Cis and trans unsaturated phosphatidylcholine bilayers: A molecular dynamics simulation study. (February 2016)

• Record Type: Journal Article
• Authors: Kulig, Waldemar; Pasenkiewicz-Gierula, Marta; Róg, T.
• Is Part Of: Chemistry and physics of lipids. Volume 195(2016)
• Page Start: 12
• Page End: 20
• Publication Date: 2016-02
• Subjects: Cholesterol -- OPLS-AA force field -- Torsional potential -- Model validation; Lipids -- Periodicals; Lipids -- Periodicals; Lipides -- Périodiques; Lipids; Periodicals; Electronic journals; 547.77
• DOI: 10.1016/j.chemphyslip.2015.07.002
• Languages: English
• ISSNs: 0009-3084

Abstract

Graphical abstract: Highlights: New force-field parameters were derived and validated for cis and trans unsaturated double bonds. Chains containing trans double bonds are more flexible due to the free rotation around saturated bonds next to the unsaturated one. Cholesterol affects trans unsaturated lipids more than cis unsaturated but less than saturated. Abstract: Trans unsaturated lipids are uncommon in nature. In the human diet, they occur as natural products of ruminal bacteria or from industrial food processing like hydrogenation of vegetable oils. Consumption of trans unsaturated lipids has been shown to have a negative influence on human health; in particular, the risk of cardiovascular disease is higher when the amount of trans unsaturated lipids in the diet is elevated. In this study, we first performed quantum mechanical calculations to specifically and accurately parameterize cis and trans mono-unsaturated lipids and subsequently validated the newly derived parameter set. Then, we carried out molecular dynamics (MD) simulations of lipid bilayers composed of cis or trans unsaturated lipids with and without cholesterol. Our results show that trans mono-unsaturated chains are more flexible than cis mono-unsaturated chains due to lower barriers for rotation around the single bonds next to the trans double bond than those next to the cis double bond. In effect, interactions between cholesterol and trans unsaturated chains are stronger than cis unsaturated chains, which results in a higher ordering effect of cholesterol in trans unsaturated bilayers.