The “beta-clasp” model of apolipoprotein A-I - A lipid-free solution structure determined by electron paramagnetic resonance spectroscopy

► Electron paramagnetic resonance spectroscopy was used to map apoA-I's structure. ► ApoA-I bears 4 beta strands, which may stabilize its lipid-free structure. ► The beta strands may organize the overall structure of apoA-I.