INTRODUCTION
An example of lipoprotein strucure determined by NMR is that of apolipoprotein C-I. ApoC-I is a 57 residue protein which is distributed mainly in HDL, and is an activator of the enzyme lecithin:cholesterol acyltransferase. Using NMR, the three-dimensional structure of apoC-I, was shown to consist of two lipid-binding amphipathic helical regions, residues alanine-7-to-isoleucine-29 and methionine-38-to-lysine-52, separated by a flexible linker, in the presence of sodium dodecyl sulfate used to model the lipoprotein environment. The N-terminal helix undergoes conformational exchange at a flexible hinge situated at leucine-11/lysine-12. The N-terminal helix binds less tightly to the detergent than the C-terminal helix as shown by its higher flexibility. We have also determined structures of apoC-I(7-24), apoC-I(35-53), and apoC-I(1-38), by NMR using sodium dodecyl sulfate (Rozek et al., 1995; 1997)1.
Protein Data Bank coordinates are also available. For details see Research Group section. Three-dimensional protein structures were calculated from NMR-derived distance data using the distance geometry program (Havel, 1991)2.
Two-dimensional proton NMR experiments were run on a Bruker AMX spectrometer operating at 600 MHz.
Created by Kathy Cushley
last modified: May 28,1998
URL: http://www.sfu.ca/~cushley