were precisely inserted at both border regions of the TMC biosynthetic gene cluster within the chromosome of TMC-producing Streptomyces sp. CK4412, followed by site-specific recombination of pSBAC into the flanking region of the TMC gene cluster. The entire TMC gene cluster was then rescued as a single giant recombinant pSBAC by XbaI digestion of the chromosomal DNA as well as subsequent self-ligation. Next, the recombinant pSBAC construct containing the entire TMC cluster in E. coli was directly conjugated into model Streptomyces strains, resulting in rapid and enhanced TMC production. Moreover, introduction of the TMC cluster-containing pSBAC into wild-type Streptomyces sp. CK4412 as well as a recombinant S. coelicolor strain resulted in a chromosomal tandem repeat of the entire TMC cluster with 14-fold and 5.4-fold enhanced TMC productivities, respectively. Conclusions The 80-kb TMC biosynthetic gene cluster was isolated in a single integration vector, pSBAC. Introduction of TMC biosynthetic gene cluster in TMC non-producing strains has resulted in similar amount of TMC production yield. Moreover, over-expression of TMC biosynthetic gene cluster in original producing strain and recombinant S. coelicolor dramatically increased TMC production. Thus, this strategy can be employed to develop a custom overexpression scheme of entire metabolite pathway clusters present in actinomycetes. Electronic supplementary material The online version of this article (doi:10.1186/s12934-015-0325-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hee-Ju Nah
- Department of Biological Engineering, Inha University, Incheon, 402-751, Korea.
| | - Min-Woo Woo
- Department of Biological Engineering, Inha University, Incheon, 402-751, Korea.
| | - Si-Sun Choi
- Department of Biological Engineering, Inha University, Incheon, 402-751, Korea.
| | - Eung-Soo Kim
- Department of Biological Engineering, Inha University, Incheon, 402-751, Korea.
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107
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A Streptomyces coelicolor host for the heterologous expression of Type III polyketide synthase genes. Microb Cell Fact 2015; 14:145. [PMID: 26376792 PMCID: PMC4573997 DOI: 10.1186/s12934-015-0335-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Accepted: 09/03/2015] [Indexed: 11/30/2022] Open
Abstract
Background Recent advances in genome sequencing, combined with bioinformatic analysis, has led to the identification of numerous novel natural product gene clusters, particularly in actinomycetes of terrestrial and marine origin. Many of these gene clusters encode uncharacterised Type III polyketide synthases. To facilitate the study of these genes and their potentially novel products, we set out to construct an actinomycete expression host specifically designed for the heterologous expression of Type III PKS genes and their gene clusters. Results A derivative of Streptomyces coelicolor A3(2) designed for the expression of Type III polyketide synthase (PKS) genes was constructed from the previously engineered expression strain S. coelicolor M1152 [Δact Δred Δcpk Δcda rpoB(C1298T)] by removal of all three of the endogenous Type III PKS genes (gcs,srsA,rppA) by PCR targeting. The resulting septuple deletion mutant, M1317, proved to be an effective surrogate host for the expression of actinobacterial Type III PKS genes: expression of the reintroduced gcs gene from S. coelicolor and of the heterologous rppA gene from Streptomyces venezuelae under the control of the constitutive ermE* promoter resulted in copious production of germicidin and flaviolin, respectively. Conclusions The newly constructed expression host S. coelicolor M1317 should be particularly useful for the discovery and analysis of new Type III polyketide metabolites.
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108
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Genetic manipulation of secondary metabolite biosynthesis for improved production in Streptomyces and other actinomycetes. J Ind Microbiol Biotechnol 2015; 43:343-70. [PMID: 26364200 DOI: 10.1007/s10295-015-1682-x] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 08/28/2015] [Indexed: 12/18/2022]
Abstract
Actinomycetes continue to be important sources for the discovery of secondary metabolites for applications in human medicine, animal health, and crop protection. With the maturation of actinomycete genome mining as a robust approach to identify new and novel cryptic secondary metabolite gene clusters, it is critical to continue developing methods to activate and enhance secondary metabolite biosynthesis for discovery, development, and large-scale manufacturing. This review covers recent reports on promising new approaches and further validations or technical improvements of existing approaches to strain improvement applicable to a wide range of Streptomyces species and other actinomycetes.
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109
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Metabolic profiling as a tool for prioritizing antimicrobial compounds. J Ind Microbiol Biotechnol 2015; 43:299-312. [PMID: 26335567 PMCID: PMC4752588 DOI: 10.1007/s10295-015-1666-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Accepted: 07/25/2015] [Indexed: 11/29/2022]
Abstract
Metabolomics is an analytical technique that allows scientists to globally profile low molecular weight metabolites between samples in a medium- or high-throughput environment. Different biological samples are statistically analyzed and correlated to a bioactivity of interest, highlighting differentially produced compounds as potential biomarkers. Here, we review NMR- and MS-based metabolomics as technologies to facilitate the identification of novel antimicrobial natural products from microbial sources. Approaches to elicit the production of poorly expressed (cryptic) molecules are thereby a key to allow statistical analysis of samples to identify bioactive markers, while connection of compounds to their biosynthetic gene cluster is a determining step in elucidating the biosynthetic pathway and allows downstream process optimization and upscaling. The review focuses on approaches built around NMR-based metabolomics, which enables efficient dereplication and guided fractionation of (antimicrobial) compounds.
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110
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Fedorenko V, Genilloud O, Horbal L, Marcone GL, Marinelli F, Paitan Y, Ron EZ. Antibacterial Discovery and Development: From Gene to Product and Back. BIOMED RESEARCH INTERNATIONAL 2015; 2015:591349. [PMID: 26339625 PMCID: PMC4538407 DOI: 10.1155/2015/591349] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 12/30/2014] [Accepted: 01/13/2015] [Indexed: 12/23/2022]
Abstract
Concern over the reports of antibiotic-resistant bacterial infections in hospitals and in the community has been publicized in the media, accompanied by comments on the risk that we may soon run out of antibiotics as a way to control infectious disease. Infections caused by Enterococcus faecium, Staphylococcus aureus, Klebsiella species, Clostridium difficile, Acinetobacter baumannii, Pseudomonas aeruginosa, Escherichia coli, and other Enterobacteriaceae species represent a major public health burden. Despite the pharmaceutical sector's lack of interest in the topic in the last decade, microbial natural products continue to represent one of the most interesting sources for discovering and developing novel antibacterials. Research in microbial natural product screening and development is currently benefiting from progress that has been made in other related fields (microbial ecology, analytical chemistry, genomics, molecular biology, and synthetic biology). In this paper, we review how novel and classical approaches can be integrated in the current processes for microbial product screening, fermentation, and strain improvement.
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Affiliation(s)
- Victor Fedorenko
- Department of Genetics and Biotechnology, Ivan Franko National University of Lviv, Lviv 79005, Ukraine
| | - Olga Genilloud
- Fundación MEDINA, Health Sciences Technology Park, 18016 Granada, Spain
| | - Liliya Horbal
- Department of Genetics and Biotechnology, Ivan Franko National University of Lviv, Lviv 79005, Ukraine
| | - Giorgia Letizia Marcone
- Department of Biotechnology and Life Sciences, University of Insubria, 21100 Varese, Italy
- The Protein Factory, Interuniversity Centre Politecnico di Milano, ICRM CNR Milano, and University of Insubria, 21100 Varese, Italy
| | - Flavia Marinelli
- Department of Biotechnology and Life Sciences, University of Insubria, 21100 Varese, Italy
- The Protein Factory, Interuniversity Centre Politecnico di Milano, ICRM CNR Milano, and University of Insubria, 21100 Varese, Italy
| | - Yossi Paitan
- Clinical Microbiology Laboratory, Meir Medical Center, 44281 Kfar Saba, Israel
| | - Eliora Z. Ron
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, 6997801 Tel Aviv, Israel
- Galilee Research Institute (MIGAL), 11016 Kiryat Shmona, Israel
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111
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Reen FJ, Romano S, Dobson ADW, O'Gara F. The Sound of Silence: Activating Silent Biosynthetic Gene Clusters in Marine Microorganisms. Mar Drugs 2015; 13:4754-83. [PMID: 26264003 PMCID: PMC4557003 DOI: 10.3390/md13084754] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 06/05/2015] [Accepted: 07/27/2015] [Indexed: 12/14/2022] Open
Abstract
Unlocking the rich harvest of marine microbial ecosystems has the potential to both safeguard the existence of our species for the future, while also presenting significant lifestyle benefits for commercial gain. However, while significant advances have been made in the field of marine biodiscovery, leading to the introduction of new classes of therapeutics for clinical medicine, cosmetics and industrial products, much of what this natural ecosystem has to offer is locked in, and essentially hidden from our screening methods. Releasing this silent potential represents a significant technological challenge, the key to which is a comprehensive understanding of what controls these systems. Heterologous expression systems have been successful in awakening a number of these cryptic marine biosynthetic gene clusters (BGCs). However, this approach is limited by the typically large size of the encoding sequences. More recently, focus has shifted to the regulatory proteins associated with each BGC, many of which are signal responsive raising the possibility of exogenous activation. Abundant among these are the LysR-type family of transcriptional regulators, which are known to control production of microbial aromatic systems. Although the environmental signals that activate these regulatory systems remain unknown, it offers the exciting possibility of evoking mimic molecules and synthetic expression systems to drive production of potentially novel natural products in microorganisms. Success in this field has the potential to provide a quantum leap forward in medical and industrial bio-product development. To achieve these new endpoints, it is clear that the integrated efforts of bioinformaticians and natural product chemists will be required as we strive to uncover new and potentially unique structures from silent or cryptic marine gene clusters.
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Affiliation(s)
- F Jerry Reen
- BIOMERIT Research Centre, School of Microbiology, University College Cork-National University of Ireland, Cork, Ireland.
| | - Stefano Romano
- BIOMERIT Research Centre, School of Microbiology, University College Cork-National University of Ireland, Cork, Ireland.
| | - Alan D W Dobson
- School of Microbiology, University College Cork-National University of Ireland, Cork, Ireland.
| | - Fergal O'Gara
- BIOMERIT Research Centre, School of Microbiology, University College Cork-National University of Ireland, Cork, Ireland.
- School of Biomedical Sciences, Curtin University, Perth WA 6845, Australia.
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112
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Bonet B, Teufel R, Crüsemann M, Ziemert N, Moore BS. Direct capture and heterologous expression of Salinispora natural product genes for the biosynthesis of enterocin. JOURNAL OF NATURAL PRODUCTS 2015; 78:539-42. [PMID: 25382643 PMCID: PMC4380194 DOI: 10.1021/np500664q] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Heterologous expression of secondary metabolic pathways is a promising approach for the discovery and characterization of bioactive natural products. Herein we report the first heterologous expression of a natural product from the model marine actinomycete genus Salinispora. Using the recently developed method of yeast-mediated transformation-associated recombination for natural product gene clusters, we captured a type II polyketide synthase pathway from Salinispora pacifica with high homology to the enterocin pathway from Streptomyces maritimus and successfully produced enterocin in two different Streptomyces host strains. This result paves the way for the systematic interrogation of Salinispora's promising secondary metabolome.
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Affiliation(s)
- Bailey Bonet
- Center
for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, La Jolla, California 92037, United States
| | - Robin Teufel
- Center
for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, La Jolla, California 92037, United States
| | - Max Crüsemann
- Center
for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, La Jolla, California 92037, United States
| | - Nadine Ziemert
- Center
for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, La Jolla, California 92037, United States
- E-mail:
| | - Bradley S. Moore
- Center
for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, La Jolla, California 92037, United States
- Skaggs
School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California 92093, United States
- E-mail:
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113
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Harvey AL, Edrada-Ebel R, Quinn RJ. The re-emergence of natural products for drug discovery in the genomics era. Nat Rev Drug Discov 2015; 14:111-29. [PMID: 25614221 DOI: 10.1038/nrd4510] [Citation(s) in RCA: 1515] [Impact Index Per Article: 168.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Natural products have been a rich source of compounds for drug discovery. However, their use has diminished in the past two decades, in part because of technical barriers to screening natural products in high-throughput assays against molecular targets. Here, we review strategies for natural product screening that harness the recent technical advances that have reduced these barriers. We also assess the use of genomic and metabolomic approaches to augment traditional methods of studying natural products, and highlight recent examples of natural products in antimicrobial drug discovery and as inhibitors of protein-protein interactions. The growing appreciation of functional assays and phenotypic screens may further contribute to a revival of interest in natural products for drug discovery.
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Affiliation(s)
- Alan L Harvey
- 1] Research and Innovation Support, Dublin City University, Dublin 9, Ireland. [2] Strathclyde Institute of Pharmacy and Biomedical Science, University of Strathclyde, Glasgow G4 0NR, UK
| | - RuAngelie Edrada-Ebel
- Strathclyde Institute of Pharmacy and Biomedical Science, University of Strathclyde, Glasgow G4 0NR, UK
| | - Ronald J Quinn
- Eskitis Institute for Drug Discovery, Griffith University, Brisbane, Queensland 4111, Australia
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114
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Zhou Z, Xu Q, Bu Q, Guo Y, Liu S, Liu Y, Du Y, Li Y. Genome mining-directed activation of a silent angucycline biosynthetic gene cluster in Streptomyces chattanoogensis. Chembiochem 2014; 16:496-502. [PMID: 25511454 DOI: 10.1002/cbic.201402577] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Indexed: 01/01/2023]
Abstract
Genomic sequencing of actinomycetes has revealed the presence of numerous gene clusters seemingly capable of natural product biosynthesis, yet most clusters are cryptic under laboratory conditions. Bioinformatics analysis of the completely sequenced genome of Streptomyces chattanoogensis L10 (CGMCC 2644) revealed a silent angucycline biosynthetic gene cluster. The overexpression of a pathway-specific activator gene under the constitutive ermE* promoter successfully triggered the expression of the angucycline biosynthetic genes. Two novel members of the angucycline antibiotic family, chattamycins A and B, were further isolated and elucidated. Biological activity assays demonstrated that chattamycin B possesses good antitumor activities against human cancer cell lines and moderate antibacterial activities. The results presented here provide a feasible method to activate silent angucycline biosynthetic gene clusters to discover potential new drug leads.
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Affiliation(s)
- Zhenxing Zhou
- Institute of Biochemistry, College of Life Sciences, Zhejiang University, Zijingang Campus, 388 Yuhangtang Road, Hangzhou 310058 (China)
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115
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Poust S, Hagen A, Katz L, Keasling JD. Narrowing the gap between the promise and reality of polyketide synthases as a synthetic biology platform. Curr Opin Biotechnol 2014; 30:32-9. [DOI: 10.1016/j.copbio.2014.04.011] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 04/09/2014] [Accepted: 04/11/2014] [Indexed: 11/27/2022]
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116
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Chen C, Zhao X, Jin Y, Zhao Z(K, Suh JW. Rapid construction of a Bacterial Artificial Chromosomal (BAC) expression vector using designer DNA fragments. Plasmid 2014; 76:79-86. [DOI: 10.1016/j.plasmid.2014.10.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 09/24/2014] [Accepted: 10/09/2014] [Indexed: 11/28/2022]
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117
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Duan X, Xiang X, Xie J. Crucial components of mycobacterium type II fatty acid biosynthesis (Fas-II) and their inhibitors. FEMS Microbiol Lett 2014; 360:87-99. [DOI: 10.1111/1574-6968.12597] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 09/09/2014] [Accepted: 09/11/2014] [Indexed: 01/27/2023] Open
Affiliation(s)
- Xiangke Duan
- Institute of Modern Biopharmaceuticals; State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area; Key Laboratory of Eco-Environments in Three Gorges Reservoir Region; Ministry of Education; School of Life Sciences; Southwest University; Beibei Chongqing China
| | - Xiaohong Xiang
- Institute of Modern Biopharmaceuticals; State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area; Key Laboratory of Eco-Environments in Three Gorges Reservoir Region; Ministry of Education; School of Life Sciences; Southwest University; Beibei Chongqing China
| | - Jianping Xie
- Institute of Modern Biopharmaceuticals; State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area; Key Laboratory of Eco-Environments in Three Gorges Reservoir Region; Ministry of Education; School of Life Sciences; Southwest University; Beibei Chongqing China
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118
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Baltz RH. Combinatorial biosynthesis of cyclic lipopeptide antibiotics: a model for synthetic biology to accelerate the evolution of secondary metabolite biosynthetic pathways. ACS Synth Biol 2014; 3:748-58. [PMID: 23654258 DOI: 10.1021/sb3000673] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Nonribosomal peptide synthetases (NRPSs) are giant multi-enzymes that carry out sequencial assembly line couplings of amino acids to generate linear or cyclic peptides. NRPSs are composed of repeating enzyme domains with modular organization to activate and couple specific amino acids in a particular order. From a synthetic biology perspective, they can be considered as peptide assembly machines composed of devices to couple fatty acids to l-amino acids, l-amino acids to l-amino acids, and d-amino acids to l-amino acids. The coupling devices are composed of specific parts that contain two or more enzyme domains that can be exchanged combinatorially to generate novel peptide assembly machines to produce novel peptides. The potent lipopeptide antibiotics daptomycin and A54145E have identical cyclic depsipeptide ring structures and stereochemistry but have divergent amino acid sequences. As their biosynthetic gene clusters are derived from an ancient ancestral lipopetide pathway, these lipopeptides provided an attractive model to develop combinatorial biosynthesis to generate antibiotics superior to daptomycin. These studies on combinatorial biosynthesis have helped generate guidelines for the successful assembly of NRPS parts and devices that can be used to generate novel lipopeptide structures and have established a basis for future synthetic biology studies to further develop combinatorial biosynthesis as a robust approach to natural product drug discovery.
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Affiliation(s)
- Richard H. Baltz
- CognoGen Biotechnology Consulting, 6438 North Olney Street, Indianapolis,
Indiana 46220, United States
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119
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Fair RJ, Tor Y. Antibiotics and bacterial resistance in the 21st century. PERSPECTIVES IN MEDICINAL CHEMISTRY 2014; 6:25-64. [PMID: 25232278 PMCID: PMC4159373 DOI: 10.4137/pmc.s14459] [Citation(s) in RCA: 854] [Impact Index Per Article: 85.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 06/24/2014] [Accepted: 06/24/2014] [Indexed: 12/11/2022]
Abstract
Dangerous, antibiotic resistant bacteria have been observed with increasing frequency over the past several decades. In this review the factors that have been linked to this phenomenon are addressed. Profiles of bacterial species that are deemed to be particularly concerning at the present time are illustrated. Factors including economic impact, intrinsic and acquired drug resistance, morbidity and mortality rates, and means of infection are taken into account. Synchronously with the waxing of bacterial resistance there has been waning antibiotic development. The approaches that scientists are employing in the pursuit of new antibacterial agents are briefly described. The standings of established antibiotic classes as well as potentially emerging classes are assessed with an emphasis on molecules that have been clinically approved or are in advanced stages of development. Historical perspectives, mechanisms of action and resistance, spectrum of activity, and preeminent members of each class are discussed.
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Affiliation(s)
- Richard J Fair
- Department for Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Berlin, Germany
| | - Yitzhak Tor
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
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120
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Luo Y, Huang H, Liang J, Wang M, Lu L, Shao Z, Cobb RE, Zhao H. Activation and characterization of a cryptic polycyclic tetramate macrolactam biosynthetic gene cluster. Nat Commun 2014; 4:2894. [PMID: 24305602 PMCID: PMC3969335 DOI: 10.1038/ncomms3894] [Citation(s) in RCA: 169] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 11/07/2013] [Indexed: 12/16/2022] Open
Abstract
Polycyclic tetramate macrolactams (PTMs) are a widely distributed class of natural products with important biological activities. However, many of them have not been characterized. Here we apply a plug and play synthetic biology strategy to activate a cryptic PTM biosynthetic gene cluster SGR810-815 from Streptomyces griseus and discover three potential PTMs. This gene cluster is highly conserved in phylogenetically diverse bacterial strains and contains an unusual hybrid polyketide synthase-nonribosomal peptide synthetase (PKS-NRPS) which resembles iterative PKSs known in fungi. To further characterize this gene cluster, we use the same synthetic biology approach to create a series of gene deletion constructs and elucidate the biosynthetic steps for the formation of the polycyclic system. The strategy we employ bypasses the traditional laborious processes to elicit gene cluster expression and should be generally applicable to many other silent or cryptic gene clusters for discovery and characterization of new natural products.
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Affiliation(s)
- Yunzi Luo
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA
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121
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Shao Z, Zhao H. Manipulating natural product biosynthetic pathways via DNA assembler. ACTA ACUST UNITED AC 2014; 6:65-100. [PMID: 24903884 DOI: 10.1002/9780470559277.ch130191] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
DNA assembler is an efficient synthetic biology method for constructing and manipulating biochemical pathways. The rapidly increasing number of sequenced genomes provides a rich source for discovery of gene clusters involved in synthesizing new natural products. However, both discovery and economical production are hampered by our limited knowledge in manipulating most organisms and the corresponding pathways. By taking advantage of yeast in vivo homologous recombination, DNA assembler synthesizes an entire expression vector containing the target biosynthetic pathway and the genetic elements needed for DNA maintenance and replication. Here we use the spectinabilin clusters originated from two hosts as examples to illustrate the guidelines of using DNA assembler for cluster characterization and silent cluster activation. Such strategies offer unprecedented versatility in cluster manipulation, bypass the traditional laborious strategies to elicit pathway expression, and provide a new platform for de novo cluster assembly and genome mining for discovering new natural products.
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Affiliation(s)
- Zengyi Shao
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois.,Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa
| | - Huimin Zhao
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois.,Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois.,Departments of Chemistry, Biochemistry, and Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Illinois
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122
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Olano C, García I, González A, Rodriguez M, Rozas D, Rubio J, Sánchez-Hidalgo M, Braña AF, Méndez C, Salas JA. Activation and identification of five clusters for secondary metabolites in Streptomyces albus J1074. Microb Biotechnol 2014; 7:242-56. [PMID: 24593309 PMCID: PMC3992020 DOI: 10.1111/1751-7915.12116] [Citation(s) in RCA: 162] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 01/14/2014] [Accepted: 01/21/2014] [Indexed: 11/28/2022] Open
Abstract
Streptomyces albus J1074 is a streptomycete strain widely used as a host for expression of secondary metabolite gene clusters. Bioinformatic analysis of the genome of this organism predicts the presence of 27 gene clusters for secondary metabolites. We have used three different strategies for the activation of some of these silent/cryptic gene clusters in S. albus J1074: two hybrid polyketide-non-ribosomal peptides (PK-NRP) (antimycin and 6-epi-alteramides), a type I PK (candicidin), a non-ribosomal peptides (NRP) (indigoidine) and glycosylated compounds (paulomycins). By insertion of a strong and constitutive promoter in front of selected genes of two clusters, production of the blue pigment indigoidine and of two novel members of the polycyclic tetramate macrolactam family (6-epi-alteramides A and B) was activated. Overexpression of positive regulatory genes from the same organism also activated the biosynthesis of 6-epi-alteramides and heterologous expression of the regulatory gene pimM of the pimaricin cluster activated the simultaneous production of candicidins and antimycins, suggesting some kind of cross-regulation between both clusters. A cluster for glycosylated compounds (paulomycins) was also identified by comparison of the high-performance liquid chromatography profiles of the wild-type strain with that of a mutant in which two key enzymes of the cluster were simultaneously deleted.
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Affiliation(s)
- Carlos Olano
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de OviedoOviedo, Spain
| | - Ignacio García
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de OviedoOviedo, Spain
| | - Aranzazu González
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de OviedoOviedo, Spain
| | - Miriam Rodriguez
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de OviedoOviedo, Spain
| | - Daniel Rozas
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de OviedoOviedo, Spain
| | - Julio Rubio
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de OviedoOviedo, Spain
| | - Marina Sánchez-Hidalgo
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de OviedoOviedo, Spain
| | - Alfredo F Braña
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de OviedoOviedo, Spain
| | - Carmen Méndez
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de OviedoOviedo, Spain
| | - José A Salas
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de OviedoOviedo, Spain
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123
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Bjerga GEK, Hjerde E, De Santi C, Williamson AK, Smalås AO, Willassen NP, Altermark B. High quality draft genome sequence of Streptomyces sp. strain AW19M42 isolated from a sea squirt in Northern Norway. Stand Genomic Sci 2014; 9:676-86. [PMID: 25197453 PMCID: PMC4148980 DOI: 10.4056/sigs.5038901] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Here we report the 8 Mb high quality draft genome of Streptomyces sp. strain AW19M42, together with specific properties of the organism and the generation, annotation and analysis of its genome sequence. The genome encodes 7,727 putative open reading frames, of which 6,400 could be assigned with COG categories. Also, 62 tRNA genes and 8 rRNA operons were identified. The genome harbors several gene clusters involved in the production of secondary metabolites. Functional screening of the isolate was positive for several enzymatic activities, and some candidate genes coding for those activities are listed in this report. We find that this isolate shows biotechnological potential and is an interesting target for bioprospecting.
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Affiliation(s)
- Gro Elin Kjæreng Bjerga
- Norstruct, Department of Chemistry, Faculty of Science and Technology, University of Tromsø, Norway
| | - Erik Hjerde
- Norstruct, Department of Chemistry, Faculty of Science and Technology, University of Tromsø, Norway
| | - Concetta De Santi
- Norstruct, Department of Chemistry, Faculty of Science and Technology, University of Tromsø, Norway ; Institute of Protein Biochemistry, National Research Council, Naples, Italy
| | - Adele Kim Williamson
- Norstruct, Department of Chemistry, Faculty of Science and Technology, University of Tromsø, Norway
| | - Arne Oskar Smalås
- Norstruct, Department of Chemistry, Faculty of Science and Technology, University of Tromsø, Norway
| | - Nils Peder Willassen
- Norstruct, Department of Chemistry, Faculty of Science and Technology, University of Tromsø, Norway
| | - Bjørn Altermark
- Norstruct, Department of Chemistry, Faculty of Science and Technology, University of Tromsø, Norway
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124
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Zaburannyi N, Rabyk M, Ostash B, Fedorenko V, Luzhetskyy A. Insights into naturally minimised Streptomyces albus J1074 genome. BMC Genomics 2014; 15:97. [PMID: 24495463 PMCID: PMC3937824 DOI: 10.1186/1471-2164-15-97] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 02/01/2014] [Indexed: 11/10/2022] Open
Abstract
Background The Streptomyces albus J1074 strain is one of the most widely used chassis for the heterologous production of bioactive natural products. The fast growth and an efficient genetic system make this strain an attractive model for expressing cryptic biosynthetic pathways to aid drug discovery. Results To improve its capabilities for the heterologous expression of biosynthetic gene clusters, the complete genomic sequence of S. albus J1074 was obtained. With a size of 6,841,649 bp, coding for 5,832 genes, its genome is the smallest within the genus streptomycetes. Genome analysis revealed a strong tendency to reduce the number of genetic duplicates. The whole transcriptomes were sequenced at different time points to identify the early metabolic switch from the exponential to the stationary phase in S. albus J1074. Conclusions S. albus J1074 carries the smallest genome among the completely sequenced species of the genus Streptomyces. The detailed genome and transcriptome analysis discloses its capability to serve as a premium host for the heterologous production of natural products. Moreover, the genome revealed 22 additional putative secondary metabolite gene clusters that reinforce the strain’s potential for natural product synthesis.
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Affiliation(s)
| | | | | | | | - Andriy Luzhetskyy
- Helmholtz-Institute for Pharmaceutical Research Saarland, Saarland University Campus, Building C2,3, 66123 Saarbrücken, Germany.
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125
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Heterologous expression of natural product biosynthetic gene clusters in Streptomyces coelicolor: from genome mining to manipulation of biosynthetic pathways. ACTA ACUST UNITED AC 2014; 41:425-31. [DOI: 10.1007/s10295-013-1348-5] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 09/12/2013] [Indexed: 12/22/2022]
Abstract
Abstract
Heterologous gene expression is one of the main strategies used to access the full biosynthetic potential of actinomycetes, as well as to study the metabolic pathways of natural product biosynthesis and to create unnatural pathways. Streptomyces coelicolor A3(2) is the most studied member of the actinomycetes, bacteria renowned for their prolific capacity to synthesize a wide range of biologically active specialized metabolites. We review here the use of strains of this species for the heterologous production of structurally diverse actinomycete natural products.
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126
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Baltz RH. MbtH homology codes to identify gifted microbes for genome mining. ACTA ACUST UNITED AC 2014; 41:357-69. [DOI: 10.1007/s10295-013-1360-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2013] [Accepted: 09/30/2013] [Indexed: 11/24/2022]
Abstract
Abstract
Advances in DNA sequencing technologies have made it possible to sequence large numbers of microbial genomes rapidly and inexpensively. In recent years, genome sequencing initiatives have demonstrated that actinomycetes with large genomes generally have the genetic potential to produce many secondary metabolites, most of which remain cryptic. Since the numbers of new and novel pathways vary considerably among actinomycetes, and the correct assembly of secondary metabolite pathways containing type I polyketide synthase or nonribosomal peptide synthetase (NRPS) genes is costly and time consuming, it would be advantageous to have simple genetic predictors for the number and potential novelty of secondary metabolite pathways in targeted microorganisms. For secondary metabolite pathways that utilize NRPS mechanisms, the small chaperone-like proteins related to MbtH encoded by Mycobacterium tuberculosis offer unique probes or beacons to identify gifted microbes encoding large numbers of diverse NRPS pathways because of their unique function(s) and small size. The small size of the mbtH-homolog genes makes surveying large numbers of genomes straight-forward with less than ten-fold sequencing coverage. Multiple MbtH orthologs and paralogs have been coupled to generate a 24-mer multiprobe to assign numerical codes to individual MbtH homologs by BLASTp analysis. This multiprobe can be used to identify gifted microbes encoding new and novel secondary metabolites for further focused exploration by extensive DNA sequencing, pathway assembly and annotation, and expression studies in homologous or heterologous hosts.
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Affiliation(s)
- Richard H Baltz
- CognoGen Biotechnology Consulting 7636 Andora Drive 34238 Sarasota FL USA
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127
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Iterative marker excision system. Appl Microbiol Biotechnol 2014; 98:4557-70. [DOI: 10.1007/s00253-014-5523-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 01/03/2014] [Accepted: 01/05/2014] [Indexed: 10/25/2022]
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128
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Genome Shuffling of Streptomyces roseosporus for Improving Daptomycin Production. Appl Biochem Biotechnol 2014; 172:2661-9. [DOI: 10.1007/s12010-013-0687-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Accepted: 12/18/2013] [Indexed: 11/26/2022]
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129
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Bachmann BO, Van Lanen SG, Baltz RH. Microbial genome mining for accelerated natural products discovery: is a renaissance in the making? J Ind Microbiol Biotechnol 2013; 41:175-84. [PMID: 24342967 DOI: 10.1007/s10295-013-1389-9] [Citation(s) in RCA: 185] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Accepted: 11/26/2013] [Indexed: 01/01/2023]
Abstract
Microbial genome mining is a rapidly developing approach to discover new and novel secondary metabolites for drug discovery. Many advances have been made in the past decade to facilitate genome mining, and these are reviewed in this Special Issue of the Journal of Industrial Microbiology and Biotechnology. In this Introductory Review, we discuss the concept of genome mining and why it is important for the revitalization of natural product discovery; what microbes show the most promise for focused genome mining; how microbial genomes can be mined; how genome mining can be leveraged with other technologies; how progress on genome mining can be accelerated; and who should fund future progress in this promising field. We direct interested readers to more focused reviews on the individual topics in this Special Issue for more detailed summaries on the current state-of-the-art.
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Affiliation(s)
- Brian O Bachmann
- Department of Chemistry, Vanderbilt University, 7300 Stevenson Center, Nashville, TN, 37225, USA,
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130
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Genome rearrangements of Streptomyces albus J1074 lead to the carotenoid gene cluster activation. Appl Microbiol Biotechnol 2013; 98:795-806. [PMID: 24337397 DOI: 10.1007/s00253-013-5440-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 11/24/2013] [Accepted: 11/25/2013] [Indexed: 10/25/2022]
Abstract
Streptomyces albus J1074 is a derivative of the S. albus G1 strain defective in SalG1 restriction-modification system. Genome sequencing of S. albus J1074 revealed that the size of its chromosome is 6.8 Mb with unusually short terminal arms of only 0.3 and 0.4 Mb. Here we present our attempts to evaluate the dispensability of subtelomeric regions of the S. albus J1074 chromosome. A number of large site-directed genomic deletions led to circularization of the S. albus J1074 chromosome and to the overall genome reduction by 307 kb. Two spontaneous mutants with an activated carotenoid cluster were obtained. Genome sequencing and transcriptome analysis indicated that phenotypes of these mutants resulted from the right terminal 0.42 Mb chromosomal region deletion, followed by the carotenoid cluster amplification. Our results indicate that the right terminal 0.42 Mb fragment is dispensable under laboratory conditions. In contrast, the left terminal arm of the S. albus J1074 chromosome contains essential genes and only 42 kb terminal region is proved to be dispensable. We identified overexpressed carotenoid compounds and determined fitness costs of the large genomic rearrangements.
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131
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Shao Z, Rao G, Li C, Abil Z, Luo Y, Zhao H. Refactoring the silent spectinabilin gene cluster using a plug-and-play scaffold. ACS Synth Biol 2013; 2:662-9. [PMID: 23968564 DOI: 10.1021/sb400058n] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Natural products (secondary metabolites) are a rich source of compounds with important biological activities. Eliciting pathway expression is always challenging but extremely important in natural product discovery because an individual pathway is tightly controlled through a unique regulation mechanism and hence often remains silent under the routine culturing conditions. To overcome the drawbacks of the traditional approaches that lack general applicability, we developed a simple synthetic biology approach that decouples pathway expression from complex native regulations. Briefly, the entire silent biosynthetic pathway is refactored using a plug-and-play scaffold and a set of heterologous promoters that are functional in a heterologous host under the target culturing condition. Using this strategy, we successfully awakened the silent spectinabilin pathway from Streptomyces orinoci. This strategy bypasses the traditional laborious processes to elicit pathway expression and represents a new platform for discovering novel natural products.
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Affiliation(s)
- Zengyi Shao
- Department
of Chemical and Biomolecular Engineering, ‡Department of Chemistry, and §Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
United States
| | - Guodong Rao
- Department
of Chemical and Biomolecular Engineering, ‡Department of Chemistry, and §Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
United States
| | - Chun Li
- Department
of Chemical and Biomolecular Engineering, ‡Department of Chemistry, and §Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
United States
| | - Zhanar Abil
- Department
of Chemical and Biomolecular Engineering, ‡Department of Chemistry, and §Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
United States
| | - Yunzi Luo
- Department
of Chemical and Biomolecular Engineering, ‡Department of Chemistry, and §Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
United States
| | - Huimin Zhao
- Department
of Chemical and Biomolecular Engineering, ‡Department of Chemistry, and §Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
United States
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132
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Strategies for mining fungal natural products. J Ind Microbiol Biotechnol 2013; 41:301-13. [PMID: 24146366 DOI: 10.1007/s10295-013-1366-3] [Citation(s) in RCA: 133] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 10/05/2013] [Indexed: 10/26/2022]
Abstract
Fungi are well known for their ability to produce a multitude of natural products. On the one hand their potential to provide beneficial antibiotics and immunosuppressants has been maximized by the pharmaceutical industry to service the market with cost-efficient drugs. On the other hand identification of trace amounts of known mycotoxins in food and feed samples is of major importance to ensure consumer health and safety. Although several fungal natural products, their biosynthesis and regulation are known today, recent genome sequences of hundreds of fungal species illustrate that the secondary metabolite potential of fungi has been substantially underestimated. Since expression of genes and subsequent production of the encoded metabolites are frequently cryptic or silent under standard laboratory conditions, strategies for activating these hidden new compounds are essential. This review will cover the latest advances in fungal genome mining undertaken to unlock novel products.
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133
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Rebets Y, Brötz E, Tokovenko B, Luzhetskyy A. Actinomycetes biosynthetic potential: how to bridge in silico and in vivo? J Ind Microbiol Biotechnol 2013; 41:387-402. [PMID: 24127068 DOI: 10.1007/s10295-013-1352-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2013] [Accepted: 09/18/2013] [Indexed: 10/26/2022]
Abstract
Actinomycetes genome sequencing and bioinformatic analyses revealed a large number of "cryptic" gene clusters coding for secondary metabolism. These gene clusters have the potential to increase the chemical diversity of natural products. Indeed, reexamination of well-characterized actinomycetes strains revealed a variety of hidden treasures. Growing information about this metabolic diversity has promoted further development of strategies to discover novel biologically active compounds produced by actinomycetes. This new task for actinomycetes genetics requires the development and use of new approaches and tools. Application of synthetic biology approaches led to the development of a set of strategies and tools to satisfy these new requirements. In this review, we discuss strategies and methods to discover small molecules produced by these fascinating bacteria and also discuss a variety of genetic instruments and regulatory elements used to activate secondary metabolism cryptic genes for the overproduction of these metabolites.
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Affiliation(s)
- Yuriy Rebets
- Helmholtz-Institute for Pharmaceutical Research Saarland, Campus, Building C2.3, Saarbrücken, 66123, Germany
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134
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Chaudhary AK, Dhakal D, Sohng JK. An insight into the "-omics" based engineering of streptomycetes for secondary metabolite overproduction. BIOMED RESEARCH INTERNATIONAL 2013; 2013:968518. [PMID: 24078931 PMCID: PMC3775442 DOI: 10.1155/2013/968518] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Revised: 07/26/2013] [Accepted: 07/28/2013] [Indexed: 11/25/2022]
Abstract
Microorganisms produce a range of chemical substances representing a vast diversity of fascinating molecular architectures not available in any other system. Among them, Streptomyces are frequently used to produce useful enzymes and a wide variety of secondary metabolites with potential biological activities. Streptomyces are preferred over other microorganisms for producing more than half of the clinically useful naturally originating pharmaceuticals. However, these compounds are usually produced in very low amounts (or not at all) under typical laboratory conditions. Despite the superiority of Streptomyces, they still lack well documented genetic information and a large number of in-depth molecular biological tools for strain improvement. Previous attempts to produce high yielding strains required selection of the genetic material through classical mutagenesis for commercial production of secondary metabolites, optimizing culture conditions, and random selection. However, a profound effect on the strategy for strain development has occurred with the recent advancement of whole-genome sequencing, systems biology, and genetic engineering. In this review, we demonstrate a few of the major issues related to the potential of "-omics" technology (genomics, transcriptomics, proteomics, and metabolomics) for improving streptomycetes as an intelligent chemical factory for enhancing the production of useful bioactive compounds.
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Affiliation(s)
- Amit Kumar Chaudhary
- Department of Pharmaceutical Engineering, Institute of Biomolecule Reconstruction, SunMoon University, 100 Kalsan-ri, Tangjeongmyeon, Asan-si, Chungnam 336-708, Republic of Korea
| | - Dipesh Dhakal
- Department of Pharmaceutical Engineering, Institute of Biomolecule Reconstruction, SunMoon University, 100 Kalsan-ri, Tangjeongmyeon, Asan-si, Chungnam 336-708, Republic of Korea
| | - Jae Kyung Sohng
- Department of Pharmaceutical Engineering, Institute of Biomolecule Reconstruction, SunMoon University, 100 Kalsan-ri, Tangjeongmyeon, Asan-si, Chungnam 336-708, Republic of Korea
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135
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Ongley SE, Bian X, Neilan BA, Müller R. Recent advances in the heterologous expression of microbial natural product biosynthetic pathways. Nat Prod Rep 2013; 30:1121-38. [PMID: 23832108 DOI: 10.1039/c3np70034h] [Citation(s) in RCA: 145] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The heterologous expression of microbial natural product biosynthetic pathways coupled with advanced DNA engineering enables optimisation of product yields, functional elucidation of cryptic gene clusters, and generation of novel derivatives. This review summarises the recent advances in cloning and maintenance of natural product biosynthetic gene clusters for heterologous expression and the efforts fundamental for discovering novel natural products in the post-genomics era, with a focus on polyketide synthases (PKSs) and non-ribosomal polypeptide synthetases (NRPS).
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Affiliation(s)
- Sarah E Ongley
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney 2052, Australia
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136
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Jiang M, Fang L, Pfeifer BA. Improved heterologous erythromycin A production through expression plasmid re-design. Biotechnol Prog 2013; 29:862-9. [PMID: 23804312 DOI: 10.1002/btpr.1759] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Revised: 05/14/2013] [Indexed: 01/15/2023]
Abstract
The production of complex compounds from technically convenient microorganisms is an emerging route to the chemical diversity found in the surrounding environment. In this study, the antibiotic compound erythromycin A is produced from Escherichia coli as an alternative to native production through the soil bacterium Saccharopolyspora erythraea. By doing so, there is an opportunity to apply and refine engineering strategies for the manipulation of the erythromycin biosynthetic pathway and for the overproduction of this and other complex natural compounds. Previously, E. coli-derived production was enabled by the introduction of the entire erythromycin pathway (20 genes total) using separately selectable expression plasmids which demonstrated negative effects on final biosynthesis through metabolic burden and plasmid instability. In this study, improvements to final production were made by altering the design of the expression plasmids needed for biosynthetic pathway introduction. Specifically, the total number of genes and plasmids was pruned to reduce both metabolic burden and plasmid instability. Further, a comparison was conducted between species-specific (E. coli vs. S. coelicolor) protein chaperonins. Results indicate improvements in growth and plasmid retention metrics. The newly designed expression platform also increased erythromycin A production levels 5-fold. In conclusion, the steps outlined in this report were designed to upgrade the E. coli erythromycin A production system, led to improved final compound titers, and suggest additional forms of pathway engineering to further improve results from heterologous production attempts.
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Affiliation(s)
- Ming Jiang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
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137
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Abstract
The spread of resistant bacteria, leading to untreatable infections, is a major public health threat but the pace of antibiotic discovery to combat these pathogens has slowed down. Most antibiotics were originally isolated by screening soil-derived actinomycetes during the golden era of antibiotic discovery in the 1940s to 1960s. However, diminishing returns from this discovery platform led to its collapse, and efforts to create a new platform based on target-focused screening of large libraries of synthetic compounds failed, in part owing to the lack of penetration of such compounds through the bacterial envelope. This article considers strategies to re-establish viable platforms for antibiotic discovery. These include investigating untapped natural product sources such as uncultured bacteria, establishing rules of compound penetration to enable the development of synthetic antibiotics, developing species-specific antibiotics and identifying prodrugs that have the potential to eradicate dormant persisters, which are often responsible for hard-to-treat infections.
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Affiliation(s)
- Kim Lewis
- Department of Biology and Antimicrobial Discovery Center, Northeastern University, Boston, Massachusetts 02115, USA.
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138
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Zhang R, Xia H, Xu Q, Dang F, Qin Z. Recombinational cloning of the antibiotic biosynthetic gene clusters in linear plasmid SCP1 ofStreptomyces coelicolorA3(2). FEMS Microbiol Lett 2013; 345:39-48. [DOI: 10.1111/1574-6968.12183] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 04/19/2013] [Accepted: 05/17/2013] [Indexed: 11/30/2022] Open
Affiliation(s)
- Ran Zhang
- Key laboratory of Synthetic Biology; Shanghai Institute of Plant Physiology and Ecology; Shanghai Institutes for Biological Sciences; the Chinese Academy of Sciences; Shanghai; China
| | - Haiyang Xia
- Key laboratory of Synthetic Biology; Shanghai Institute of Plant Physiology and Ecology; Shanghai Institutes for Biological Sciences; the Chinese Academy of Sciences; Shanghai; China
| | - Qingyu Xu
- Key laboratory of Synthetic Biology; Shanghai Institute of Plant Physiology and Ecology; Shanghai Institutes for Biological Sciences; the Chinese Academy of Sciences; Shanghai; China
| | - Fujun Dang
- Key laboratory of Synthetic Biology; Shanghai Institute of Plant Physiology and Ecology; Shanghai Institutes for Biological Sciences; the Chinese Academy of Sciences; Shanghai; China
| | - Zhongjun Qin
- Key laboratory of Synthetic Biology; Shanghai Institute of Plant Physiology and Ecology; Shanghai Institutes for Biological Sciences; the Chinese Academy of Sciences; Shanghai; China
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139
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Young TS, Dorrestein PC, Walsh CT. Codon randomization for rapid exploration of chemical space in thiopeptide antibiotic variants. ACTA ACUST UNITED AC 2013; 19:1600-10. [PMID: 23261603 DOI: 10.1016/j.chembiol.2012.10.013] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Revised: 10/03/2012] [Accepted: 10/08/2012] [Indexed: 01/22/2023]
Abstract
Thiopeptide antibiotics exhibit a profound level of chemical diversity that is installed through cascades of posttranslational modifications on ribosomal peptides. Here, we present a technique to rapidly explore the chemical space of the thiopeptide GE37468 through codon randomization, yielding insights into thiopeptide maturation as well as structure and activity relationships. In this incarnation of the methodology, we randomized seven residues of the prepeptide-coding region, enabling the generation of 133 potential thiopeptide variants. Variant libraries were subsequently queried in two ways. First, high-throughput MALDI-TOF mass spectrometry was applied to colony-level expressions to sample mutants that permitted full maturation of the antibiotic. Second, the activity of producing mutants was detected in an antibiotic overlay assay. In total, 29 of the 133 variants produced mature compound, 12 of which retained antibiotic activity and 1 that had improved activity.
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Affiliation(s)
- Travis S Young
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Armenise 608, Boston, MA 02115, USA
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140
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Stevens DC, Conway KR, Pearce N, Villegas-Peñaranda LR, Garza AG, Boddy CN. Alternative sigma factor over-expression enables heterologous expression of a type II polyketide biosynthetic pathway in Escherichia coli. PLoS One 2013; 8:e64858. [PMID: 23724102 PMCID: PMC3665592 DOI: 10.1371/journal.pone.0064858] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Accepted: 04/22/2013] [Indexed: 02/03/2023] Open
Abstract
Background Heterologous expression of bacterial biosynthetic gene clusters is currently an indispensable tool for characterizing biosynthetic pathways. Development of an effective, general heterologous expression system that can be applied to bioprospecting from metagenomic DNA will enable the discovery of a wealth of new natural products. Methodology We have developed a new Escherichia coli-based heterologous expression system for polyketide biosynthetic gene clusters. We have demonstrated the over-expression of the alternative sigma factor σ54 directly and positively regulates heterologous expression of the oxytetracycline biosynthetic gene cluster in E. coli. Bioinformatics analysis indicates that σ54 promoters are present in nearly 70% of polyketide and non-ribosomal peptide biosynthetic pathways. Conclusions We have demonstrated a new mechanism for heterologous expression of the oxytetracycline polyketide biosynthetic pathway, where high-level pleiotropic sigma factors from the heterologous host directly and positively regulate transcription of the non-native biosynthetic gene cluster. Our bioinformatics analysis is consistent with the hypothesis that heterologous expression mediated by the alternative sigma factor σ54 may be a viable method for the production of additional polyketide products.
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Affiliation(s)
| | - Kyle R. Conway
- Department of Chemistry, University of Ottawa, Ottawa, Ontario, Canada
| | - Nelson Pearce
- Department of Chemistry, University of Ottawa, Ottawa, Ontario, Canada
| | | | - Anthony G. Garza
- Department of Biology, Syracuse University, Syracuse, New York, United States of America
| | - Christopher N. Boddy
- Department of Chemistry, University of Ottawa, Ottawa, Ontario, Canada
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
- * E-mail:
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141
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Identification and biotechnological application of novel regulatory genes involved in Streptomyces polyketide overproduction through reverse engineering strategy. BIOMED RESEARCH INTERNATIONAL 2013; 2013:549737. [PMID: 23555090 PMCID: PMC3603650 DOI: 10.1155/2013/549737] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 12/15/2012] [Accepted: 01/05/2013] [Indexed: 01/24/2023]
Abstract
Polyketide belongs to a family of abundant natural products typically produced by the filamentous soil bacteria Streptomyces. Similar to the biosynthesis of most secondary metabolites produced in the Streptomyces species, polyketide compounds are synthesized through tight regulatory networks in the cell, and thus extremely low levels of polyketides are typically observed in wild-type strains. Although many Streptomyces polyketides and their derivatives have potential to be used as clinically important pharmaceutical drugs, traditional strain improvement strategies such as random recursive mutagenesis have long been practiced with little understanding of the molecular basis underlying enhanced polyketide production. Recently, identifying, understanding, and applying a novel polyketide regulatory system identified from various Omics approaches, has become an important tool for rational Streptomyces strain improvement. In this paper, DNA microarray-driven reverse engineering efforts for improving titers of polyketides are briefly summarized, primarily focusing on our recent results of identification and application of novel global regulatory genes such as wblA, SCO1712, and SCO5426 in Streptomyces species. Sequential targeted gene manipulation involved in polyketide biosynthetic reguation synergistically provided an efficient and rational strategy for Streptomyces strain improvement. Moreover, the engineered regulation-optimized Streptomyces mutant strain was further used as a surrogate host for heterologous expression of polyketide pathway.
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142
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Zotchev SB, Sekurova ON, Katz L. Genome-based bioprospecting of microbes for new therapeutics. Curr Opin Biotechnol 2012; 23:941-7. [DOI: 10.1016/j.copbio.2012.04.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 04/03/2012] [Accepted: 04/05/2012] [Indexed: 01/16/2023]
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143
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Ochi K, Hosaka T. New strategies for drug discovery: activation of silent or weakly expressed microbial gene clusters. Appl Microbiol Biotechnol 2012; 97:87-98. [PMID: 23143535 PMCID: PMC3536979 DOI: 10.1007/s00253-012-4551-9] [Citation(s) in RCA: 206] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Revised: 10/23/2012] [Accepted: 10/24/2012] [Indexed: 11/29/2022]
Abstract
Genome sequencing of Streptomyces, myxobacteria, and fungi showed that although each strain contains genes that encode the enzymes to synthesize a plethora of potential secondary metabolites, only a fraction are expressed during fermentation. Interest has therefore grown in the activation of these cryptic pathways. We review current progress on this topic, describing concepts for activating silent genes, utilization of “natural” mutant-type RNA polymerases and rare earth elements, and the applicability of ribosome engineering to myxobacteria and fungi, the microbial groups known as excellent searching sources, as well as actinomycetes, for secondary metabolites.
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Affiliation(s)
- Kozo Ochi
- Department of Life Science, Hiroshima Institute of Technology, Miyake 2-1-1, Saeki-ku, Hiroshima, 731-5193, Japan.
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144
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Wang P, Kim W, Pickens LB, Gao X, Tang Y. Heterologous Expression and Manipulation of Three Tetracycline Biosynthetic Pathways. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201205426] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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145
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Wang P, Kim W, Pickens LB, Gao X, Tang Y. Heterologous expression and manipulation of three tetracycline biosynthetic pathways. Angew Chem Int Ed Engl 2012; 51:11136-40. [PMID: 23024027 DOI: 10.1002/anie.201205426] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 09/02/2012] [Indexed: 11/11/2022]
Abstract
A very accommodating host: Three tetracycline biosynthetic pathways were overexpressed and manipulated in the heterologous host Streptomyces lividans K4-114. Through the inactivation of various genes and characterization of the resulting biosynthetic intermediates, new tetracycline-modifying enzymes were identified (see scheme).
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Affiliation(s)
- Peng Wang
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA
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146
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Artificial chromosomes to explore and to exploit biosynthetic capabilities of actinomycetes. J Biomed Biotechnol 2012; 2012:462049. [PMID: 22919271 PMCID: PMC3420335 DOI: 10.1155/2012/462049] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Revised: 06/20/2012] [Accepted: 07/04/2012] [Indexed: 12/02/2022] Open
Abstract
Actinomycetes are an important source of biologically active compounds, like antibiotics, antitumor agents, and immunosuppressors. Genome sequencing is revealing that this class of microorganisms has larger genomes relative to other bacteria and uses a considerable fraction of its coding capacity (5–10%) for the production of mostly cryptic secondary metabolites. To access actinomycetes biosynthetic capabilities or to improve the pharmacokinetic properties and production yields of these chemically complex compounds, genetic manipulation of the producer strains can be performed. Heterologous expression in amenable hosts can be useful to exploit and to explore the genetic potential of actinomycetes and not cultivable but interesting bacteria. Artificial chromosomes that can be stably integrated into the Streptomyces genome were constructed and demonstrated to be effective for transferring entire biosynthetic gene clusters from intractable actinomycetes into more suitable hosts. In this paper, the construction of several shuttle Escherichia coli-Streptomyces artificial chromosomes is discussed together with old and new strategies applied to improve heterologous production of secondary metabolites.
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147
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Abstract
Natural products and their derivatives play an important role in modern healthcare as frontline treatments for many diseases and as inspiration for chemically synthesized therapeutics. With advances in sequencing and recombinant DNA technology, many of the biosynthetic pathways responsible for the production of these chemically complex yet valuable compounds have been elucidated. With an ever-expanding toolkit of biosynthetic components, metabolic engineering is an increasingly powerful method to improve natural product titers and generate novel compounds. Heterologous production platforms have enabled access to pathways from difficult to culture strains, systems biology and metabolic modeling tools have resulted in increasing predictive and analytic capabilities, advances in expression systems and regulation have enabled the fine-tuning of pathways for increased efficiency, and characterization of individual pathway components has facilitated the construction of hybrid pathways for the production of new compounds. These advances in the many aspects of metabolic engineering not only have yielded fascinating scientific discoveries but also make it an increasingly viable approach for the optimization of natural product biosynthesis.
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Affiliation(s)
- Lauren B Pickens
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, CA 90095, USA
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148
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Baltz RH. Streptomyces temperate bacteriophage integration systems for stable genetic engineering of actinomycetes (and other organisms). ACTA ACUST UNITED AC 2012; 39:661-72. [DOI: 10.1007/s10295-011-1069-6] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Accepted: 11/23/2011] [Indexed: 12/21/2022]
Abstract
Abstract
ϕC31, ϕBT1, R4, and TG1 are temperate bacteriophages with broad host specificity for species of the genus Streptomyces. They form lysogens by integrating site-specifically into diverse attB sites located within individual structural genes that map to the conserved core region of streptomycete linear chromosomes. The target genes containing the ϕC31, ϕBT1, R4, and TG1 attB sites encode a pirin-like protein, an integral membrane protein, an acyl-CoA synthetase, and an aminotransferase, respectively. These genes are highly conserved within the genus Streptomyces, and somewhat conserved within other actinomycetes. In each case, integration is mediated by a large serine recombinase that catalyzes unidirectional recombination between the bacteriophage attP and chromosomal attB sites. The unidirectional nature of the integration mechanism has been exploited in genetic engineering to produce stable recombinants of streptomycetes, other actinomycetes, eucaryotes, and archaea. The ϕC31 attachment/integration (Att/Int) system has been the most widely used, and it has been coupled with the ϕBT1 Att/Int system to facilitate combinatorial biosynthesis of novel lipopeptide antibiotics in Streptomyces fradiae.
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Affiliation(s)
- Richard H Baltz
- CognoGen Biotechnology Consulting 6438 North Olney Street 46220 Indianapolis IN USA
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149
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Gallo G, Lo Piccolo L, Renzone G, La Rosa R, Scaloni A, Quatrini P, Puglia AM. Differential proteomic analysis of an engineered Streptomyces coelicolor strain reveals metabolic pathways supporting growth on n-hexadecane. Appl Microbiol Biotechnol 2012; 94:1289-301. [DOI: 10.1007/s00253-012-4046-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 03/16/2012] [Accepted: 03/19/2012] [Indexed: 12/12/2022]
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150
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Lee HN, Kim HJ, Kim P, Lee HS, Kim ES. Minimal polyketide pathway expression in an actinorhodin cluster-deleted and regulation-stimulated Streptomyces coelicolor. J Ind Microbiol Biotechnol 2012; 39:805-11. [PMID: 22252445 DOI: 10.1007/s10295-011-1083-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2011] [Accepted: 12/31/2011] [Indexed: 12/26/2022]
Abstract
Along with traditional random mutagenesis-driven strain improvement, cloning and heterologous expression of Streptomyces secondary metabolite gene clusters have become an attractive complementary approach to increase its production titer, of which regulation is typically under tight control via complex multiple regulatory networks present in a metabolite low-producing wild-type strain. In this study, we generated a polyketide non-producing strain by deleting the entire actinorhodin cluster from the chromosome of a previously generated S. coelicolor mutant strain, which was shown to stimulate actinorhodin biosynthesis through deletion of two antibiotic downregulators as well as a polyketide precursor flux downregulator (Kim et al. in Appl Environ Microbiol 77:1872-1877, 2011). Using this engineered S. coelicolor mutant strain as a surrogate host, a model minimal polyketide pathway for aloesaponarin II, an actinorhodin shunt product, was cloned in a high-copy conjugative plasmid, followed by functional pathway expression and quantitative metabolite analysis. Aloesaponarin II production was detected only in the presence of a pathway-specific regulatory gene, actII-ORF4, and its production level was the highest in the actinorhodin cluster-deleted and downregulator-deleted mutant strain, implying that this engineered polyketide pathway-free and regulation-optimized S. coelicolor mutant strain could be used as a general surrogate host for efficient expression of indigenous or foreign polyketide pathways derived from diverse actinomycetes in nature.
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Affiliation(s)
- Han-Na Lee
- Department of Biological Engineering, Inha University, Incheon 402-751, Korea
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