S112: Discovery, Design, and Development of Novel Natural Products via Synthetic Biology

Microorganisms produce a myriad array of natural products or secondary metabolites that are of biomedical and biotechnological importance. However, the discovery and sustainable production of these compounds are often limited by our capability to manipulate the biosynthetic genes or clusters in either the native or the heterologous host. To overcome this key limitation in the natural product biosynthesis research area, my group has been developing a novel synthetic biology strategy based on our recently developed DNA assembler method for discovery, characterization, and engineering of novel natural products in microorganisms. By taking advantage of the highly efficient yeast in vivo homologous recombination mechanism, this strategy synthesizes an entire expression vector containing the target biosynthetic pathway and the genetic elements needed for DNA maintenance and replication in Saccharomyces cerevisiae, Escherichia coli, and a target heterologous expression host in a single-step manner.  Since all the fragments are prepared by PCR, various manipulations including site-directed mutagenesis, scar-less gene deletion and artificial gene cluster construction can be easily achieved. As proof of concept, two important biosynthetic pathways from Streptomyces including the aureothin and spectinabilin biosynthetic pathways were selected for characterization and engineering. Such a strategy with unprecedented flexibility and versatility has many applications in heterologous expression, pathway functional studies, and combinatorial biosynthesis.