Figure 2.

MCCase activity and the accumulation of the biotin-containing subunit of MCCase in soybean seedlings at 13 DAP. A, Organs of a soybean seedling. B, MCCase activity (mean of five experiments ± se). C, Western blot probed with antiserum to detect the biotin-containing subunit of MCCase. D, Western blot identical to that shown in C, but instead probed with ¹²⁵I-streptavidin to detect the biotin prosthetic group on the biotin-containing subunit of MCCase. In C and D protein samples were loaded on the basis of equal MCCase activity (0.1 nmol/min) to detect differences in the catalytic efficiency of the enzyme among organs. The data presented in C and D were gathered from a single experiment; five replicates of this experiment gave similar results.