本論文是以色胺酸對螢光團螢光淬滅的特性為基礎，設計並合成蛋白酶活性 感測器 FlAsH-3W2F-TCǶ利用一系列 FlAsH 螢光染料標示胜肽的螢光性質進行研究，發現帶有芳香環側鏈的胺基酸中，相較於阻胺酸與苯Ҙ胺酸，色胺酸對FlAsH 螢光染料的螢光有最好的淬滅效果；胜肽上的色胺酸數量越多對螢光的淬滅效果也越好Ƕ色胺酸對於螢光染料的淬滅是根據光誘發電子轉移，透過螢光分子與色胺酸之間碰撞所形成暫時的分子軌域，提供電子轉移的通道，使螢光團激發的能量得到鬆弛Ƕ在以 Trypsin 為模型的蛋白酶活性實驗中，感測器水解前後有將近 9 倍的螢光強度增加；在 Caspase-3 目標蛋白酶活性實驗中，也觀測到明顯的螢光增強Ƕ以色胺酸做為淬滅團在螢光感測器上的應用是可行的。;We synthesized a Caspase-3 sensor, FlAsH-3W2F-TC, whose fluorescence was quenched by tryptophan inside the peptidyl sensor backbone. By studying a series of FlAsH-labeled peptide sequences, tryptophan containing peptide sequence showed higher quenching ability than histidine and phenylalanine peptide sequences; the more tryptophan the peptide sequence contains, the higher quenching efficiency we get. The quenching phenomena is based on photo-induced electron transfer(PET). The excited fluorophore relax by conducting an electron through temporary collisional molecular orbital. In trypsin model experiment, our sensor showed ~9-fold fluorescence increasing after hydrolysis; in Caspase-3 experiment, our sensor also showed significant fluorescence increasing. Finally, the application of tryptophan as a natural quencher in peptidyl fluorescent sensor is feasible and potential.
