植物非特異性脂質傳送蛋白 (Nonspecific lipid transfer proteins; nsLTPs) 是小分子量且帶正電的蛋白質，這一種蛋白質在 in vivo 中可以結合並且傳送脂質，依照分子量可以再將這一類蛋白質細分為兩小類，分別是分子量約 9 kDa 的 nsLTP1 以及分子量約 7 kDa 的 nsLTP2，從實驗解析出來的蛋白質結構中可以發現一個親脂性腔洞，以封閉或穿透的形式存在 nsLTPs 中，和脂質結合狀態下的 nsLTPs 分子結構亦被解析到原子等級的解析度，從這些結構中可以發現一個或兩個脂質分子位於親脂性腔洞中，目前對於 nsLTPs 分子結構的瞭解僅來自於這些經實驗解析出來平均結構，然而蛋白質及脂質之間的分子辨識是一個動態的過程，並且蛋白質的動態性質在結合脂質分子之後亦會有所改變，因此分子動力模擬 (Molecular dynamics simulation; MD simulation) 的技術是相當適合用來研究脂質所引起的蛋白質動態性質之改變，經由 MD simulations 以及針對其產生資料的分析，我們對 nsLTPs 的分子構形空間進行取樣，並詳細的描述這一蛋白質的詳細動態性質，更進一步我們利用了分子結合自由能的計算解釋了脂質分子的結合效應，在這篇研究報告中 MD simulation 的方法提供了其他實驗所難以達到的寶貴資訊。

Plant nonspecific lipid transfer proteins (nsLTPs) are small and positively charged proteins. This class of protein is notable for the ability to transfer lipid molecules in vitro. NsLTPs can be further divided into two subclasses according to their molecular weight, namely nsLTP1 (~9 kDa) and nsLTP2 (~7 kDa). Structures of nsLTPs in atomic resolution revealed that a hydrophobic cavity, either embedded in the interior or existed as a tunnel, can be found in this class of proteins. Structures of nsLTPs with one or two lipid molecules bound to the hydrophobic cavity were also solved to atomic resolution. Most understanding about the structural properties of plant nsLTPs were based on these static images. However, due to the fact that molecular recognition is a dynamical process and the binding of lipid molecules may also affect the dynamical behavior of nsLTPs. The techniques of molecular dynamics simulation are very suitable for the investigation of lipid-binding induced behavior changes. Through the molecular dynamics simulations and the following analyses, the conformational space of nsLTPs was sampled and the dynamical properties of the proteins were elaborated. More specifically, the effects of lipid molecule binding were also investigated by free energy calculation. The MD simulations thus provide insight into the structural dynamics which were difficult to achieve by other experimental procedures.

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