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Fluorescence Biomembrane Force Probe: Concurrent Quantitation of Receptor-ligand Kinetics and Binding-induced Intracellular Signaling on a Single Cell
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Una molécula de bloqueo automático que funciona con una llave fotorresponsiva
Takahiro Muraoka1, Kazushi Kinbara, Takuzo Aida
1Department of Chemistry and Biotechnology, School of Engineering, and Center for NanoBio Integration, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Journal of the American Chemical Society
|August 31, 2006
Resumen
Este estudio demuestra un mecanismo de auto-bloqueo reversible en un huésped molecular. El anfitrión es el anfitrión.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Coordinación Química de la Coordinación
- La fotoquímica es la fotoquímica.
Sus antecedentes:
- El anfitrión rotativo 1 presenta una unidad de ferroceno y está conformativamente bloqueado a través de la coordinación intramolecular Zn-N.
- Este bloqueo interno ocurre en disolventes apolares entre las unidades de zinc porfirina y anilina.
Objetivo del estudio:
- Para investigar las interacciones huésped-huésped entre el huésped rotativo 1 y los isómeros de 1,2-bispiridiletileno (2).
- Para demostrar una operación de auto-bloqueo reversible controlada por isomerización fotoquímica.
Principales métodos:
- Utilizó espectroscopia de dicroísmo circular (CD) para visualizar cambios conformacionales.
- Empleó isómeros cis y trans de 1,2-bispiridiletileno (cis-2 y trans-2) como invitados.
- Investigó la isomerización fotoquímica de la molécula huésped para controlar el estado de bloqueo del huésped.
Principales resultados:
- El isómero cis (cis-2) rompe fácilmente los enlaces de coordinación internos del huésped, formando un complejo bloqueado externamente.
- El isómero trans (trans-2) no interrumpe el bloqueo interno, mostrando una afinidad de unión diferencial.
- La isomerización fotoquímica de cis-2 a trans-2 libera al huésped y restaura la cerradura interna.
- La isomerización fotoquímica de trans-2 a cis-2 en presencia del huésped induce el bloqueo externo.
Conclusiones:
- Demostró una operación de auto-bloqueo reversible en un sistema molecular.
- Destacó el papel crucial del isomerismo invitado y el control fotoquímico en el ensamblaje supramolecular.
- Mostró el potencial de las máquinas y interruptores moleculares sensibles a la luz.
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