Deletion of central alpha-helices in human apolipoprotein A-I: effect on phospholipid association

Mutants of the apolipoprotein A-I (apoA-I) prepared by deleting residues lying between positions 100 and 186 in the central alpha helices were studied as to their phospholipid binding activities. The results confirmed that the region from 100 to 186 is directly involved in the interactions of apoA-I with phospholipids, with the sequence 122-186 having a significant role in the initial association with the lipids while that of the region 100-121 takes care of making the complex stable.