Molecular dynamics study of the structural characteristics of apoA-1 in double belt LL5 / 2 conformation and a bilayer containing DMPC and Cholesterol

MONGI S; LYNN S; PRIETO ED; GARDA HA; MCCARTHY A

Santiago del Estero

Congreso; XLIV Reunión Anual de la Sociedad Argentina de Biofísica (SAB); 2015

Sociedad Argentina de Biofísica (SAB)

Apolipoprotein A-I(apoA-I) is the major protein component of high-density lipoproteins (HDL). Thewell known antiatherogenic properties of HDL can be attributed, in part, totheir ability to remove cholesterol from peripheral tissues for transport toliver and steroidogenic tissues for metabolism and excretion. Various steps ofthis reverse cholesterol transport process depend on the functions of apoA-I.The primary sequence of apoA-I contains homologous repeating 11 and 22 aminoacid sequences that are known to form amphipathic lipid-binding helices. Innascient HDL particles, these helices form an outer shell, with thephospholipids and cholesterol forming a bilayer disk (1). In this work we usemolecular dynamics to compare the structural characteristics proposed by<Lynn et al>, which present two complete chains of apoA-1 in double beltLL5 / 2 conformation (2) and a bilayer containing 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) andCholesterol (3). References1-     TRICERRI, M. Alejandra, et al.Arrangement of apolipoprotein AI in reconstituted high-density lipoproteindisks: an alternative model based on fluorescence resonance energy transfer experiments. Biochemistry, 2001, vol. 40, no 16, p.5065-5074.2-     SILVA, RA Gangani D., et al. A massspectrometric determination of the conformation of dimeric apolipoprotein AI indiscoidal high density lipoproteins.Biochemistry,2005, vol. 44, no 24, p. 8600-8607.3-     WENNBERG, Christian L.; VAN DERSPOEL, David; HUB, Jochen S. Large influence of cholesterol on solutepartitioning into lipid membranes. Journalof the American Chemical Society, 2012, vol. 134, no 11, p. 5351-5361.