Purification of Human APP695 and BACE1-454 and Activity Evaluation of BACE inhibitors

• Main Authors: Kai-Wei Lin, 林愷薇
• Other Authors: 孔繁璐
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/58304120481924396834

碩士 === 國立臺灣大學 === 藥學研究所 === 93 === β-site APP cleaving enzyme (BACE) participates in the rate-limiting step about Aβ production. It is an important target for BACE to treat AD. In order to characterize BACE catalyzed reaction by in vitro enzyme kinetic studies, establish a screening system to identity potential BACE inhibitors, and determine the inhibitory mechanism of potential BACE inhibitors, it is necessary to obtain large amounts of BACE and its substrate, APP695. Plasmids encoding the glutathione-S-transferase (GST)-APP fusion protein and GST-BACE (without the transmembrane domain) fusion protein were constructed and transformed into specific Escherichia coli strains to induce overexpression of the above fusion proteins. Protein purification was accomplished by affinity chromatography. Since the GST-BACE1-454 fusion protein overexpressed in Escherichia coli was found to form inclusion bodies, a denaturating/refolding approach was applied to obtain active BACE1-454. In the mean while, we used the fluorescence resonance energy transfer (FRET) assay system previously established in our laboratory to screen a series of compounds for potential BACE inhibitors.