Vista atómica de la ciclosporina A acuosa: desentrañar un misterio de décadas de antigüedad
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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
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Miranda N Limbach1, Aleksandra Antevska1, Damilola S Oluwatoba1
1Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States.
Journal of the American Chemical Society
|July 5, 2022
Resumen
Los investigadores revelan la estructura atómica de la ciclosporina A (CycA) en el agua, identificando un nuevo conformador (A1) crucial para comprender su actividad biológica y las interacciones de la membrana.
Área de la Ciencia:
- Biología estructural
- La bioquímica
- Farmacología
Sus antecedentes:
- La ciclosporina A (CycA) es un fármaco inmunosupresor vital.
- La determinación de la conformación de CycA en soluciones acuosas ha sido un desafío debido a su baja solubilidad en agua.
Objetivo del estudio:
- Elucidar la estructura a nivel atómico de la ciclosporina A libre en un medio acuoso.
- Caracterizar las nuevas conformaciones de CycA y su estabilidad.
Principales métodos:
- Combinación de rayos X y difracción de neutrones de un solo cristal.
- Experimentos de espectroscopia y titulación por resonancia magnética nuclear (RMN).
Principales resultados:
- Se resolvió un conformador único (A1) con un nuevo enlace cis-amida y dos ligandos de agua.
- El conformador A1 es abundante en mezclas acuosas de metanol, comparable a la forma cerrada.
- Se identificaron cinco conformadores adicionales, incluido uno con dos amidas cis.
Conclusiones:
- El estudio proporciona una visión atómica de la conformación acuosa de CycA, revelando un nuevo conformador estable.
- Estos hallazgos mejoran la comprensión de la permeabilidad de la membrana análoga de CycA y las interacciones con el fármaco objetivo.
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