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La nitrogenasa y la hidrogenasa libres de células de los nódulos de la raíz actinorrizal
Science (New York, N.Y.)
|August 17, 1979
Resumen
Los investigadores aislaron endófitos de actinomicetos de los nódulos de las raíces de alce. Estos endofitos produjeron una preparación libre de células con actividad de nitrogenasa y hidrogenasa de captación, lo que demuestra sus funciones biológicas.
Área de la Ciencia:
- Microbiología Microbiología.
- Interacciones entre plantas y microbios.
- La bioquímica es la bioquímica.
Sus antecedentes:
- Las plantas de Alder (Alnus glutinosa) albergan endófitos actinomicetos simbióticos en los nódulos de las raíces.
- Estos endofitos son cruciales para la fijación de nitrógeno en las plantas huésped.
- La comprensión de la maquinaria enzimática de estos endofitos es vital.
Objetivo del estudio:
- Para aislar y caracterizar las actividades enzimáticas de los endofitos del actinomiceto de los nódulos de la raíz del alce.
- Para investigar la presencia y la función de las enzimas nitrogenasa e hidrogenasa en una preparación libre de células.
Principales métodos:
- Disrupción de los nódulos de la raíz del alce en el nitrógeno líquido.
- Aislamiento de los endofitos del actinomiceto.
- Oscilación sónica leve para romper las células endofitas.
- Preparación de extractos libres de células para ensayos enzimáticos.
Principales resultados:
- Se obtuvo con éxito una preparación libre de células que contiene actividad nitrogenasa.
- Esta preparación demostró la capacidad de reducir el acetileno y los protones.
- También se identificó una hidrogenasa de captación libre de células en el preparado.
Conclusiones:
- Los endofitos del actinomycete de los nódulos de Alnus glutinosa poseen la nitrogenasa activa y absorben las enzimas de la hidrogenasa.
- Estas enzimas se pueden extraer y retener la actividad en un sistema libre de células.
- Este trabajo proporciona una base para futuros estudios bioquímicos de la fijación simbiótica del nitrógeno y el metabolismo del hidrógeno en los endofitos de los alces.
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