Answer to Question #144681 in Organic Chemistry for Yuki

Question

What are the general features of a pleiotropic approach to activating a silent biosynthetic gene cluster (BGC)? Briefly outline the main advantage and the main disadvantage of such approaches. Give one example of a pleiotropic approach that can be used to activate silent BGCs.

Answer 1

Manipulating expression of silent biosynthetic genes using CRISPR-Cas9. (a) CRISPR-Cas9 methods adapted for use in streptomycetes are used to insert an active uni- or bi-directional promoter to drive expression of silent BGCs. (b) This approach has been used in S. roseosporus and S. viridochromogenes, among other strains, to induce production of alteramide A, FR-9000098, and a type II PKS-derived pigment.

The method was further extended to two uncharacterized BGCs in Streptomyces roseosporus with homology to clusters with known products.Knock-in of a constitutive promoter upstream of one cluster induced the production of the polycyclic tetramate macrolactams alteramide A and dihydromaltophilin, both previously reported metabolites

The second cluster targeted showed high homology to the known phosphonate FR-900098