Cofactor Biogenesis in Cysteamine Dioxygenase: C−F Bond Cleavage with Genetically Incorporated Unnatural Tyrosine
Cofactor Biogenesis in Cysteamine Dioxygenase: C−F Bond Cleavage with Genetically Incorporated Unnatural Tyrosine
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半胱胺双加氧酶中的辅因子生物发生：基因掺入的非天然酪氨酸导致 C–F 键断裂
DOI：
10.1002/ange.201803907
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发表时间：
2018
影响因子：
--
通讯作者：
Liu, Aimin
中科院分区：
文献类型：
--
作者：
Wang, Yifan;Griffith, Wendell P.;Li, Jiasong;Koto, Teruaki;Wherritt, Daniel J.;Fritz, Elizabeth;Liu, Aimin
半胱胺双加氧酶(ADO)是一种硫醇双加氧酶，其研究因其是否具有预期的蛋白质衍生辅因子而停滞不前。本文报道了人腺苷脱氢酶中一种半胱氨酸-酪氨酸辅因子的发现和鉴定，该辅因子通过硫醚(C-−，S)键在Cys220和Tyr222之间交联。通过将非天然氨基酸3，5-二氟酪氨酸(F2-TYR)特异性地掺入人ADO的Tyr222中，通过质谱学和19F 核磁共振谱鉴定了自催化氧化碳氟键的活化和氟的释放。这些结果表明，辅因子的生物合成是由一种强大的氧化剂在自催化过程中执行的。与半胱氨酸双加氧酶不同的是，这种交联会导致蛋白质的最小结构变化，并且不能用常规的低分辨率技术检测到。最后，提出了一个新的序列基序C-X-Y-Y(F)来识别Cys-Tyr交联链。
Cysteamine dioxygenase (ADO) is a thiol dioxygenase whose study has been stagnated by the ambiguity as to whether or not it possesses an anticipated protein‐derived cofactor. Reported herein is the discovery and elucidation of a Cys‐Tyr cofactor in human ADO, crosslinked between Cys220 and Tyr222 through a thioether (C−S) bond. By genetically incorporating an unnatural amino acid, 3,5‐difluoro‐tyrosine (F2‐Tyr), specifically into Tyr222 of human ADO, an autocatalytic oxidative carbon–fluorine bond activation and fluoride release were identified by mass spectrometry and19F NMR spectroscopy. These results suggest that the cofactor biogenesis is executed by a powerful oxidant during an autocatalytic process. Unlike that of cysteine dioxygenase, the crosslinking results in a minimal structural change of the protein and it is not detectable by routine low‐resolution techniques. Finally, a new sequence motif, C‐X‐Y‐Y(F), is proposed for identifying the Cys‐Tyr crosslink.