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De la enzima suicida al catalizador: la transferencia de sulfuro dependiente del hierro en el Methanococcus
Bekir E Eser1, Xuan Zhang2, Prem K Chanani3
1Department of Medical Biochemistry, Emine-Bahaeddin Nakıboglu School of Medicine, Zirve University , Gaziantep 27260, Turkey.
Journal of the American Chemical Society
|March 2, 2016
Resumen
La tiazol sintasa de Methanococcus jannaschii utiliza sulfuro exógeno y es catalítica, a diferencia de las enzimas de levadura. Este estudio revela el mecanismo catalítico de la incorporación de azufre en la biosíntesis de tiamina.
Área de la Ciencia:
- La bioquímica
- Microbiología
- Enzimología
Sus antecedentes:
- La incorporación de azufre en la biosíntesis de tiamina tiazol difiere entre las bacterias y las levaduras.
- La tiazol sintasa de levadura (THI4p) es una enzima de conversión única que utiliza una cisteína del sitio activo para el sulfuro.
- La incorporación de azufre bacteriano involucra proteínas tiocarboxiladas.
Objetivo del estudio:
- Investigar el mecanismo de transferencia de azufre en la biosíntesis de tiamina tiazol por el Methanococcus jannaschii Thi4 ortholog.
- Para determinar si la enzima de M. jannaschii es catalítica y utiliza sulfuro exógeno.
Principales métodos:
- Estudios estructurales de la enzima M. jannaschii Thi4.
- Ensayos bioquímicos para elucidar los mecanismos de transferencia de sulfuro.
Principales resultados:
- El ortholog Thi4 de Methanococcus jannaschii utiliza sulfuro exógeno como fuente de azufre.
- Esta enzima arqueal funciona de manera catalítica, a diferencia de la levadura THI4p.
- Los datos estructurales y bioquímicos proporcionan información mecanicista sobre las reacciones de transferencia de sulfuro.
Conclusiones:
- Methanococcus jannaschii Thi4 representa una estrategia catalítica distinta para la biosíntesis de la tiamina tiazol.
- Comprender esta enzima arqueal avanza el conocimiento del metabolismo del azufre y los mecanismos enzimáticos.
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