Figure 6

Non-linear curve fitting of Rt (¹⁵ N/(¹⁵ N + ¹⁴ N)) against time (t) and estimation of t _1/2 . A: Algal cells were collected at 1, 4, 8, 16, 32, 64, and128 hr after transfer from ¹⁵N-medium to ¹⁴N-medium. Data points for several peptides for each protein at each time point are presented. The non-linear regression model was generated with the program CurveExpert. The Parameters were estimated with SAS. The data points for all three proteins were best fitted by the Weibull model, equation {y = a − β * e^{− γ * xθ}}. B: Three points are marked on the regression curve (a, b, and c). With respect to time, the point (a) designates the lower 95% confidence limit, and the point (c) designates the upper 95% confidence limit, of R_t equals to 50%. The 95% confidence interval of time when R_t equals 50% is estimated as: t_a ≤ t_1/2 ≤ t _c . This figure presented the RuBisCO data only. Similar analyses were performed for ATP synthase CF1 α and β subunits. Results for all three proteins are presented in Table 2.