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Un modelo químico para la regulación redox de la actividad de la proteína tirosina fosfatasa 1B (PTP1B)
Santhosh Sivaramakrishnan1, Kripa Keerthi, Kent S Gates
1Departments of Chemistry and Biochemistry, University of Missouri, Columbia, MO 65211, USA.
Journal of the American Chemical Society
|August 4, 2005
Resumen
El peróxido de hidrógeno (H2O2) regula las fosfatasas de proteínas. Un nuevo modelo revela que la inactivación oxidativa de la proteína tirosina fosfatasa 1B forma un enlace cruzado, lo que sugiere un mecanismo general de conmutación redox en las células.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Biología Molecular Biología Molecular
- La señalización celular.
Sus antecedentes:
- El peróxido de hidrógeno (H2O2) es una molécula de señalización endógena.
- El H2O2 regula la actividad de la proteína fosfatasa.
- La proteína tirosina fosfatasa 1B (PTP1B) está involucrada en la regulación redox.
Objetivo del estudio:
- Para investigar la regulación redox de PTP1B. para investigar la regulación redox de PTP1B. para investigar la regulación redox de PTP1B.
- Para modelar el sitio activo de PTP1B utilizando una pequeña molécula orgánica.
- Comprender el mecanismo de inactivación oxidativa de PTP1B.
Principales métodos:
- Cristalografía de rayos X con rayos X.
- Síntesis química de un compuesto modelo.
- Pruebas bioquímicas de ensayos.
Principales resultados:
- Se forma un nuevo enlace cruzado de proteínas intrastras durante la inactivación oxidativa de PTP1B.
- La oxidación de la cisteína del sitio activo al ácido sulfénico (RSOH) es un paso clave.
- El sistema de modelos confirmó la facilidad de la formación de enlaces cruzados.
Conclusiones:
- La formación de enlaces cruzados de proteínas oxidativas es un mecanismo general para la conmutación redox de la función de las proteínas.
- Esta química es relevante para la transducción de señales y el estrés oxidativo.
- La inactivación de PTP1B implica un enlace cruzado de cisteína a través de un intermediario de ácido sulfénico.
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