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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
Published on: January 17, 2020
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Conocimiento estructural y computacional del mecanismo catalítico de los mutantes de la hidrolasa de epóxido de
Zhoutong Sun1, Lian Wu2, Marco Bocola3,4
1Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences , 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin 300308, China.
Journal of the American Chemical Society
|December 13, 2017
Resumen
La evolución dirigida creó mutantes de la hidrolasa de epóxido de limoneno (LEH) para reacciones selectivas. Los datos computacionales y estructurales revelan por qué los mutantes procesan eficientemente el óxido de ciclohexeno pero no el óxido de ciclopenteno.
Área de la Ciencia:
- La bioquímica
- Ingeniería de enzimas
- Química computacional
Sus antecedentes:
- La hidrolasa de epóxido de limoneno (LEH) es crucial para las reacciones de desimetrización hidrolítica.
- La evolución dirigida ha producido mutantes con selectividad (R,R) y (S,S).
Objetivo del estudio:
- Para aclarar la base mecanicista de la selectividad del sustrato de los mutantes de LEH.
- Comprender por qué ciertas variantes de LEH procesan eficientemente el óxido de ciclohexeno pero no el óxido de ciclopenteno.
Principales métodos:
- Evolución dirigida de las LEH.
- Cristalografía de rayos X de complejos de enzima y sustrato.
- Extensos cálculos teóricos y cálculos de energía de activación.
Principales resultados:
- Los mutantes exhiben una alta enantioselectividad tanto para los productos (R,R) como para los (S,S).
- Las variantes de LEH convierten eficientemente el óxido de ciclohexeno pero no el óxido de ciclopenteno.
- El análisis computacional revela una alteración de la alineación entre nucleófilo y sustrato en las reacciones de óxido de ciclopenteno debido a la flexibilidad de la bolsa de unión.
Conclusiones:
- La flexibilidad de la enzima influye en la alineación del sustrato y los resultados de la reacción.
- Las ideas estructurales y computacionales guían la futura ingeniería de proteínas para diversos sustratos.
- La comprensión del mecanismo LEH proporciona un marco para el diseño de biocatalizadores selectivos.
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