FIGURE 4.

CMD patient lymphoblasts are deficient for LARGE GlcA-T activity. A, representative HPLC profiles from the LC-18 column of the product obtained from reactions in which solubilized microsomes extracted from control or CMD Patient #1 lymphoblasts served as the source of enzyme and Xyl-α1,3-GlcA-β-MU as substrate, in the presence (top) or absence (bottom) of the donor sugar UDP-GlcA. P, product. S, unreacted substrate. Dotted line, % buffer B. Asterisks indicate nonspecific peak observed regardless of presence or absence of the donor substrate. B, GlcA-T activity on the solubilized microsomes extracted from the control or the CMD Patient #1 lymphoblasts. Relative activity (%) with respect to the control, and the standard deviation in triplicate experiments, are shown. C, representative HPLC profiles of the GlcA-T assay on solubilized microsomes extracted from control or CMD Patient #2 myoblasts. Note that the elution profiles are different from those in A, because a slightly lower concentration of buffer B was used for the separation.