Due to advances in methods for site-specific incorporation of unnatural amino acids (UAAs) into proteins, a large number of UAAs with tailored chemical and/or physical properties have been developed and used in a wide array of biological applications. In particular, UAAs with specific spectroscopic characteristics can be used as external reporters to produce additional signals, hence increasing the information content obtainable in protein spectroscopic and/or imaging measurements. In this Review, we summarize the progress in the past two decades in the development of such UAAs and their applications in biological spectroscopy and microscopy, with a focus on UAAs that can be used as site-specific vibrational, fluorescence, electron paramagnetic resonance (EPR), or nuclear magnetic resonance (NMR) probes. Wherever applicable, we also discuss future directions.

中文翻译：

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用于生物光谱学和显微镜学的非天然氨基酸


由于将非天然氨基酸 (UAA) 定点掺入蛋白质的方法取得了进步，大量具有定制化学和/或物理特性的 UAA 已被开发出来并用于广泛的生物应用。特别是，具有特定光谱特性的 UAA 可以用作外部报告基因来产生额外的信号，从而增加蛋白质光谱和/或成像测量中可获得的信息内容。在这篇综述中，我们总结了过去二十年此类UAA的发展及其在生物光谱和显微镜中的应用的进展，重点是可用作位点特异性振动、荧光、电子顺磁共振（EPR）的UAA。 ），或核磁共振（NMR）探针。在适用的情况下，我们还会讨论未来的方向。