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Un ciclo de metilaspartato en las haloarqueas.
Maria Khomyakova1, Özlem Bükmez, Lorenz K Thomas
1Mikrobiologie, Fakultät Biologie, Universität Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany.
Science (New York, N.Y.)
|January 22, 2011
Resumen
Las haloarqueas poseen una nueva vía metabólica para la asimilación del acetato, convirtiendo la acetil-coenzima A (acetil-CoA) en malato a través del metilaspartato. Este hallazgo amplía nuestra comprensión de la adaptación microbiana a nuevos nichos ecológicos.
Área de la Ciencia:
- El metabolismo microbiano es el metabolismo microbiano.
- La bioquímica es la bioquímica.
- Biología evolutiva Biología evolutiva.
Sus antecedentes:
- La adaptación de la vía metabólica es crucial para que los microbios entren en nuevos nichos ecológicos.
- El metabolismo central del carbono a menudo utiliza la acetil-coenzima A (acetil-CoA) para la conversión del sustrato.
- Anteriormente, solo se conocía la vía del ciclo glyoxilato y la vía del etilmalonil-CoA para la asimilación del acetil-CoA.
Objetivo del estudio:
- Identificar y caracterizar nuevas vías metabólicas para la asimilación de acetato en procariotas.
- Investigar los mecanismos por los cuales las haloarqueas se adaptan a nuevos entornos.
Principales métodos:
- Análisis de la vía metabólica.
- Pruebas de ensayos de enzimas.
- El análisis genómico del genoma.
Principales resultados:
- Las haloarqueas utilizan una tercera vía, hasta ahora desconocida, para la asimilación del acetil-CoA.
- Esta vía implica la oxidación del acetil-CoA a glyoxilato a través del intermediario metilaspartato.
- El ciclo concluye con la condensación del glyoxilato para formar malato, lo que requiere altas concentraciones intracelulares de glutamato y el acoplamiento del metabolismo del carbono y el nitrógeno.
Conclusiones:
- Se ha aclarado una nueva vía de asimilación de acetato en las haloarqueas.
- Esta vía destaca la innovación evolutiva a través de la integración de diversas reacciones metabólicas.
- Los hallazgos sugieren la transferencia génica lateral y el retoque metabólico en la evolución procariota.
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