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Updated: Jan 31, 2026
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A Fast and Quantitative Method for Post-translational Modification and Variant Enabled Mapping of Peptides to Genomes
Published on: May 22, 2018
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La proteómica química revela la regulación de las hidrolasas de las sales biliares a través de modificaciones
Amy K Bracken1, Kien P Malarney2, Pamela V Chang1,3,4,5,6
1Department of Chemistry and Chemical Biology, Cornell University, 162 Sciences Dr.,Ithaca, New York 14853, United States.
Journal of the American Chemical Society
|January 29, 2026
Resumen
Las bacterias intestinales regulan el metabolismo de los ácidos biliares a través de la actividad de la enzima hidrolasa de sales biliares (BSH). Descubrimos que la oxidación reversible de la cisteína del sitio activo de la BSH inactiva la enzima, proporcionando un nuevo mecanismo regulador.
Área de la Ciencia:
- Microbiología Microbiología.
- La bioquímica es la bioquímica.
- Enzimología Enzimología.
Sus antecedentes:
- El microbioma intestinal metaboliza los ácidos biliares en moléculas de señalización.
- La hidrolasa de sal biliar (BSH) es clave para este proceso, pero su regulación no está clara.
Objetivo del estudio:
- Investigar la regulación de la actividad de la hidrolasa de sales biliares (BSH).
- Identificar las nuevas modificaciones post-traduccionales que afectan la función de BSH.
Principales métodos:
- Utilizó una plataforma quimioproteómica con una nueva sonda de ácido biliar.
- Los estados de oxidación de cisteína analizados en los sitios activos de BSH.
- Modificaciones perfiladas de BSH en todo el microbioma intestinal.
Principales resultados:
- Se identificó la oxidación reversible de la cisteína (formación de ácido sulfénico) en el sitio activo de la HBS.
- Se demostró que este estado de oxidación (Cys-SOH) inactiva la actividad catalítica de BSH.
- Se observó que algunas enzimas BSH intestinales se inactivan de manera reversible a través de la oxidación Cys2.
Conclusiones:
- La oxidación reversible de la cisteína del sitio activo de la BSH es un nuevo mecanismo para la regulación enzimática.
- Esta oxidación proporciona una forma de controlar el metabolismo de los ácidos biliares en respuesta a los cambios fisiológicos.
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