Planta Med 2023; 89(14): 1361
DOI: 10.1055/s-0043-1774072
Abstracts
Tuesday 4th July 2023 | Poster Session II
Phytochemistry II - Antimicrobials; Cosmetics; Essential oils; Nutraceuticals; Biotechnology

Streptomyces spp. from the rhizosphere of Leontopodium nivale subsp. alpinum – uncovering potential for the biosynthesis of secondary metabolites

Anna Vignolle
1   Department of Pharmaceutical Sciences, Division of Pharmacognosy, University of Vienna, 1090 Vienna, Austria
,
Martin Zehl
2   Mass Spectrometry Centre, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
,
Petra Pjevac
3   Joint Microbiome Facility, Medical University of Vienna and University of Vienna, 1030 Vienna, Austria
,
Sergey B. Zotchev
1   Department of Pharmaceutical Sciences, Division of Pharmacognosy, University of Vienna, 1090 Vienna, Austria
› Author Affiliations
› Further Information
Also available ateRef
 

Actinomycetes, especially the genus Streptomyces, are prolific producers of natural products, from which many therapeutically valuable molecules have been isolated. With increasing rediscovery rates, the focus has shifted to Streptomyces from unique ecological niches for the discovery of new natural products. One such ecological niche is the plant rhizosphere, characterised by chemical interactions between the plant and the rhizobiome, which can elicit the production of antibiotics by Streptomyces [1].

Rhizosphere soil of the rare alpine plant Leontopodium nivale subsp. alpinum was used to isolate 77 actinomycetes [2] of which 20 strains belonging to the genus Streptomyces were chosen to characterise their secondary metabolite production potential and to discover novel natural products.

The genomes of the 20 Streptomyces spp. strains were sequenced and analysed with antiSMASHv6.0 software [3]. A total of 601 biosynthetic gene clusters were detected, 119 of which are possibly unique.

The 20 strains were cultivated in the fermentation media MYM, PM4 and SM17. Methanolic extracts were prepared from the fermentation broths and tested for antimicrobial activity against Bacillus subtilis, Staphylococcus carnosus, Escherichia coli, Saccharomyces cerevisiae and Pseudomonas fluorescens. Of the 60 tested extracts 37% displayed antimicrobial activity. LC-MS analysis of some methanolic extracts resulted in the detection of 19 known compounds, including nonactin, tambromycins and heronamides, and 3 potentially novel secondary metabolites. To facilitate genetic engineering aimed at eliciting expression of potentially novel clusters and hence production of their cognate secondary metabolites, we successfully established gene transfer systems for 11 strains.



Publication History

Article published online:
16 November 2023

© 2023. Thieme. All rights reserved.

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

 

  • References

  • 1 van Bergeijk DA, Terlouw BR, Medema MH, van Wezel GP.. Ecology and genomics of Actinobacteria: new concepts for natural product discovery. Nat Rev Microbiol 2020; 18: 546-558
    PubMedSearch in Google Scholar
  • 2 Oberhofer M, Hess J, Leutgeb M, Gossnitzer F, Rattei T, Wawrosch C, Zotchev SB.. Exploring Actinobacteria Associated With Rhizosphere and Endosphere of the Native Alpine Medicinal Plant Leontopodium nivale Subspecies alpinum. Front Microbiol 2019; 10: 2531
    PubMedSearch in Google Scholar
  • 3 Blin K, Shaw S, Kloosterman AM, Charlop-Powers Z, van Wezel GP, Medema MH, Weber T.. antiSMASH 6.0: improving cluster detection and comparison capabilities. Nucleic Acids Res 2021; 49: W29-W35
    CrossrefPubMedSearch in Google Scholar