Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, School of Pharmacy, Shandong University , Jinan, Shandong 250012, China.
State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University , Jinan, Shandong 250100, China.
Anal Chem. 2017 May 2;89(9):4808-4816. doi: 10.1021/acs.analchem.6b03510. Epub 2017 Apr 13.
To enhance the efficiency of firefly luciferase/luciferin bioluminescence imaging, a series of N-cycloalkylaminoluciferins (cyaLucs) were developed by introducing lipophilic N-cycloalkylated substitutions. The experimental results demonstrate that these cyaLucs are effective substrates for native firefly luciferase (Fluc) and can produce elevated bioluminescent signals in vitro, in cellulo, and in vivo. It should be noted that, in animal studies, N-cyclobutylaminoluciferin (cybLuc) at 10 μM (0.1 mL), which is 0.01% of the standard dose of d-luciferin (dLuc) used in mouse imaging, can radiate 20-fold more bioluminescent light than d-luciferin (dLuc) or aminoluciferin (aLuc) at the same concentration. Longer in vivo emission imaging using cybLuc suggests that it can be used for long-time observation. Regarding the mechanism of cybLuc, our cocrystal structure data from firefly luciferase with oxidized cybLuc suggested that oxidized cybLuc fits into the same pocket as oxyluciferin. Most interestingly, our results demonstrate that the sensitivity of cybLuc in brain tumor imaging contributes to its extended application in deep tissues.
为了提高萤火虫荧光素酶/荧光素生物发光成像的效率，通过引入亲脂性的 N-环烷基取代基，开发了一系列 N-环烷基氨基荧光素（cyaLucs）。实验结果表明，这些 cyaLucs 是天然萤火虫荧光素酶（Fluc）的有效底物，可在体外、细胞内和体内产生增强的生物发光信号。值得注意的是，在动物研究中，10 μM（0.1 mL）的 N-环丁基氨基荧光素（cybLuc）（标准剂量的 d-荧光素（dLuc）的 0.01%）在相同浓度下比 d-荧光素（dLuc）或氨基荧光素（aLuc）辐射出 20 倍的生物发光。使用 cybLuc 进行更长时间的体内发射成像表明，它可以用于长时间观察。关于 cybLuc 的机制，我们从萤火虫荧光素酶与氧化 cybLuc 的共晶结构数据表明，氧化 cybLuc 适合与氧化荧光素结合在相同的口袋中。最有趣的是，我们的结果表明，cybLuc 在脑肿瘤成像中的灵敏度有助于其在深层组织中的扩展应用。
