林中生林明正Ming-Cheng醫學研究所2026-10-289999-12-312007https://handle.ncl.edu.tw/11296/z3ycnehttps://scholars.csmu.edu.tw/handle/123456789/35591研究目的：本篇研究是探討心血管藥物硝基化合物（nitro compounds）和脂肪酵素lipase活化性的關係。在試管內觀察硝基化合物和假單孢菌屬脂肪酵素（Pseudomonas species lipase,PSL）交互作用的特徵。實驗結果:苦酸PA及收斂酸styphnic acid的特性是PSL的混合型mixed-type抑制劑inhibitors。從化學結構觀點，PA及styphnic acid帶氫氧基hydroxyl讓這兩種硝基化合物具親水性（hydrophilic），所以PA及styphnic acid能進入lipase的hydrophilic active site親水催化反應位置，成為這酵素的抑制劑是因為這兩個化合物的親水性特徵。 另一方面，TNT，RDX，及HNIW是PSL基本（essential）的活化劑（activators），從化學結構的觀點，TNT，RDX，HNIW比PA及styphnic acid較具疏水性（hydrophobic），因此當TNT，RDX，HNIW混合活性界面劑triton-X 100結合到PSL的co-lipase結合位置binding site，而成為基本的PSL活化劑。 有趣的是HMX及硝化甘油既不是這酵素的抑制劑也不是活化劑，因HMX及硝化甘油的疏水性hydrophobic特徵，使它們並不結合到PSL的反應位置（active site）。有甘油主鏈的硝化甘油比起其他硝基化合物具有更穩定的構形（conformations），所以和界面活性劑作用較鬆弛。結論：本論文主要觀察，在硝基化合物中包括心血管藥物硝化甘油存在時，假單胞屬的脂肪酵素PSL催化水解對硝基苯丁酸酯（p-nitrophenyl butyrate） 在試管內的酵素動力學研究。依動力學來說PA 及 styphnic acid 是混合型的抑制劑，但TNT,RDX 及 HNIW 是基本的活化劑，有趣的是 HMX 及 硝化甘油既不是抑制劑也不是活化劑。Purpose : This dissertation embarks to understand the relationships between nitro compounds and the activation of lipase. Thus, the goal of this study is then to characterize interactions between nitro compounds and Pseudomonas Species lipase (PSL) in vitro.Results : PA and styphnic acid are characterized as the mixed-type inhibitors of PSL. From chemical structure point of view, PA and styphnic acid carry hydroxyl groups and make both compounds hydrophilic. Therefore, PA and styphnic acid are capable of entering the hydrophilic active site of Pseudomonas Species lipase and become inhibitors of the enzyme due to the hydrophilic character of both compounds. On the other hand, TNT, RDX, and HNIW are the essential activators of PSL. From chemical structure point of view, TNT, RDX, and HNIW are more hydrophobic than PA and styphnic acid. Therefore, TNT, RDX, and HNIW presumably mix with triton-X 100 and bind to the co-lipase binding site of PSL and become the essential activators of PSL. Moreover, the interfacial activation of PSL by the essential activators in the presence of detergents is proposed according to the lipase-colipase mechanism. Interestingly, HMX and nitroglycerin are neither an inhibitor nor an activator of the enzyme. Therefore, HMX and nitroglycerin do not bind to the active site of PSL due to the hydrophobic characters of HMX and nitroglycerin. Moreover, HMX does not bind to the co-lipase binding site of PSL probably due to a huge dimension of HMX and weak interactions between HMX and detergent triton X-100. With the glycerol backbone, nitroglycerin has more stable conformations than other nitro compounds and therefore it interacts loosely with the detergent.Conclusions :The goal of this work is to determine the enzyme kinetics for Pseudomonas Species lipase catalyzed hydrolysis of substrate p-nitrophenyl butyrate in the presence of nitro compounds such as nitroglycerin, 2,4,6-trinitrotoluene (TNT), picric acid, styphnic acid, hexahydro-1,3,5-trinitrotriazocine (RDX), octahydro-1,3,5,7-tetranitrotriazocine (HMX), and hexanitrohexaazaisowurtzitane (HNIW) in vitro. Kinetically, picric acid and styphnic acid are the mixed-type inhibitors but TNT, RDX, and HNIW are the essential activators of the enzyme in the presence of a detergent triton-X 100. Interestingly, HMX and nitroglycerin are neither an inhibitor nor an activator of the enzyme.thesis