A molecular theory of lipid—protein interactions in the plasma lipoproteins

Lipid—protein interaction in porcine high‐density (HDL3) lipoprotein

“…Our results do not support the suggestion of a specific electrostatic interaction between the zwitterionic phosphorylcholine group of lecithin and suitably arranged pairs of acidic and basic amino acid side chains of the protein [14]. Such an interaction would be expected to cause changes in molecular motion as well as chemical shift of the N(CHa)3 group not borne out by our n.m.r, experiments.…”

“…The peptide chains are largely present as c~-helices as evident from CD data [13] and our n.m.r, data suggest that the long axis of these helices are oriented approximately perpendicular to the axis of the hydrocarbon chains (cf. [9,14]). The conclusions derived for the native porcine HDL3 are corroborated by results obtained with a model system reconstituted from dimyristoyl lecithin and apoprotein.…”

“…[ 17] and X-ray small-angle scattering results [7] suggesting that the interaction of the protein with the phospholipids is confined to a rather narrow surface layer (10)(11)(12)(13)(14)(15) • ~ from X-ray scattering experiments) of the lipoprotein particle. The n.m.r, presented here do not warrant a discussion of the interaction and spatial arrangement of cholesterol and cholesteryl esters in HDL3.…”

Secondary structure of the cecropins: antibacterial peptides from the moth Hyalophora cecropia

“…It is shown that in dilute buffer solution cecropins A and B exist largely as random coil structures whereas in a hydrophobic environment they fold into more helical conformations. Prediction of secondary structure from sequence data according to Chou and Fasman [4,5] and model building strongly suggest that residues l-l 1 form what has been named an amphipathic helix [6] (Merrifield, Vizioli and Boman in preparation).…”

Sequence similarity between protein B and human apolipoprotein A‐IV

“…Because amphiphilic helical structures seem to be responsible for the lipid-binding properties of various proteins and peptides which interact with lipids or membrane surfaces [20][21][22][23], we examined the protein B sequence for segments with the potential to form amphiphilic helices. Secondary structure prediction of the N-terminal part of protein B according to Chou and Fasman [141 reveals the existence of four c~-helical segments ( fig.l).…”