Download MendeleyCrystal structure of truncated human apolipoprotein A-I suggests a lipid-bound conformation.
Borhani, D.W., Rogers, D.P., Engler, J.A., Brouillette, C.G.(1997) Proc Natl Acad Sci U S A 94: 12291-12296
- PubMed: 9356442
- DOI: https://doi.org/10.1073/pnas.94.23.12291
- Primary Citation of Related Structures:
1AV1 - PubMed Abstract:
The structure of truncated human apolipoprotein A-I (apo A-I), the major protein component of high density lipoprotein, has been determined at 4-A resolution. The crystals comprise residues 44-243 (exon 4) of apo A-I, a fragment that binds to lipid similarly to intact apo A-I and that retains the lipid-bound conformation even in the absence of lipid. The molecule consists almost entirely of a pseudo-continuous, amphipathic alpha-helix that is punctuated by kinks at regularly spaced proline residues; it adopts a shape similar to a horseshoe of dimensions 125 x 80 x 40 A. Four molecules in the asymmetric unit associate via their hydrophobic faces to form an antiparallel four-helix bundle with an elliptical ring shape. Based on this structure, we propose a model for the structure of apo A-I bound to high density lipoprotein.
Organizational Affiliation:
Department of Organic Chemistry, Southern Research Institute, Birmingham, AL 35205, USA. borhani@sri.org
