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A Toolkit to Enable Hydrocarbon Conversion in Aqueous Environments
Published on: October 2, 2012
Dos moléculas de CO pueden unirse simultáneamente en el sitio de diirón de la NO reductasa de Bacillus azotoformans
Shen Lu1, Suharti, Simon de Vries
1Department of Environmental & Biomolecular Systems, OGI School of Science & Engineering, Oregon Health & Science University, Beaverton, OR 97006-8921, USA.
Journal of the American Chemical Society
|November 26, 2004
Resumen
Los estudios de resonancia Raman y FTIR revelan que el Bacillus azotoformans óxido nítrico reductasa forma dos complejos de CO. Esto apoya un mecanismo de catálisis de proximidad que implica la formación de dímeros de hierro-nitrosilo para la creación de enlaces N-N.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Enzimología Enzimología.
- La espectroscopia es una técnica de espectroscopia.
Sus antecedentes:
- Las enzimas reductasa de óxido nítrico (NOR) son cruciales en el ciclo del nitrógeno.
- La comprensión de los mecanismos NOR es clave para la respiración microbiana y la desnitrificación.
Objetivo del estudio:
- Para investigar los complejos de monóxido de carbono (CO) formados en la reducción de Bacillus azotoformans NOR.
- Para dilucidar la estructura del sitio activo y el mecanismo de reacción de NOR.
Principales métodos:
- Resonancia Espectroscopia Raman de resonancia Espectroscopia Raman de resonancia Espectroscopia Raman de resonancia Espectroscopia Raman de resonancia Espectroscopia Raman de resonancia
- Espectroscopia de infrarrojo con transformación de Fourier (FTIR)
- Estudios de temperatura criogénica en estudios de temperatura criogénica.
Principales resultados:
- Se identificaron dos bandas distintas de C-O en ~1970 cm-1 (hemo-CO) y ~2070 cm-1 (FeBCO no hemo).
- Se observó una configuración de hemo-CO semi-puente a temperaturas criogénicas, cambiando las frecuencias.
- La unión concomitante de dos moléculas de CO sugiere la formación de [{FeNO}7]2 dímeros de hierro-nitrosilo.
Conclusiones:
- Los hallazgos apoyan un mecanismo de catálisis de proximidad para NOR.
- La formación de dos grupos de hierro-nitrosilo facilita la formación de enlaces N-N durante la rotación del sustrato.
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