Figure 1.

Starch biosynthesis from [1-¹⁴C]Glc-6-P and [1-¹⁴C]Glc-1-P in experiments with ruptured (□) and intact (▪) potato tuber amyloplasts. Small amyloplasts were selected for the experiment. The amyloplasts were ruptured by treatment with 0.1% Triton X-100. The amyloplasts were incubated for 1 h with 4 mm exogenously added ATP and 3PGA and 2 mm metabolite (Glc-6-P or Glc-1-P) with 6.3 kBq [1-¹⁴C]Glc-6-P or [1-¹⁴C]Glc-1-P. The amount incorporated was normalized on the basis of the activity of AGPase in the plastid preparations. Each column represents a mean of three replicates. Each separate amyloplast preparation is numbered using roman numerals. U, Units.