The Modulation of Copper Chaperone/Transporter Orthologue Expression Enhances Secondary Metabolism in Streptomycetes.

Streptomycetes are important biotechnological bacteria that produce several clinically bioactive compounds. They have a complex development, including hyphae differentiation and sporulation. Cytosolic copper is a well-known modulator of differentiation and secondary metabolism. The interruption of the (copper chaperone, mutant) blocks and reduces (P-type ATPase copper export) expressions, decreasing copper export and increasing cytosolic copper. This mutation triggers the expression of 13 secondary metabolite clusters, including cryptic pathways, during the whole developmental cycle, skipping the vegetative, non-productive stage. As a proof of concept, here, we tested whether the knockdown of the orthologue expression can enhance secondary metabolism in streptomycetes. We created a consensus antisense mRNA from the sequences of seven key streptomycetes, which helped to increase the cytosolic copper in , albeit to a lower level than in the mutant. This antisense mRNA affected the production of at least six secondary metabolites (CDA, 2-methylisoborneol, undecylprodigiosin, tetrahydroxynaphtalene, α-actinorhodin, ε-actinorhodin) in the , and five (phenanthroviridin, alkylresorcinol, chloramphenicol, pikromycin, jadomycin G) in the ; it also helped to alter the metabolome. The consensus antisense mRNA designed here constitutes a tool for the knockdown of expression and for the enhancement of ' secondary metabolism.