Publications by authors named "Jean A Boutros"

In this study, we explored structural differences of five commercial samples of yeast β-glucan. Samples were assayed for their β-glucan content and the yeast storage carbohydrate, glycogen. The β-glucan content ranged from 74% to 86%, the glycogen content varied from 0 to 20%.

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Accurate determination of nitrite either as such or as the breakdown product of nitric oxide (NO) is critical in a host of enzymatic reactions in various settings addressing structure-function relationships, as well as mechanisms and kinetics of molecular operation of enzymes. The most common way to quantify nitrite, for instance in nitric oxide synthase (NOS) mechanistic investigations, is the spectrophotometric assay based on the Griess reaction through external standard calibration. This assay is based on a two-step diazotization reaction, in which a cationic diazonium derivative of sulfanilamide is formed as intermediate before the final absorbing azo-product.

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Thin film direct electrochemistry shows that the oxygenase domain of neuronal nitric oxide synthase undergoes reversible electron transfer with an underlying electrode. The midpotential of the FeIII/FeII couple is found to be modulated by both the binding of the tetrahydropterin cofactor and the pH of the buffer medium.

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