FIG. 4.

Effect of potassium glutamate or choline chloride on the production of neutral products from UDP-glucose. Assays were performed in the presence of potassium glutamate (A) or choline chloride (B) at the concentrations indicated. The basal levels of activity were 0.82 and 1.05 nmol of UDP-glucose converted to neutral product under standard reaction conditions for the assays performed with potassium glutamate and choline chloride, respectively. Sephadex G-50 column chromatography revealed that the primary neutral product formed in the presence of high potassium glutamate and choline chloride concentrations eluted later than cyclic β-(1,2)-glucan, suggesting that a membrane-associated enzyme distinct from glucosyltransferase was being stimulated.