果蠅脂肪酸結合蛋白是脂肪酸結合蛋白家族之一員，屬於脂肪結合超蛋白家族;脂肪結合超蛋白家族是由一群可以與疏水性配基結合的小分子量蛋白所組成，與脂肪酸結合蛋白結合的是長鏈脂肪酸。在哺乳類中，脂肪酸結合蛋白表現量豐富並且具有組織特異性。脂肪酸結合蛋白在生理功能被認為是負責脂肪酸的輸送、代謝和儲存，參與能量儲存、細胞生長、細胞代謝等。脂肪酸結合蛋白對細胞膜的交互作用機制目前有兩種可能的機制被提出，分別是碰撞型機制和擴散型機制。在實驗室先前的研究中，已知果蠅脂肪酸結合蛋白的結構特徵和其配基的特異性。在研究文獻過去中指出純化脂肪酸結合蛋白質時即使已經過脫脂處理，還是容易含有從大腸桿菌來的內生性、疏水性汙染物。為了確保果蠅脂肪酸結合蛋白的純度，我們利用氣相層析確認取得的果蠅脂肪酸結合蛋白是純淨的，用這純淨的果蠅脂肪酸結合蛋白質做更進一步的實驗分析。加上，由於果蠅脂肪酸結合蛋白與細胞膜的交互作用機制尚未清楚。在這實驗中，我們使用核磁共振技術探討果蠅脂肪酸結合蛋白與細胞膜之間的交互作用。實驗發現沒有配基結合的果蠅脂肪酸結合蛋白與人造細胞膜的交互作用強，有配基結合的果蠅脂肪酸結合蛋白與人造細胞膜交互作用弱，這可能暗示人造細胞膜與沒有配基結合的果蠅脂肪酸蛋白會結合，但不太會結合有配基結合的果蠅脂肪酸蛋白。

Drosophila melanogaster fatty acid binding protein (dFABP) is one of fatty acid binding protein family which belongs to intracellular lipid binding protein superfamily, a group of low molecular weight proteins, which binds to long chain fatty acids. FABPs express highly in mammalian and have tissue specificity. Physiological function of FABPs are reported to transport, metabolize and store fatty acid involving in energy storage, cell growth, cellular metabolism and so on. There are two hypotheses for interaction between FABPs and membranes, diffusional-dependent mechanism and collisional-dependent mechanism. In our previous studies, we characterized structural properties and fatty acid binding specificity of dFABP. But mechanism between dFABP and membranes remains unknown. As reports, the purification of FABPs easily accompanied with hydrophobic contamination even though delipidation was conducted. To measure the purity of dFABP, we used gas chromatography in this study to confirm the apo form of dFABP we obtained for further studies. This study aims to obtain pure apo form dFABP and investigate the relationship between dFABP and membranes by liposome titration experiment of nuclear magnetic resonance spectroscopy (NMR). We found interaction between apo form dFABP and liposome is strong. But interaction between holo form dFABP and liposome is weak. Altogether, we suggested phospholipid vesicles associated with apo form dFABP, but disassociated with holo form dFABP.

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