Naowarojna Nathchar, Irani Seema, Hu Weiyao, Cheng Ronghai, Zhang Li, Li Xinhao, Chen Jiesheng, Zhang Yan Jessie, Liu Pinghua
Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States.
Department of Molecular Biosciences and Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, Texas 78712, United States.
ACS Catal. 2019 Aug 2;9(8):6955-6961. doi: 10.1021/acscatal.9b02054. Epub 2019 Jul 2.
Ergothioneine is a thiohistidine derivative with potential benefits on many aging-related diseases. The central step of aerobic ergothioneine biosynthesis is the oxidative C-S bond formation reaction catalyzed by mononuclear nonheme iron sulfoxide synthases (EgtB and Egt1). Thus far, only the EgtB (EgtB ) crystal structure is available, while the structural information for the more industrially attractive Egt1 enzyme is not. Herein, we reported the crystal structure of the ergothioneine sulfoxide synthase (EgtB ) from EgtB has both EgtB- and Egt1-type of activities. Guided by the structural information, we conducted Rosetta Enzyme Design calculations, and we biochemically demonstrated that EgtB can be engineered more toward Egt1-type of activity. This study provides information regarding the factors governing the substrate selectivity in Egt1- and EgtB-catalysis and lays the groundwork for future sulfoxide synthase engineering toward the development of an effective ergothioneine process through a synthetic biology approach.
麦角硫因是一种硫组氨酸衍生物，对许多与衰老相关的疾病具有潜在益处。有氧麦角硫因生物合成的核心步骤是由单核非血红素铁亚砜合酶（EgtB和Egt1）催化的氧化C-S键形成反应。到目前为止，只有EgtB（EgtB ）的晶体结构可用，而更具工业吸引力的Egt1酶的结构信息尚未可知。在此，我们报道了来自EgtB 的麦角硫因亚砜合酶（EgtB ）的晶体结构，EgtB 具有EgtB型和Egt1型活性。在结构信息的指导下，我们进行了Rosetta酶设计计算，并通过生物化学方法证明EgtB 可以更多地被改造为具有Egt1型活性。这项研究提供了有关Egt1和EgtB催化中底物选择性控制因素的信息，并为未来通过合成生物学方法开发有效的麦角硫因工艺而进行亚砜合酶工程奠定了基础。
