Figure 4.

(A) Four sets of protection factors satisfying experimental constraints (color symbols) and reference protection factors (black circles). (B–E) Isotopic envelopes calculated for the protection factor sets in (A) are shown. The sets of protection factors closer to the exact ones (in orange and red) result in an isotopic envelope (C and D) closer to the exact one (black solid symbols). Circles, squares, and diamonds in (B–E) are used to indicate different time points. To see this figure in color, go online.