Genetic Incorporation of Selenotyrosine Significantly Improves Enzymatic Activity of Agrobacterium radiobacter Phosphotriesterase

Autor:	An Xiaojing, Jiangyun Wang, Dawei Zhang, Chao Chen, Aiping Huang, Tianyuan Wang, Ming-Jie Han
Rok vydání:	2021
Předmět:	chemistry.chemical_classification biology Chemistry Organic Chemistry Mutant Active site Biochemistry Enzyme assay Amino acid Phosphoric Triester Hydrolases Enzyme Agrobacterium tumefaciens biology.protein Molecular Medicine Enzyme kinetics Tyrosine Molecular Biology Agrobacterium radiobacter
Zdroj:	ChemBioChem.
ISSN:	1439-7633 1439-4227
DOI:	10.1002/cbic.202000460
Popis:	Tyrosine plays important roles in many enzymes. To facilitate enzyme design, mechanistic studies and minimize structural perturbation in the active site, here we report the genetic incorporation of a novel unnatural amino acid selenotyrosine (SeHF), which has single-atom replacement in comparison to tyrosine. The arPTE-(Agrobacterium radiobacter Phosphotriesterase) Tyr309SeHF mutant exhibits a significant 12-fold increase in kcat and 3.2-fold enhancement in kcat /KM at pH 7.0. Molecular dynamics simulations show that the SeHF309 mutation results in a conformational switch which opens up the product release pocket and increases the product release rate, thereby elevating the overall enzyme activity. Significant improvement of the catalytic efficiency at neutral pH by single unnatural amino acid (UAA) mutation broadens the application of this enzyme, and provides valuable insights to the mechanism. Our method represents a new approach for designing enzymes with enhanced activity.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::56d5b9102c512352cd1ebf8bcdbe8d56 https://doi.org/10.1002/cbic.202000460 Zobrazit plný text záznamu Plný text