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Medium chain acyl-CoA dehydrogenase deficiency (MCADD) is a common biochemical genetic disorder in the US. Nearly 90% of alleles from MCADD patients contain a common mutation in the ACADM (c.985A>G). The change replaces a lysine with a glutamate (K304E), causing improper folding. The K304E protein can fold to a mature form and is then stable and active when expressed in a prokaryotic system with molecular chaperonins. The goal of this project was to identify chemical chaperones capable of stabilizing the K304E MCAD protein. Since even a small amount of MCAD activity restores metabolic flux, inducing intra-mitochondrial folding of K304E MCAD has the potential to be protective for patients. To demonstrate proof of principle, dimethylsulfoxide, glycerol, betaine, trimethylamine N-oxide (TMAO), and L-proline were tested for the ability to increase MCAD activity in lymphoblasts having c.985G>A alleles. TMAO and glycerol significantly increased MCAD activity in these cells. Phenylbutyrate is converted to its CoA ester form and metabolized to phenylacetyl-CoA through β-oxidation initiated by MCAD. As a substrate analogue for MCAD, phenylbutyryl-CoA is expected to improve protein stability. Experiments in HEK293 cells containing inducible wild type or K304E MCAD alleles, phenylbutyrate increased wild type MCAD activity by 30% and K304E MCAD activity by 154%. A clinical trial testing the efficacy of phenylbutyrate in MCAD patients is underway. Drug targeting sites were also investigated using molecular modeling. The docking site for electron transfer flavoprotein (ETF) was hypothesized to be a viable site. Twelve amino acid peptides with variable sequences were synthesized based on ETF βArg191-βLys202. One of the peptides significantly increased thermal stability of K304E MCAD. Circular dichroism spectroscopy confirmed binding of the synthetic peptide, inducing a shift in the Tm of the enzymes. The ETF docking peptide analogue also protected K304E MCAD protein against limited proteolysis by Staphylococcus aureus V8. These results confirm that ETF docking site is a viable target for MCADD. PUBLIC HEALTH SIGNIFICANCE: Even though newborn screening has reduced the mortality of the MCADD, patients still require frequent hospital visits during metabolic decompensation. New treatments for MCADD will significantly reduce the burden of disease on these patients.

This dissertation on Rachmaninoff's Rhapsody on a Theme by Paganini, Op.43 is divided into four parts: 1) historical background and the state of the sources, 2) analysis, 3) semantic issues related to analysis (discourse), and 4) performance and analysis. The analytical study, which constitutes the main body of this research, demonstrates how Rachmaninoff organically produces the variations in relation to the theme, designs the large-scale tonal and formal organization, and unifies the theme and variations as a whole. The selected analytical approach is linear in orientation - that is, Schenkerian. In the course of the analysis, close attention is paid to motivic detail; the analytical chapter carefully examines how the tonal structure and motivic elements in the theme are transformed, repeated, concealed, and expanded throughout the variations. As documented by a study of the manuscripts, the analysis also facilitates insight into the genesis and structure of the Rhapsody. How Rachmaninoff develops his ideas through several notebooks - including sketches and drafts - is described. Later parts of the dissertation deal with programmatic aspects of the Rhapsody. Related to the composer's significant use of the Dies Irae melody, semantic issues concerning "love and death" are taken into account and closely related to the specific structure of the piece. Rachmaninoff's symphonic poem, The Isle of the Dead, is a work which bears some intriguing resemblances to the Rhapsody in its larger structure as well as its ideology. Therefore, an interpretation of this work is provided to show the special relationship between the two pieces. The last chapter presents a discussion of two recordings of the Rhapsody by Rachmaninoff and Moiseiwitsch made in 1934 and 1938 respectively. Comparing and contrasting the different interpretations of each variation in these two historical recordings, this concluding part of the study explores ways in which analysis can be realized through performance.