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Fotoconversión en la proteína fluorescente roja de la anémona de mar Entacmaea quadricolor: ¿está involucrada la
Davey C Loos1, Satoshi Habuchi, Cristina Flors
1Department of Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200F, 3001 Heverlee, Belgium.
Journal of the American Chemical Society
|May 11, 2006
Resumen
La isomerización cis-trans fotoinducida ocurre en la proteína fluorescente roja eqFP611.11. Este proceso, observado a través de la espectroscopia Raman, implica cambios en los cromóforos relacionados con la fluorescencia reducida y nuevas vías no radiativas.
Área de la Ciencia:
- La biofísica es la biofísica.
- Biología Molecular Biología Molecular
- La espectroscopia es una técnica de espectroscopia.
Sus antecedentes:
- Las proteínas fluorescentes verdes (GFP) son herramientas vitales en la investigación biológica.
- La isomerización de cromóforos está implicada en la desactivación no radiativa de las GFP.
- Las proteínas fluorescentes rojas (como DsRed y HcRed) comparten similitudes estructurales con eqFP611.
Objetivo del estudio:
- Para investigar la isomerización cis-trans fotoinducida en la proteína roja fluorescente eqFP611.11.
- Para aclarar el papel de la configuración de cromóforos en las propiedades fotofísicas de eqFP611.
- Para comparar los cambios inducidos por la foto en eqFP611 con otras proteínas fluorescentes rojas.
Principales métodos:
- Se empleó la espectroscopia Raman para estudiar los cambios fotoinducidos.
- Se utilizó la espectroscopia de absorción para controlar los cambios en la absorción de luz.
- El análisis de la estructura cristalina proporcionó información sobre la configuración de los cromóforos.
Principales resultados:
- La irradiación de eqFP611 con luz de 532 nm condujo a una disminución de la absorción a 559 nm.
- Se observó una disminución significativa en el rendimiento cuántico de fluorescencia y una cinética de desintegración alterada.
- Los espectros de Raman de eqFP611 irradiado mostraron similitudes con DsRed, lo que sugiere una isomerización trans-a-cis.
Conclusiones:
- Se observó una isomerización trans-a-cis fotoinducida del cromóforo en eqFP611.
- Esta isomerización está asociada con la aparición de nuevas vías de desintegración no radiativas.
- Los hallazgos contribuyen a la comprensión de la fotofísica de las proteínas fluorescentes rojas.
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