scholarly journals Characterization and Engineering of Streptomyces griseofuscus DSM 40191 as a Potential Host for Heterologous Expression of Biosynthetic Gene Clusters

2020 ◽  
Author(s):  
Tetiana Gren ◽  
Christopher M. Whitford ◽  
Omkar S. Mohite ◽  
Tue S. Jørgensen ◽  
Eftychia E. Kontou ◽  
...  

AbstractStreptomyces griseofuscus DSM 40191 is a fast growing Streptomyces strain that remains largely underexplored as a heterologous host. Here, we report the genome mining of S. griseofuscus, followed by the detailed exploration of its phenotype, including production of native secondary metabolites and ability to utilise carbon, nitrogen, sulphur and phosphorus sources. Furthermore, several routes for genetic engineering of S. griseofuscus were explored, including use of GusA-based vectors, CRISPR-Cas9 and CRISPR-cBEST-mediated knockouts. Using CRISPR-BEST technology, core genes of 4 biosynthetic gene clusters (BGCs) that are situated on the chromosome arms were inactivated and the outcomes of the inactivations were tested. Two out of the three native plasmids were cured using CRISPR-Cas9 technology, leading to the generation of strain S. griseofuscus DEL1. DEL1 was further modified by full deletion of a pentamycin BGC and an unknown NRPS BGC, leading to the generation of strain DEL2, lacking approx. 500 kbp of the genome, which corresponds to a 5,19% genome reduction. Sequencing confirmed that DEL2 does not bear any crucial off-target effects or rearrangements in its genome. It can be characterized by faster growth and inability to produce three main native metabolites of S. griseofuscus: lankacidin, lankamycin, pentamycin and their derivatives. To test the ability of DEL2 to heterologously produce secondary metabolites, the actinorhodin BGC was used. We were able to confirm the production of actinorhodin by both S. griseofuscus wild type and DEL2. We believe that this strain will serve as a good chassis for heterologous expression of BGCs.ImportanceThe rise of antibacterial resistance calls on the development of the next generation of antibiotics, majority of which are derived from natural compounds, produced by actinomycetes. The manipulation, refactoring and expression of BGCs coding for such natural products is a promising approach in secondary metabolite discovery. Thus, the development of a versatile panel of heterologous hosts for the expression of BGCs is essential. We believe that first-to-date systematic, detailed characterisation of S. griseofuscus, a highly promising chassis strain, will not only facilitate the further development of this particular strain, but also will set a blueprint for characterisation of other potential hosts.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tetiana Gren ◽  
Christopher M. Whitford ◽  
Omkar S. Mohite ◽  
Tue S. Jørgensen ◽  
Eftychia E. Kontou ◽  
...  

AbstractStreptomyces griseofuscus DSM 40191 is a fast growing Streptomyces strain that remains largely underexplored as a heterologous host. Here, we report the genome mining of S. griseofuscus, followed by the detailed exploration of its phenotype, including the production of native secondary metabolites and ability to utilise carbon, nitrogen, sulphur and phosphorus sources. Furthermore, several routes for genetic engineering of S. griseofuscus were explored, including use of GusA-based vectors, CRISPR-Cas9 and CRISPR-cBEST-mediated knockouts. Two out of the three native plasmids were cured using CRISPR-Cas9 technology, leading to the generation of strain S. griseofuscus DEL1. DEL1 was further modified by the full deletion of a pentamycin BGC and an unknown NRPS BGC, leading to the generation of strain DEL2, lacking approx. 500 kbp of the genome, which corresponds to a 5.19% genome reduction. DEL2 can be characterized by faster growth and inability to produce three main native metabolites: lankacidin, lankamycin, pentamycin and their derivatives. To test the ability of DEL2 to heterologously produce secondary metabolites, the actinorhodin BGC was used. We were able to observe a formation of a blue halo, indicating a potential production of actinorhodin by both DEL2 and a wild type.


Author(s):  
Xiyan Wang ◽  
Thomas Isbrandt ◽  
Emil Ørsted Christensen ◽  
Jette Melchiorsen ◽  
Thomas Ostenfeld Larsen ◽  
...  

Pigmented Pseudoalteromonas strains are renowned for their production of secondary metabolites, and genome mining has revealed a high number of biosynthetic gene clusters (BGCs) for which the chemistry is unknown. Identification of those BGCs is a prerequisite for linking products to gene clusters and for further exploitation through heterologous expression.


2016 ◽  
Vol 82 (19) ◽  
pp. 5795-5805 ◽  
Author(s):  
Min Xu ◽  
Yemin Wang ◽  
Zhilong Zhao ◽  
Guixi Gao ◽  
Sheng-Xiong Huang ◽  
...  

ABSTRACTGenome sequencing projects in the last decade revealed numerous cryptic biosynthetic pathways for unknown secondary metabolites in microbes, revitalizing drug discovery from microbial metabolites by approaches called genome mining. In this work, we developed a heterologous expression and functional screening approach for genome mining from genomic bacterial artificial chromosome (BAC) libraries inStreptomycesspp. We demonstrate mining from a strain ofStreptomyces rochei, which is known to produce streptothricins and borrelidin, by expressing its BAC library in the surrogate hostStreptomyces lividansSBT5, and screening for antimicrobial activity. In addition to the successful capture of the streptothricin and borrelidin biosynthetic gene clusters, we discovered two novel linear lipopeptides and their corresponding biosynthetic gene cluster, as well as a novel cryptic gene cluster for an unknown antibiotic fromS. rochei. This high-throughput functional genome mining approach can be easily applied to other streptomycetes, and it is very suitable for the large-scale screening of genomic BAC libraries for bioactive natural products and the corresponding biosynthetic pathways.IMPORTANCEMicrobial genomes encode numerous cryptic biosynthetic gene clusters for unknown small metabolites with potential biological activities. Several genome mining approaches have been developed to activate and bring these cryptic metabolites to biological tests for future drug discovery. Previous sequence-guided procedures relied on bioinformatic analysis to predict potentially interesting biosynthetic gene clusters. In this study, we describe an efficient approach based on heterologous expression and functional screening of a whole-genome library for the mining of bioactive metabolites fromStreptomyces. The usefulness of this function-driven approach was demonstrated by the capture of four large biosynthetic gene clusters for metabolites of various chemical types, including streptothricins, borrelidin, two novel lipopeptides, and one unknown antibiotic fromStreptomyces rocheiSal35. The transfer, expression, and screening of the library were all performed in a high-throughput way, so that this approach is scalable and adaptable to industrial automation for next-generation antibiotic discovery.


2021 ◽  
Vol 11 (4) ◽  
pp. 1851
Author(s):  
Van Thuy Thi Pham ◽  
Chung Thanh Nguyen ◽  
Dipesh Dhakal ◽  
Hue Thi Nguyen ◽  
Tae-Su Kim ◽  
...  

Streptomyces is a significant source of natural products that are used as therapeutic antibiotics, anticancer and antitumor agents, pesticides, and dyes. Recently, with the advances in metabolite analysis, many new secondary metabolites have been characterized. Moreover, genome mining approaches demonstrate that many silent and cryptic biosynthetic gene clusters (BGCs) and many secondary metabolites are produced in very low amounts under laboratory conditions. One strain many compounds (OSMAC), overexpression/deletion of regulatory genes, ribosome engineering, and promoter replacement have been utilized to activate or enhance the production titer of target compounds. Hence, the heterologous expression of BGCs by transferring to a suitable production platform has been successfully employed for the detection, characterization, and yield quantity production of many secondary metabolites. In this review, we introduce the systematic approach for the heterologous production of secondary metabolites from Streptomyces in Streptomyces and other hosts, the genome analysis tools, the host selection, and the development of genetic control elements for heterologous expression and the production of secondary metabolites.


2018 ◽  
Author(s):  
Inge Kjærbølling ◽  
Tammi Vesth ◽  
Mikael R. Andersen

AbstractFungal secondary metabolites are a rich source of valuable natural products. Genome sequencing have revealed an enormous potential from predicted biosynthetic gene clusters. It is however currently a time consuming task and an unfeasible task to characterize all biosynthetic gene cluster and to identify possible uses of the compounds. A rational approach is needed to identify promising gene clusters responsible for producing valuable compounds. Several valuable bioactive clusters have been shown to include a resistance gene which is a paralog of the target gene inhibited by the compound. This mechanism can be used to design a rational approach selecting those clusters.We have developed a pipeline FRIGG (Fungal Resistance Gene-directed Genome mining) identifying putative resistance genes found in biosynthetic gene clusters based on homology patterns of the cluster genes. The FRIGG pipeline has been run using 51 Aspergillus and Penicillium genomes, identifying 72 unique protein families with putative resistance genes using various settings in the pipeline. The pipeline was also able to identify the characterized resistance gene inpE from the Fellutamide B cluster thereby validating the approach.We have successfully developed an approach identifying putative valuable bio-active clusters based on a specific resistance mechanism. This approach will be highly useful as an ever increasing amount of genomic data becomes available — the art of identifying and selecting clusters producing novel valuable compounds will only become more crucial.ImportanceSpecies belonging to the Aspergillus genus are known to produce a large number of secondary metabolites, some of these compounds are bioactive and used as pharmaceuticals such as penicillin, cyclosporin and statin. With whole genome sequencing it became apparent that the genetic potential for secondary metabolite production is much bigger than expected. As an increasing number of species are whole genome sequenced an immense number of secondary metabolite genes are predicted and the question of how to selectively identify novel bioactive compounds from this information arises. To address this question, we have created a pipeline identifying genes likely involved in the production of bioactive compounds based on a resistance gene hypothesis approach.


Sign in / Sign up

Export Citation Format

Share Document