FIG. 2.

Time dependence of product formation as monitored by the arabinase assay. Counts per minute is plotted instead of nanomoles of product, because the former more directly shows the sensitivity of the assay. Each data point is the average of three determinations, except for the data points at 0 and 5 min, which are averages of two determinations. Error bars, standard deviations. The amount of product (in nanomoles) is readily obtained by division of the counts per minute by the specific activity (for this particular preparation of [¹⁴C]AG, the specific activity of Ara₁₈ is 4,741).