Plants and microorganisms produce a large variety of natural molecules with complex chemical architecture and beneficial properties. These small molecules are made by an assembly-line-like machinery composed of enzymes in the producing organisms. This proposal will probe the structure and mechanism of enzymes responsible for the biosynthesis of a specific class of peptide natural products. Using an interdisciplinary approach, the researchers will determine the atomic resolution structures of key machinery components using X-ray diffraction. The structural work will be complemented by synthetic organic chemistry and molecular biology approaches. Overall, the results will both provide insight into the fundamental chemistry and will help guide the metabolic engineering of biosynthetic pathways to produce useful molecules. Coupled to the research plan is a comprehensive education and outreach plan that will exploit the results and approaches to engage high school, undergraduate and graduate students.
With this award, the Chemistry of Life Processes Program in the Chemistry Division is funding Dr. Steven Bruner from the University of Florida to study the structure and mechanism of complex, multidomain enzymes responsible for the biosynthesis of non-ribosomal peptide natural products. These pathways are responsible for the production of a wide range of structurally diverse and therapeutically important products. The proposal will use an interdisciplinary approach focused on small molecule probes in combination with protein X-ray crystallography and mechanistic enzymology. The work will address key unanswered questions in regard to the structure and mechanism of peptide construction: amide bond formation, amino acid epimerization and peptide cyclization. Expanding on prior results, a structural genomics approach will be used with enzymes of the T. fusca fuscachelin pathway as a model for all non-ribosomal peptide pathways. Specific focus will be on the structural characterization of protein/protein interactions, substrate trafficking and unresolved mechanistic questions. The broader impacts of this work encompass multiple disciplines, as the results of this program have application and impact in diverse areas of secondary metabolite production, including metabolic engineering and synthetic biology. In addition, a strong educational component is present, incorporating aspects of the research plan to introduce students at many levels to the interdisciplinary approaches of chemical biology.
