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Estructura cristalina de un fragmento N-terminal de la proteína B girasa del ADN
D B Wigley1, G J Davies, E J Dodson
1Department of Chemistry, York University, Heslington, UK.
Nature
|June 20, 1991
Resumen
Los investigadores resolvieron la estructura cristalina del fragmento de proteína B girasa de ADN de Escherichia coli. Esto revela nuevos pliegues de proteínas y una estructura de dímeros crucial para la unión de ATP y el superenrolamiento del ADN.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Biología Estructural Biología estructural.
- Biología Molecular Biología Molecular
Sus antecedentes:
- La ADN girasa es esencial para la replicación y transcripción del ADN bacteriano.
- Comprender su estructura es clave para desarrollar nuevos antibióticos.
- La subunidad B de la ADN girasa se une e hidroliza el ATP.
Objetivo del estudio:
- Para determinar la estructura cristalina de un fragmento N-terminal de Escherichia coli ADN girasa B proteína.
- Para aclarar la base estructural de la unión y la hidrólisis de ATP.
- Para investigar el papel potencial en el superenrolamiento del ADN.
Principales métodos:
- Cristalografía de rayos X con una resolución de 2.5 A.
- Complejación con un análogo no hidrolizable del ATP.
Principales resultados:
- La estructura cristalina reveló un fragmento de dos dominios con nuevos pliegues de proteínas.
- El fragmento de proteína forma un dímero.
- Los dominios N-terminales están involucrados en la unión y la hidrólisis del ATP.
- Los dominios C-terminales crean un agujero central de 20 A.
Conclusiones:
- La estructura resuelta proporciona información sobre el mecanismo de unión de ATP e hidrólisis por la ADN girasa B.
- La interfaz del dímero y el agujero central sugieren un papel en el paso de la cadena de ADN durante el superenrolamiento.
- Esta información estructural puede guiar el diseño de nuevos agentes antibacterianos dirigidos a la ADN girasa.
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