Bilirubin conjugation with xylose

With washed microsomal preparations from the liver of guinea pig, rat, rabbit, mouse, and cat, conjugation of bilirubin also occurred at appreciable rates in the absence of added bivalent cation (P3). With digitonin-activated preparations from rat liver, glycosyl transfer rates were, respectively, 16-33%, 0-38%, and 58-78% of the values found at nearsaturation of Mg + when UDP-glucuronic acid, UDP-xylose, or UDP-glucose were assayed (F3, HIO). The great variability of the rates could point to an artifact. 

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