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El amoníaco prebiótico procedente de la reducción del nitrito por el hierro (II) en la Tierra primitiva
1NASA-Ames Research Center, Moffett Field, California 94035, USA.
Nature
|October 14, 1993
Resumen
Tierra temprana de la Tierra temprana.
Área de la Ciencia:
- Química de los prebióticos.
- La geoquímica es la geoquímica.
- Los estudios sobre el origen de la vida.
Sus antecedentes:
- Los compuestos reducidos de nitrógeno son esenciales para el origen de la vida.
- La atmósfera de la Tierra primitiva era probablemente no reductora, produciendo óxidos de nitrógeno (NOx) a partir de descargas eléctricas.
- Los NOx habrían formado ácidos nítrico y nitroso, cayendo como lluvia ácida.
Objetivo del estudio:
- Investigar el potencial del hierro ferroso (Fe (II)) en la reducción de nitratos y nitritos a amoníaco.
- Explorar un mecanismo plausible para generar nitrógeno reducido en los primeros océanos.
Principales métodos:
- Simulación experimental de las condiciones prebióticas del agua de mar.
- Análisis de las reacciones químicas que involucran Fe (II), nitritos y nitratos.
Principales resultados:
- Fe (II) reduce efectivamente los nitritos y nitratos a amoníaco bajo condiciones específicas.
- El proceso es favorecido en el agua de mar con pH > 7.3.
- Las temperaturas más altas (por encima de 25°C) aumentan la velocidad de reacción.
Conclusiones:
- La oxidación de Fe (II) podría haber sido una fuente significativa de amoníaco prebiótico.
- Las condiciones geoquímicas específicas (pH, temperatura) fueron cruciales para esta vía de fijación del nitrógeno.
Palabras clave:
El ARC del Centro de la NASA en el Centro de la NASA.La disciplina de la NASA es la exobiología.Más Videos Relacionados
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