Fig 4.

Assay for Cps2I glycosyltransferase activity. Cps2E-containing membranes (3 μg of total protein) were incubated with membranes containing the indicated glycosyltransferases (3 μg of total protein) and nucleotide sugars. Reactions were processed as described for Fig. 2 and contained 0.008% NP-40, 10 mM MnCl₂, 1 mM DTT, 0.075 μCi of UDP-[¹⁴C]Glc (300 mCi/mmol), and, where indicated, 0.1 mM dTDP-Rha or 0.1 mM dTDP-Rha and 0.1 mM UDP-GlcUA. Lanes show enzymes in the reaction mixtures: E, Cps2E; T, Cps2T; F, Cps2F; G, Cps2G; and I, Cps2I. Arrows indicate the locations of the origin (O) and the products formed by Cps2E, Cps2T, Cps2F, and Cps2G.