Pruebas espectroscópicas para los dos intermediarios de escisión de C-H de Aspergillus nidulans Isopenicilina N Sintasa
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Quantitative Analysis of Aspergillus nidulans Growth Rate using Live Microscopy and Open-Source Software
Published on: July 24, 2021
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Esta Tamanaha, Bo Zhang, Yisong Guo
1Max-Planck Institute for Chemical Energy Conversion , 45470 Mülheim a. d. Ruhr, Germany.
Journal of the American Chemical Society
|May 20, 2016
Resumen
La isopenicilina N sintasa (IPNS) utiliza hierro y oxígeno para formar la penicilina
Área de la Ciencia:
- La bioquímica
- Enzimología
- Química medicinal
Sus antecedentes:
- La isopenicilina N sintasa (IPNS) es crucial para sintetizar las estructuras del núcleo de la penicilina.
- Estudios previos establecieron un mecanismo de ciclización oxidativa de dos pasos para el IPNS.
- La naturaleza exacta de los intermediarios de hierro involucrados en la escisión de enlaces C-H seguía siendo difícil de alcanzar.
Objetivo del estudio:
- Identificar experimentalmente los intermediarios de hierro de alta valencia responsables de la escisión del enlace C-H durante la catálisis del IPNS.
- Para aclarar las estructuras geométricas y electrónicas de estos intermedios transitorios.
Principales métodos:
- Utilizó técnicas cinéticas y espectroscópicas de estado transitorio.
- Se utilizan sustratos etiquetados con deuterio (A[d2-C]V y AC[d8-V]) para el seguimiento de los intermedios de reacción.
- Combinación de datos experimentales con propuestas mecanicistas computacionales.
Principales resultados:
- Se han identificado dos compuestos intermedios distintos para la división de enlaces C-H.
- Caracterizó estos intermedios como especies Fe ((III) -superoxo y Fe ((IV) -oxo de alto espín.
- Los hallazgos experimentales se alinean con las predicciones computacionales anteriores.
Conclusiones:
- Proporcionó la primera evidencia experimental de las identidades de los intermediarios clave del hierro en la catálisis IPNS.
- Se confirmó el papel de las especies Fe ((III) -superoxo y Fe ((IV) -oxo de alto espín en la activación del enlace C-H.
- Avanzó la comprensión mecanicista de la biosíntesis de la penicilina.
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