一种新的磷脂分子膜界面分子动力学模拟

Molecular Dynamics Study of A New Lipids Bilayer Membrane

翻转磷脂分子是把中性磷脂分子的磷酸基团和胆碱基团的位置互换后人工合成的新磷脂分子。本文运用分子动力学方法研究磷脂的亲水带电基团在膜内不同位置时对膜界面的水分子的分布和结构的影响。结果发现翻转磷脂双层膜的磷酸基团周围水分子数目增加,而其胆碱基团周围水分子数目却是减少了。翻转磷脂膜界面的水分子平均偶极取向与自然的磷脂膜界面的水分子平均偶极取向是相反的,而与胆碱基团相关的水分子平均偶极取向也发生了逆向。

Inverted phospholipid is a new synthetic phospholipid molecule which switched the positions of phosphate group and choline group of natural phospholipid bilayer membrane.We used molecular dynamics method to investigate the effect of the switching the positions of hydrophilic charged groups of phospholipid membrane on the distribution and structure of water molecules at the interface.The results of simulations showed that the number of water molecules around the phosphate group increased,but the number of water molecules around the choline group decreased.There is also a significant change in the average dipole orientation of water molecules at inverted phospholipid membrane.It was found that the dipole orientation of water molecules near the same group at different phospholipid membrane also showed significant differences.