(Main panel) UV chromatographic profile of an SE-HPLC-SAXS analysis of hpHMW-FG (20 µl at 17.3 mg ml−1 in TBS were injected). (Inset) SDS/urea–PAGE analysis of the starting material (Inj.) and of the fractions collected on a duplicate run after disconnection from the SAXS setup (100 µl at ∼9 mg ml−1 were injected). Fractions are indicated at the bottom of the main panel. Their concentration was determined, and equal amounts (∼1.9 µg for fractions 2–7, but only ∼1.2 µg for fractions 1 and 8) of not-reduced samples were loaded in the wells of a 10 × 8 cm 1.5 mm-thick 3.2% T–5% C polyacrylamide SDS/urea gel, electrophoresed, stained with Coomassie blue and subjected to densitometric analyses (see Cardinali et al., 2010). The fractional concentrations of the two main bands expressed in % are reported at the bottom of each lane.