Nielsen M, Miao L, Ipsen J H, Jørgensen K, Zuckermann M J, Mouritsen O G
Department of Physics, McGill University, Montreal, Canada.
Biochim Biophys Acta. 1996 Sep 4;1283(2):170-6. doi: 10.1016/0005-2736(96)00086-7.
A recently discovered submain phase transition in multi-lamellar bilayers of long-chain saturated diacyl phosphatidylcholines (Jørgensen, K. (1995) Biochim. Biophys. Acta 1240, 111-114) is discussed in terms of a theoretical molecular interaction model using computer simulation techniques. The model interprets the transition to be due to a decoupling of the acyl-chain melting from the melting of the pseudo-two-dimensional crystalline lattice of the P beta' phase. A two-stage melting process is predicted by the calculations suggesting that the sub-main transition involves a lattice melting whereas the acyl-chain melting takes place at a higher temperature at the main transition. The calculated heat contents of the two transitions as well as the chain-length dependence compare favorably with experimental data for multi-lamellar phosphatidylcholine lipid bilayers.
利用计算机模拟技术，基于理论分子相互作用模型，对最近在长链饱和二酰基磷脂酰胆碱的多层双分子层中发现的亚主相转变（约根森，K.（1995年）《生物化学与生物物理学报》1240，111 - 114）进行了讨论。该模型将此转变解释为酰基链熔化与Pβ'相准二维晶格熔化的解耦。计算预测了一个两阶段熔化过程，表明亚主转变涉及晶格熔化，而酰基链熔化发生在主转变的更高温度下。两个转变的计算热含量以及链长依赖性与多层磷脂酰胆碱脂质双分子层的实验数据吻合良好。
