Figure 2.

One N-terminal d-amino acid on LF_N-DTA enhances protein stability. (a) Translocation X-LF_N-DTA constructs was analyzed by protein synthesis inhibition assay in CHO-K1 cells after 6 h (n = 3). EC₅₀ values from the protein synthesis inhibition assay were graphed for all ^LX-LF_N-DTA or ^DX-LF_N-DTA constructs. EC₅₀ values (and error bars) were determined using a Boltzmann distribution fit. (b) ^LV-, ^DV-, ^LA-, ^DA-, ^LW-, and ^DW-LF_N-DTA_mut were translocated into CHO-K1 cells in the presence of 20 nM PA for 6 h, then extracted using digitonin lysis buffer, and analyzed by Western blot. As a proteasomal inhibitor, 20 μM lactacystin was used. Translocation of all ^LX-LF_N-DTA or ^DX-LF_N-DTA constructs was analyzed by Western blot.