Structure and conformational analysis of lipid-associating peptides of apolipoprotein B-100 produced by trypsinolysis. Academic Article uri icon

Overview

abstract

  • Apolipoprotein B-100 (apo B-100) contains putative lipid-associating regions that are, in part, responsible for its overall structure in human plasma low-density lipoproteins. Some of these regions have been identified by reassembly of the total tryptic peptides of apo B-100 with bovine brain sphingomyelin, 1-palmitoyl-2-oleoyl phosphatidylcholine (POPC) and dimyristoylphosphatidylcholine (DPMC). Although more than 500 tryptic peptides are predicted from the known number of arginines and lysines in apo B-100, significant amounts of only 13 peptides spontaneously associate with all three phospholipids. These peptides share some structural characteristics, as predicted by several algorithms, that distinguish them from the water-soluble apolipoproteins. Most apolipoproteins associate with lipids via amphipathic helices and are highly helical in native and reassembled lipoproteins. Analysis of all apo B-100 lipophilic peptides by circular dichroism and by use of a predictive algorithm reveals no evidence of amphipathic helices. Although the predictive algorithm suggested that the lipophilic peptides of apo B-100 contain the sequence determinants for beta-sheet, no spectroscopic evidence for this structure was found. We conclude that the lipophilic regions of apo B-100 liberated by trypsinolysis are highly hydrophobic, although their secondary structures do not fit any simple model.

publication date

  • December 1, 1989

Research

keywords

  • Apolipoproteins B
  • Lipid Metabolism
  • Peptide Fragments
  • Trypsin

Identity

Scopus Document Identifier

  • 0024916340

Digital Object Identifier (DOI)

  • 10.1007/BF01024895

PubMed ID

  • 2624682

Additional Document Info

volume

  • 8

issue

  • 6