Isolation of novel bacteriophages against rare actinomycetes

Actinomycetes are a heterogenous group of Gram-positive bacteria belonging to the phylum Actinomycetota. They constitute one of the largest bacterial phyla and are present in terrestrial and aquatic ecosystems, mainly in soil. Some genera such as Streptomyces are well known as a rich source for novel antibiotics, insecticides and other secondary metabolites that could be useful in medicine, biotechnology, and agriculture, which makes them valuable bacteria for research and applications [1]. However, the phylum also includes pathogenic species, the most well-known is Mycobacterium tuberculosis, the causative agent of tuberculosis. Other species can induce diseases in plants, such as Streptomyces scabies, or in humans and animals, such as Nocardia asteroides, which causes Nocardiosis and mycetoma [1,2]. One approach to control these pathogenic agents might be to use bacteriophages. For rare actinomycetes, bacteriophages have been used as a selective tool to isolate novel natural product producer rather than as potential therapeutic agents [3]. In this regard, we aimed to isolate phages against rare actinomycetes from the DSMZ collection. Ten species of actinomycetes were selected, including Lechevaliera rhizosphaerae, Actinomadura meyerae, and Salinispora pacifica. We used soil samples (compost, fields, sediments) as well as water samples from rivers, lakes or sewage treatment plants. Two phages were isolated from compost samples, one against Actinomadura meyerae and the other against Lechevaliera rhizosphaerae. Characterization of these phages is in progress with host range determination and genomic analysis.

References

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