With this CAREER Award, the Chemical Synthesis Program of the NSF Division of Chemistry is supporting the research of Professor Noah Burns at Stanford University. The research improves our fundamental understanding of lipid membranes by synthesizing them from readily available starting materials and then measuring their physical properties. Lipid membranes are universal features of living systems, constituting protective inner and outer barriers of cells. Nature has produced a fascinating array of lipid structures that dictate the function of biological membranes, and organisms devote considerable energy to the synthesis and maintenance of such compositions. Professor Burns is investigating new synthetic reactions to make lipids that are not readily available from natural sources. This research increases our understanding how lipids are formed and how they can be utilized biological and non-biological systems. This research is multidisciplinary and extends beyond the typical boundaries of synthetic chemistry or biology. Through a strong established collaboration, synthetic chemists are working with physical chemists to study the properties of the synthesized lipids, thus tackling larger scientific questions regarding the function of molecules. In order to impact the broader community, Professor Burns and his research group are making use of social media. Platforms such as Twitter and Instagram offer unique opportunities for cross-talk. Twitter (@burnschemistry) is used to communicate findings from the Professor Burns' lab in order to alert the chemical community to exciting new advances. Instagram (@burnschemistry) is used to promote the fun, exciting, and human side of organic chemistry research. The use of social media is intended to excite more young people to consider advanced degrees or careers in chemistry.
Professor Burns is developing selective and efficient syntheses of three classes of noncanonical membrane lipids in order to fully investigate their biophysical properties. Highly unusual polycyclobutane-containing ladderane phospholipids, monocyclohexane- and polycyclopentane-containing tetraether lipids, and polychlorinated sulfolipids have been identified from anaerobic ammonium-oxidizing bacteria, archaea, and freshwater algae, respectively. This research is establishing approaches for accessing each of these three classes of noncanonical membrane lipids. This chemical synthesis is impacting the broader synthetic community by providing new reaction methodologies and new strategies for accessing functional group motifs that are of interest in other contexts. The biophysical properties of natural and non-natural lipids are analyzed utilizing modern techniques to verify self-assembled structures, to measure monolayer density and compressibility, to evaluate permeability of ions and small molecules, and to interrogate membrane thickness and structure. This information has general implications for manipulating membrane properties and designing new soft materials.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
