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Evidencia isotópica de la fijación biológica del nitrógeno por molibdeno-nitrogenasa de 3.2 Gyr
Eva E Stüeken1, Roger Buick1, Bradley M Guy2
1Department of Earth &Space Sciences and Astrobiology Program, University of Washington, Seattle, Washington 98195-1310, USA.
Nature
|February 18, 2015
Resumen
La fijación biológica del nitrógeno, crucial para la vida temprana, probablemente comenzó hace 3.200 millones de años. Esto sugiere que la disponibilidad de molibdeno en los antiguos océanos es anterior al Gran Evento de Oxidación.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- Biogeoquímica La biogeoquímica es la bioquímica.
- Ciencias de la Tierra Temprana Ciencias de la Tierra Temprana.
Sus antecedentes:
- El nitrógeno es esencial para la vida, pero las fuentes fijas de nitrógeno de la Tierra temprana pueden haber sido limitadas.
- Los procesos abióticos podrían producir nitrógeno fijo, pero probablemente en cantidades insuficientes para una gran biosfera.
- La evolución de la nitrogenasa, una enzima para la fijación biológica del nitrógeno, fue un paso crítico para la expansión de la vida.
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