Various protein labeling methods based on the specific interactions between genetically encoded tags and synthetic probes have been proposed to complement fluorescent protein-based labeling. In particular, labeling methods based on enzyme reactions have been intensively developed by taking advantage of the highly specific interactions between enzymes and their substrates. In this approach, the peptides or proteins are genetically attached to the target proteins as a tag, and the various labels are then incorporated into the tags by enzyme reactions with the substrates carrying those labels. On the other hand, we have been developing an enzyme-based protein labeling system distinct from the existing ones. In our system, the substrate protein is attached to the target proteins as a tag, and the labels are incorporated into the tag by post-translational modification with an enzyme carrying those labels followed by tight complexation between the enzyme and the substrate protein. In this review, I summarize the enzyme-based protein labeling systems with a focus on several typical methods and then describe our labeling system based on tight complexation between the enzyme and the substrate protein.

中文翻译：

---

基于酶的蛋白质标记系统，用于对活细胞中的蛋白质进行位点特异性标记

已经提出了基于遗传编码标签和合成探针之间特定相互作用的各种蛋白质标记方法来补充基于荧光蛋白的标记。特别是，通过利用酶与其底物之间高度特异性的相互作用，已经深入开发了基于酶反应的标记方法。在这种方法中，肽或蛋白质作为标签通过基因连接到目标蛋白质上，然后通过酶反应将各种标签与带有这些标签的底物结合到标签中。另一方面，我们一直在开发一种与现有系统不同的基于酶的蛋白质标记系统。在我们的系统中，底物蛋白作为标签附着在目标蛋白上，并且通过使用携带这些标签的酶进行翻译后修饰，然后酶与底物蛋白质之间的紧密复合，将标签整合到标签中。在这篇综述中，我总结了基于酶的蛋白质标记系统，重点介绍了几种典型的方法，然后描述了我们基于酶和底物蛋白质之间紧密复合的标记系统。