Figure 5.

Deglycosylation of human CBG with Endo H reduces its steroid-binding affinity. (A) Western blot showing that fully glycosylated CBG and CBG N238 in concentrated and buffer-exchanged culture media from Lec1 CHO cells are completely deglycosylated after treatment with Endo H. Positions of molecular size markers (kDa) are indicated. (B) Representative Scatchard analyses showing that deglycosylation with Endo H leads to major decreases in cortisol-binding affinity (Kd), which were determined in two separate experiments for CBG (untreated, 0.8 nM and 0.5 nM vs Endo H-treated, 1.9 nM and 1.9 nM) and CBG N238 (untreated, 0.4 nM and 1.0 nM vs Endo H-treated, 4.2 nM and 4.8 nM).