title: UC/MALDI-MS analysis of HDL; evidence for density-dependent post-translational modifications.
abstract: The purpose of this study is to determine whether the nature of the post-translational modifications of the major apolipoproteins of HDL is different for density-distinct subclasses. These subclasses were separated by ultracentrifugation using a novel density-forming solute to yield a high-resolution separation. The serum of two subjects, a control with a normolipidemic profile and a subject with diagnosed cardiovascular disease, was studied. Aliquots of three HDL subclasses were analyzed by MALDI and considerable differences were seen when comparing density-distinct subclasses and also when comparing the two subjects. A detailed analysis of the post-translational modification pattern of apoA-1 shows evidence of considerable protease activity, particularly in the more dense fractions. We conclude that part of the heterogeneity of the population of HDL particles is due to density-dependent protease activity.
authors.affiliation: Department of Chemistry Texas A&M University, College Station, Texas, 77843-3255, U.S.A.
authors.forename: Jeffery D
authors.initials: JD
authors.lastname: Johnson
authors.forename: Ronald R
authors.initials: RR
authors.lastname: Henriquez
authors.forename: Shane E
authors.initials: SE
authors.lastname: Tichy
authors.forename: David H
authors.initials: DH
authors.lastname: Russell
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: McNeal
authors.forename: Ronald D
authors.initials: RD
authors.lastname: Macfarlane