Figure 6.

HDX-MS of mature glucagon fibrils. Glucagon at 0.6 mg/mL was allowed to fibrillate and subjected to HDX. Deuterium uptake was measured by MS analysis following online pepsin digestion. Percent deuterium uptake for the three glucagon peptides in Peaks I′’ (black bars) and II′ (gray bars) following 48 h of HDX (n = 3, mean ± SD). Intensity of Peak II′ relative to Peak I′ (white bars) (i.e., [Peak II′ intensity/Peak I′ intensity] × 100) for the three peptic fragments following 48 h of HDX (n = 3, mean ± SD).