Effects of lipid composition and packing on the adsorption of apolipoprotein A-I to lipid monolayers

Journal Article · Tue Sep 06 00:00:00 EDT 1988 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00418a073· OSTI ID:6326410

Ibdah, J A; Phillips, M C

To better understand the factors controlling the binding of apolipoprotein molecules at the surfaces of serum lipoprotein particles, the adsorption of human apolipoprotein A-I to phospholipid monolayers has been studied. The influence of lipid packing was investigated by spreading the monolayers at various initial surface pressures (..pi../sub i/) and by using various types of lipid. The adsorption of /sup 14/C-methylated apolipoprotein A-I was monitored by simultaneously following the surface radioactivity and the change in surface pressure (..delta pi..). In general, increasing the ..pi../sub i/ of lipid monolayers reduces the adsorption of apolipoprotein A-I. The degree of adsorption of the apolipoprotein is also influenced by the physical state of the lipid monolayers. Addition of cholesterol generally decreases the adsorption of apolipoprotein A-I to egg PC monolayers. Analysis of the adsorption data suggests that the lateral compressibility of a lipid monolayer is a major determinant of the extent to which apolipoprotein A-I adsorbs. The protein penetrates into the interface to occupy space made available by the concomitant compression of phospholipid molecules so Gamma is higher for relatively compressible lipid monolayers. Lipid-protein interactions appear to influence the degree of adsorption to only a minor degree.

• Research Organization: Medical College of Pennsylvania, Philadelphia (USA)
• OSTI ID: 6326410
• Journal Information: Biochemistry; (United States), Vol. 27:18
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
APOLIPOPROTEINS
CROSS-LINKING
MEMBRANES
BIOPHYSICS
PHOSPHOLIPIDS
ADSORPTION
CARBON 14 COMPOUNDS
ISOTHERMS
SURFACE PROPERTIES
CHEMICAL REACTIONS
ESTERS
LABELLED COMPOUNDS
LIPIDS
LIPOPROTEINS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
POLYMERIZATION
PROTEINS
SORPTION
550201* - Biochemistry- Tracer Techniques