Figure 2.

Combined online digestion by pepsin and nepenthesin I improves the HDX resolution. Comparison of peptide maps obtained by on-line proteolysis with nepenthesin-1 (green), pepsin (red), or their combination (blue) is projected on the FOXO4 sequence. In all cases, full sequence coverage was reached but pepsin/nepenthesin-1 digestion provided the highest redundancy and spatial resolution. Secondary structure elements are depicted above the sequence. The N-terminal region G₇₄–P₈₇ originates from the production plasmid and thus is not a part of the wild-type FOXO4 sequence (see also Figure S33 of Supplementary Materials).