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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
Published on: January 17, 2020
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Controles de la secuencia del sustrato Regioselectividad de la formación de la lationina por ProcM
Tung Le1, Kevin Jeanne Dit Fouque2, Miguel Santos-Fernandez2
1Department of Chemistry and Howard Hughes Medical Institute, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States.
Journal of the American Chemical Society
|November 1, 2021
Resumen
Las cianobacterias utilizan una sola enzima para crear diversos latipeptidos a partir de muchos péptidos precursores. Las secuencias de sustrato, no la enzima, dictan los patrones de enlace cruzado de la Lantionina, ayudando a futuros modelos de predicción.
Área de la Ciencia:
- La bioquímica
- Biología molecular
- Biología sintética
Sus antecedentes:
- Los lanthipéptidos son péptidos sintetizados por ribosoma y modificados post-traducionalmente (RiPP) cruciales para la estabilidad y la bioactividad.
- Las cianobacterias exhiben una biosíntesis combinatoria única, produciendo numerosos latipeptidos a partir de diversos péptidos precursores utilizando una sola lationina sintetasa.
- El mecanismo por el cual una sola enzima controla la ciclización para numerosos sustratos sigue sin estar claro.
Objetivo del estudio:
- Investigar los factores que rigen la regioselectividad de enlaces cruzados de la Lantionina en la biosíntesis de los Lantipéptidos cianobacterianos.
- Evaluar la espectrometría de movilidad de iones atrapados y la espectrometría de masas en tándem (TIMS-MS/MS) para la separación de isómeros de latipeptidos.
- Establecer una base para predecir los patrones de anillos de latipeptidos a partir de la biosíntesis combinatoria.
Principales métodos:
- Utilizó una biblioteca de variantes de péptidos precursores de ProcA3.3.
- Se utiliza la espectrometría de movilidad de iones atrapados-espectrometría de masas en tándem (TIMS-MS/MS) para la separación de isómeros.
- Secuencias de sustrato analizadas y actividad enzimática (ProcM).
Principales resultados:
- Las secuencias de péptidos del sustrato, en lugar de la enzima ProcM, determinan la regioselectividad de la formación de la tionina.
- TIMS-MS/MS separó efectivamente los isómeros constitucionales del latipeptídeo, superando el rendimiento de la cromatografía líquida convencional.
- Se identificaron factores clave para el resultado de la ciclización, pero no se encontraron reglas predictivas simples para todas las secuencias.
Conclusiones:
- La ciclización de lanthipéptido en cianobacterias es principalmente dependiente del sustrato.
- TIMS-MS/MS es una herramienta valiosa para el análisis de mezclas de latipeptídeos complejos.
- Se pueden desarrollar futuros modelos de aprendizaje profundo para predecir patrones de anillos de latipeptídeos en la biosíntesis combinatoria.
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