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Hidroxilación regioselectiva y enantioselectiva de alcano con citocromos P450 BM-3 diseñados por ingeniería
Matthew W Peters1, Peter Meinhold, Anton Glieder
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|October 30, 2003
Resumen
Las enzimas de Bacillus megaterium citocromo P450 BM-3 diseñadas para hidroxilar selectivamente los alcanos lineales. Estos biocatalizadores demuestran una alta actividad y enantioselectividad en sistemas de células enteras.
Área de la Ciencia:
- La biocatálisis por biocatálisis.
- Ingeniería de enzimas Ingeniería de enzimas Ingeniería de enzimas
- Química orgánica es la química orgánica.
Sus antecedentes:
- El citocromo P450 BM-3 (CYP102A1) de Bacillus megaterium es una enzima muy potente.
- La ingeniería de P450 para la hidroxilación selectiva de alcano es crucial para la química verde.
- Los métodos anteriores a menudo carecen de regionalidad y enantioselectividad.
Objetivo del estudio:
- Para diseñar el citocromo P450 de Bacillus megaterium BM-3 para la hidroxilación selectiva de alcano.
- Para lograr una alta regioselectividad y enantioselectividad utilizando oxígeno atmosférico.
- Para demostrar la utilidad de los P450 modificados en las biotransformaciones de células enteras.
Principales métodos:
- La evolución dirigida y la mutagénesis dirigida en el sitio se emplearon para modificar P450 BM-3.
- Las reacciones de hidroxilación de alcanos se realizaron utilizando variantes de enzimas de ingeniería.
- Se llevaron a cabo biotransformaciones de células enteras utilizando Escherichia coli que expresa P450 modificados por ingeniería.
Principales resultados:
- Variante 9-10A-A328V de octano hidroxilado a S-2-octanol con un 40% de exceso enantiomérico (ee).
- Variante 1-12G de alcanos hidroxilados (>hexano) a R-2-alcoholes con 40-55% ee.
- Los biocatalizadores de ingeniería exhibieron una alta actividad (hasta 400 min-1) y estabilidad.
Conclusiones:
- Las variantes modificadas de P450 BM-3 proporcionan hidroxilación regio y enantioselectiva de alcanos lineales.
- Estos biocatalizadores mantienen la selectividad en sistemas de expresión de alto nivel como E. coli.
- Las enzimas desarrolladas ofrecen una ruta sostenible para la producción de alcoholes quirales.
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