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Una estructura de giro inverso inducida por un dimero de ácido D, L-alfa-aminoxi de ácido D, L

Dan Yang¹, Jin Qu, Wei Li

¹Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P.R. China. yangdan@hku.hk

Journal of the American Chemical Society

|November 20, 2003

Resumen

Los péptidos lineales con dímeros de ácido D,L-alfa-aminoxi forman nuevas estructuras de bucle y giro inverso. Estos hallazgos avanzan en el diseño de péptidos al permitir restricciones conformacionales específicas.

Área de la Ciencia:

Química del péptido Química del péptido
Biología Estructural Biología estructural.
Química orgánica es la química orgánica.

Sus antecedentes:

Investigaciones anteriores demostraron que los ácidos D-alfa-aminoxi forman giros homoquirales N-O, produciendo estructuras helicoidales.
Los péptidos lineales que incorporan dímeros de ácido D, L-alfa-aminoxi fueron investigados en busca de nuevas propiedades conformacionales.

Objetivo del estudio:

Para explorar el comportamiento conformacional de péptidos lineales que contienen un segmento Dimer de ácido D, L-alfa-aminoxi.
Investigar el potencial de estos segmentos para restringir las estructuras secundarias de péptidos, específicamente las vueltas inversas.

Principales métodos:

Espectroscopia de resonancia magnética nuclear (RMN) (1D, 2D-NOESY, estudios de dilución).
Cristalografía de rayos X. Cristalografía de rayos X.
Cálculos de la mecánica cuántica.

Principales resultados:

El péptido 3, con un dímero de ácido D,L-alfa-aminoxi, adoptó una conformación de bucle con dos vueltas heteroquirales N-O.
Este segmento de bucle con éxito restringió los tetrapeptidos 4 y 6 en estructuras de giro inverso estabilizadas por un enlace de hidrógeno de anillo de 16 miembros.
El obstáculo estérico impidió la formación de un giro inverso en el tetrapeptido 5.
El análisis computacional reveló un nuevo giro inverso en la pentamida 7, con dos giros N-O heteroquirales y múltiples enlaces de hidrógeno.

Conclusiones:

Los dimeros de ácido D,L-alfa-aminoxi pueden inducir conformaciones específicas de bucle y de giro inverso en péptidos.
Estos hallazgos ofrecen nuevas estrategias para diseñar péptidos con estructuras secundarias definidas.
Se destaca la plasticidad conformacional de los péptidos que contienen ácido alfa-aminoxi.

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