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Dinámica mediada por protones de la transición conformacional alcalina del iso-1-citocromo c de la levadura
Robert E Martinez1, Bruce E Bowler
1Department of Chemistry and Biochemistry, University of Denver, 2190 East Iliff Avenue, Denver, Colorado 80208-2436, USA.
Journal of the American Chemical Society
|May 27, 2004
Resumen
La investigación de una Lys 73-->Su variante de iso-1-citocromo c reveló cómo mutaciones específicas alteran las transiciones conformacionales de las proteínas. Este estudio aclara el papel de los grupos ionizables en los mecanismos de plegamiento de las proteínas.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Dinámica de las proteínas Dinámica de las proteínas
- Biología molecular La biología molecular.
Sus antecedentes:
- El iso-1-citocromo c sufre una transición de conformación alcalina.
- Los grupos ionizables juegan un papel crítico en los cambios de conformación de las proteínas.
Objetivo del estudio:
- Para investigar la cinética de transición de conformación alcalina de una Lys 73-->Su variante de iso-1-citocromo c.
- Comprender el papel de los grupos gatillo ionizables en este cambio conformacional.
Principales métodos:
- Se utilizaron métodos de salto de pH para detener el flujo.
- Analizó la cinética de la transición conformacional alcalina.
Principales resultados:
- Su mutación desplazó la pK (a) del ligando Met 80 de ~10.5 a ~6.6.
- Dos grupos ionizables adicionales, además del ligando Met 80, fueron desenmascarados y modulan la cinética de la transición.
Conclusiones:
- Los equilibrios de ionización impactan significativamente en los mecanismos de plegamiento de las proteínas.
- El estudio proporciona información sobre la base molecular de las transiciones conformacionales de las proteínas.
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