With this award, the Organic and Macromolecular Chemistry Program supports Neil Marsh and Hashim M. Al-Hashimi both of the University of Michigan whose research will advance the area of protein design by engineering some of the novel properties of fluorocarbons into biological molecules. This will be achieved by synthesizing proteins that contain extensively fluorinated ('fluorous') analogs of hydrophobic amino acids in their hydrophobic cores. Fluorous amino acids are predicted to stabilize proteins against unfolding by heat and organic solvents and to facilitate protein: protein recognition through specific fluorocarbon-fluorocarbon interactions. Fluorinated versions of a dimeric RNA-binding protein, Rop, will be synthesized in which the hydrophobic core of Rop will be repacked with the fluorous analog of leucine, hexafluoroleucine. This protein is small enough (63 residues) to be efficiently synthesized by peptide synthesis, which will allow fluorous amino acids to be introduced site specifically. Rop protein has been extensively used as a model system for investigating protein stability and folding, and as a template for protein re-design. These data will serve as a useful reference for the present study. A variety of physical techniques (such as circular dichroism, microcalorimetry and analytical ultracentrifugation) will be used to investigate the effect of fluorination on the biological activity, structure and stability of fluorous Rop proteins. An important innovation will be the use of residual dipolar coupling (RDC) NMR measurements to perform detailed comparisons of the effect of fluorination on the structure and conformational rigidity of the protein. The experiments will address fundamental questions about the impact of fluorination on protein structure and dynamics. This award from the Organic and Macromolecular Chemistry Program supports Professors Neil Marsh and Hashim M. Al-Hashimi both of the University of Michigan whose research will impact attempts to design biosensors and enzymes used in industrial processes, where stability towards extremes of temperature and pH and towards organic solvents is necessary. There is the potential for fluorous proteins to find uses in medical imaging by exploiting the high NMR sensitivity of Fluorine 19 or their enhanced biological stability could lead to uses as therapeutic agents or vehicles for drug delivery. The project will advance the education, training and professional development of undergraduates, graduate students and postdoctoral scientists in the inter-disciplinary area of chemical biology and biophysics. To broaden their education further, a joint interdisciplinary group meeting and journal club will be initiated. Their professional development will be enhanced by active participation in the dissemination of their results, both through drafting manuscripts and progress reports, and through oral and poster presentations at local and national scientific meetings.
