Fig. 2.

Analysis of ¹⁵N incorporation into peptides of specific Arabidopsis cell culture proteins. A, examples of theoretical prediction and actual MS fit at 0, 24, 96, and 168 h (theoretical prediction, red; actual, blue) for single peptides derived from MAB1 (At5g50850) and TRIP-1 (At2g46280). B, histogram of calculated ¹⁵N partial labeling averages for peptides at 24, 96, and 168 h following ¹⁵N addition. In total, 336, 381, and 344 peptides are used for the distributions at each time point. C, average ratio of ¹⁴N only (NA) to ¹⁵N containing (H) + ¹⁴N only peptides (NA/(H + NA)) for all the MAB1 and TRIP-1 peptides at 24, 96, and 168 h. The error bars show the standard deviation.