Fig. 2.

Characterization of total LDL at various stages of thermal denaturation. LDL sample under standard conditions was subjected to a T-jump from 4°C to 85°C, and LDL heat denaturation was monitored by turbidity (A). Aliquots of 40 μl taken at various time points are numbered from 0 (intact LDL) to 8 (fully denatured LDL). Each aliquot was diluted to 0.1 mg/ml protein and placed in a 1 mm path length cell to record a far-UV CD spectrum (B). The CD spectra of aliquots 0 (black dots), 1 (black line), and 2 (gray dots) fully overlapped. The major spectral changes observed at later stages of heat denaturation (numbered) are shown by the arrow. NDGE of LDL at various stages of heat denaturation (C). Lane numbers 0–8 correspond to aliquot numbers in panel A. St, molecular size standard; data for intact human VLDL (particle diameter 40–100 nm) are shown for comparison. Three major bands observed in the heat-denatured LDL are marked I–III.