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One hypothesis for atherosclerotic lesion formation is the response to injury hypothesis. If catabolism of the ground substance of the intima of blood vessels is viewed as an injury, then inhibition of this catabolism could lead to a decrease in atherosclerotic lesions. Arylsulfatase B catalyses the desulfation of glycosaminoglycans in the catabolism of the intimal ground substance. We have found that ascorbic acid inhibits arylsulfatase B (Km = 2.06 mM, KI = 4.89 mM), thus providing a possible mechanism by which ascorbic acid may decrease atherosclerosis.

The quenching of the fluorescence of liver alcohol dehydrogenase by acrylamide has been studied as a function of excitation and emission wavelength. Downward curving Stern-Volmer plots are found, providing further support for the notion that Trp-15 of the protein is surface exposed and that Trp-314 is extensively buried within the protein. The acrylamide quenching of the binary complex formed between the protein and NAD+ was also studied. The quenching pattern in this case is found to be complicated due to the interaction of acrylamide with the binary complex. Independent evidence for the fact that acrylamide binds to the binary complex is obtained from enzyme inhibition studies and from NAD+ binding studies showing acrylamide to bind with positive cooperativity with respect to the coenzyme. When the interaction of acrylamide with the binary complex is taken into consideration, however, the quenching data can be interpreted as indicating that the binding of NAD+ to the protein does not induce a conformational change that leads to the exposure of Trp-314.

A spectroscopic displacement method is used to determine association constants of beta-cyclodextrin with compounds that are spectroscopically transparent. These compounds are adamantanecarboxylate and structurally related compounds. Association constants obtained are compared to values obtained by other methods. It is shown that for all types of displacement techniques a distinction must be made between free and total concentrations of ligand in cases of strong binding.