非專一性脂質運輸蛋白可以協助磷脂質、醣脂類、脂肪酸以及類固醇在細胞膜間的運輸，此蛋白質與脂質的結合具有廣泛的親和力。非專一性脂質運輸蛋白是植物中主要的脂質結合蛋白質，目前已從稻米、小麥、大麥、玉米、桃子以及杏仁中純化而出。本實驗決定了三種稻米非專一性脂質運輸蛋白複和物晶體結構，受質分別為荳蔻酸、棕櫚酸與硬脂酸。稻米非專一性脂質運輸蛋白複和物的整體結構是由四束螺旋折疊和一段長的羧基端loop組成，並在蛋白質的中央形成一疏水性空洞，此空洞提供了脂質結合的空間。稻米非專一性脂質運輸蛋白荳蔻酸與硬脂酸複和物中各含有一脂肪酸，但是稻米非專一性脂質運輸蛋白棕櫚酸複和物中含二條脂肪酸分子。第二條脂肪酸分子的結合與否可能是由脂肪酸分子與蛋白質分子的比例決定，當有足夠的脂肪酸分子時，疏水性空洞即可再容納第二條脂肪酸分子。羧基端loop具有相當的彈性使此蛋白質可以容納各式各樣的脂質分子。脂質分子主要藉由疏水性作用力和稻米非專一性脂質運輸蛋白的結合空洞結合；此外，脂質分子和蛋白質間的親水性作用力也可穩定蛋白質複和物。與脂質分子結合後，此蛋白質的結合空洞和羧基端loop有顯著的構象改變；然而，含一條和二條脂肪酸分子的蛋白質複和物間，構象差異並不大。

Nonspecific lipid transfer proteins (nsLTPs) facilitate the transfer of phospholipids, glycolipids, fatty acids, and steroids between membranes, with wide-ranging binding affinities. Three crystal structures of rice nsLTP1 from Oryza sativa, complexed with myristic (MYR), palmitic (PAL) and stearic acid (STE) were determined. The overall structures of the rice nsLTP1 complexes belong to the four-helix bundle folding with a long C-terminal loop. The nsLTP1-MYR and the nsLTP1-STE complexes bind a single fatty acid, while the nsLTP1-PAL complex binds two molecules of fatty acids. The C-terminal loop region is elastic in order to accommodate a diverse range of lipid molecules. The lipid molecules interact with the nsLTP1 binding cavity mainly through hydrophobic interactions. Significant conformational changes were observed in the binding cavity and the C-terminal loop of the rice nsLTP1 upon lipid binding.

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