4000 metres closer to novel antibiotics: a bioprospecting tale of three Streptomyces strains from the Andes

Bioprospecting of underexplored environments and microbiomes remains one of the core strategies for drug discovery. Páramos, a high-altitude ecosystem and evolutionary hotspot in the northern Andes of South America, harbour microbial diversity yet to be studied for its potential for antibiotic production. In this project, three strains (CG885, CG893 and CG926) isolated from a páramo in Colombia were explored using phylogenetic and genome mining tools to uncover their potential for novel antimicrobials. Taxonomic characterisation of three isolates suggested strains CG885 and CG893 can be classified as Streptomyces pratensis while strain CG926 is likely to be a new Streptomyces species. All three strains showed the biosynthetic coding capacity characteristic of streptomycetes and a diverse repertoire of biosynthetic gene cluster types likely to encode for novel specialised metabolites. One cluster in the strain CG926, for instance, is predicted to encode for a new halogenated compound containing the unusual nonproteinogenic amino acid piperazic acid with no known analogue. Integration of these results with phenotypic and metabolomic data will enable the assessment of these molecules and their antimicrobial activity. Overall, these results demonstrated that these three strains from an underexplored environment harbour the potential to become producers of novel antibiotics.