The Front Cover represents the discovery of a novel path during a scientist′s journey towards the biocatalytic incorporation of chlorine into L-proline. In their Communication, A. Papadopoulou et al describe the remodeling of an Fe/αKG hydroxylase into a halogenase utilizing the tools of protein engineering. By employing several rounds of directed evolution, a remodeled halogenase variant with a 98-fold improved apparent k_cat/K_m was generated. The reprogrammed biocatalyst is the first example of a stereo- and regioselective halogenase derivatizing L-proline at the C3 position and highlights the possibility to successfully access the diverse chemistries of Fe/αKG-dependent dioxygenases to expand the biocatalytic toolbox. More information can be found in the Communication by A. Papadopoulou et al.

中文翻译：

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封面：L-脯氨酸 cis-4-Hydroxylase 的重新编程和优化，用于其天然底物的 cis-3-卤化 (ChemCatChem 18/2021)

封面代表了科学家在将氯生物催化结合到L-脯氨酸的过程中发现了一条新途径。在他们的通讯中，A. Papadopoulou 等人描述了利用蛋白质工程工具将 Fe/αKG 羟化酶重塑为卤化酶。通过采用多轮定向进化，产生了表观k _cat / K _m提高 98 倍的重构卤化酶变体。重新编程的生物催化剂是立体和区域选择性卤化酶衍生L的第一个例子-脯氨酸位于 C3 位置，并突出了成功访问 Fe/αKG 依赖性双加氧酶的多种化学成分以扩展生物催化工具箱的可能性。更多信息可以在 A. Papadopoulou 等人的通讯中找到。