(27af) Novel Lasso Peptides Produced By Actinobacteria from the Atacama Desert

Natural products from bacteria are a great source of bioactive compounds. Extreme environments such as the Atacama Desert have a unique microbial biodiversity that had the potential to produce novel specialized metabolites¹. Hence, the exploration of this habitat had led to the isolation of Actinobacteria that produce novel compounds, that can serve as therapeutic agents and help in the fight against antibiotic multi-resistance bacteria². An interesting type of natural product are lasso peptides, they are ribosomally synthesized and are characterized by its lasso-structure³ and many of them have showed bioactivity^4,5. The identification of lasso peptide biosynthetic gene clusters (BGCs) can be achieved through genome mining⁶. In this work, we performed first a screening of an Actinobacteria culture collection from the Atacama Desert, using degenerate primers specially designed to detect some of the genes present in the lasso peptide. This allowed us to select candidates for genome sequencing, and later identify the clusters through genome mining. The production of the novel lasso peptides was achieved by cloning the BGCs under a strong promoter into a Streptomyces heterologous host. Bioactivity studies of the lasso peptides showed that they have the potential to be used as therapeutic agents.

References:

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