Project Summary Natural products produced by bacteria are a critical resource for discovery of new therapeutics. Synthetic biology approaches such as heterologous expression of biosynthetic gene clusters (BGCs) have leveraged growing capabilities to assume molecular details of natural products produced by sequenced bacteria from genetic data. Methodologies for heterologous expression of BGCs from Streptomyces spp. have benefited from incredible progress and enabled continued discovery of biologically active metabolites from Gram-positive actinobacteria. However, comparatively fewer synthetic biology techniques are available to other groups of bacteria known to be reliable sources of therapeutic leads. Myxobacteria are considered the Gram-negative reciprocal to actinobacteria when describing gifted producers of natural products that have large genomes replete with BGCs. More importantly, metabolites discovered from myxobacteria occupy chemical space unique from actinobacterial metabolites. The long-term objection of this proposal is to increase the synthetic biology toolset available for natural products discovery from myxobacteria. Expanding the number of heterologous host chassis beyond the lone host Myxococcus xanthus and developing novel strategies to generate host platforms will afford alternative approaches to utilize BGCs for natural products discovery. We aim to: 1) assess alternative myxobacterial plasmids and heterologous hosts, 2) develop a predator-prey model system to observe horizontal transfer of BGCs and explore predation-based methods to engineer heterologous hosts, and 3) apply developed myxobacterial tools to enable discovery of novel bacterial metabolites. Successful completion of proposed research will expand synthetic biology tools suited for discovery of natural products and increase investigation of myxobacterial metabolites with antibacterial, antifungal, cytotoxic, antiviral, and immunosuppressive activities. Sustained access to natural products from bacteria benefits human health by providing therapeutic leads, increasing biosynthetic discoveries, and enabling subsequent clinical pharmacology.