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Our studies focus on the mechanisms of molecular wear and tear, terminal marking, protein degradation, and how these processes are altered with age. Molecular wear and tear directly links catalysis with postsynthetic terminal marking. For example, the binding of ligands and catalysis cause conformational changes that are transmitted from the catalytic center to the site of terminal marking and enhance the rates of specific covalent modifications, such as deamidation or oxidation. These oxidations or deamidations can introduce "KFERQ motifs" into proteins, which may permit them to be recognized and transported to the site(s) of complete degradation. Terminally marked proteins accumulate in aging cells and tissues and account for many of the health problems of the elderly. Two-dimensional protein fingerprinting coupled with immunostaining permits identification and characterization of these proteins. Free-radical traps or caloric restriction, which may prevent the formation or enhance the degradation of terminally marked proteins, may be useful in the prevention or treatment of age-associated health problems, including dementia.

Experimental solubilities are reported for anthracene dissolved in 12 binary mixtures containing l-propanol or l-butanol with hexane, heptane, octane, cyclohexane, methylcyclohexane, and 2,2,4-trimethylpentane at 25 OC. Results of these measurements are used to test two mathematical representations based upon the combined nearly ideal binary solvent (NIBS)/Redlich-Kister equation and modified Wilson model. For the systems studied, the combined NIBWRedlich-Kister equation was found to provide the better mathematical representation, with deviations between experimental and back-calculated values being on the order of f1.5 % or less.

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