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马丁尼3 脂翻转的限制

Ondřej Kroutil¹, Ladislav Bartoš^1,2, Ivo Kabelka¹

¹CEITEC-Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic.

Journal of chemical theory and computation

|September 25, 2025

概括

马蒂尼3力场低估了膜中的脂质翻转能量障碍,与马蒂尼2.2不同. 这影响了跨膜分子运输的模拟,这表明Martini 3需要对参数进行细化.

科学领域:

计算生物物理学的计算生物物理学
分子动力学模拟模型
膜生物物理学膜生物物理学

背景情况:

脂膜是重要的生物屏障,脂质的翻转是维护膜平衡和细胞功能至关重要的.
粗粒度 (CG) 力场,像马蒂尼力场一样,由于它们的效率和精度的平衡,对于模拟膜动态非常有价值.
最新的Martini 3力场对模拟脂翻转能量效应的准确性以前没有被评估.

研究的目的:

评估马丁尼3力场在描述脂翻转的自由能量障碍时的准确性.
为了将Martini 3的结果与较旧的Martini 2.2和CHARMM36m力场进行比较,以及全原子模拟.
为了确定马丁尼3的预测差异的潜在原因,并建议改进模型.

主要方法:

在POPC膜内对六种不同的脂 (POPC,DPPA,POPE,POPG,POPS,DPTAP) 进行了雨采样模拟.
使用Martini 3,Martini 2.2和CHARMM36m力场进行了模拟,并与全原子模拟进行了比较.
系统性参数测试用于调查特定力场参数对翻转式能量学的影响,特别是DPTAP.

主要成果:

与Martini 2.2和全原子模拟相比,Martini 3预测脂质翻转的自由能量障碍明显较低.
马丁尼3低估了翻转障碍,这对于具有正电荷的脂质DPTAP来说尤其严重.
在Martini 3中,胆和尾珠之间的改变的伦纳德-斯参数被确定为DPTAP差异的可能原因.

结论:

马丁尼3力场在准确参数化脂质翻转的能量方面存在局限性,特别是在带电的脂质中.
这些发现需要在使用Martini 3来模拟跨膜的分子运输时仔细考虑.
建议对Martini 3的参数化进行潜在的改进,以提高其对膜传输现象的准确性.

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