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Reducciones quimioselectivas y selectivas del sitio catalizadas por un huésped supramolecular y un cofactor
Mariko Morimoto1, Wendy Cao1, Robert G Bergman1
1Chemical Sciences Division, Lawrence Berkeley National Laboratory and Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States.
Journal of the American Chemical Society
|January 20, 2021
Resumen
Los catalizadores supramoleculares permiten una modificación eficiente y selectiva de las biomoléculas en el agua. Este nuevo método permite el etiquetado específico del sitio de los péptidos y la insulina, imitando la actividad de la enzima.
Área de la Ciencia:
- Química supramolecular
- Catálisis
- La bioconjugación
Sus antecedentes:
- Las enzimas ofrecen una alta selectividad y aceleración de la velocidad para la modificación de biomoléculas en condiciones acuosas suaves.
- La catálisis supramolecular ha avanzado en la síntesis de moléculas pequeñas, pero está poco explorada para las biomoléculas complejas.
- La modificación quimioselectiva y selectiva del sitio de las biomoléculas es crucial para los estudios biológicos y terapéuticos.
Objetivo del estudio:
- Desarrollar un sistema supramolecular para la reducción eficiente y selectiva de varios grupos funcionales en condiciones acuosas básicas.
- Demostrar la modificación selectiva del sitio de las biomoléculas complejas, dirigida específicamente a los residuos de lisina.
- Aplicar este enfoque supramolecular para etiquetar péptidos y insulina humana en sitios específicos.
Principales métodos:
- Coencapsulación de piridina-borano con varios sustratos (enonas, cetonas, aldehídos, etc.) dentro de un huésped supramolecular.
- Aminación reductiva mediada por el huésped en condiciones acuosas básicas.
- Aplicación del sistema desarrollado a la lisina, los péptidos y la insulina humana sin protección.
Principales resultados:
- Se lograron reducciones eficientes de diversas moléculas en condiciones acuosas suaves y básicas.
- Se observó una excelente selectividad ε para la lisina no protegida, lo que demuestra una unión y reactividad diferenciadas de los huéspedes.
- Se logró con éxito el etiquetado selectivo de un solo residuo de lisina en un péptido de 11 aminoácidos e insulina humana.
Conclusiones:
- La catálisis supramolecular proporciona una poderosa plataforma para la modificación quimioselectiva y selectiva del sitio de las biomoléculas en medios acuosos.
- Este enfoque imita la selectividad enzimática y abre nuevas vías para la bioconjugación y la biología química.
- El método desarrollado ofrece una herramienta versátil para etiquetar objetivos biológicos complejos como péptidos y proteínas.
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