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La renalasa es una α-NAD(P) H oxidasa/anomerasa
Brett A Beaupre1, Brenton R Carmichael, Matthew R Hoag
1Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee , 3210 N. Cramer Street, Milwaukee, Wisconsin 53211-3209, United States.
Journal of the American Chemical Society
|August 23, 2013
Resumen
La renalasa, una hormona secretada por los riñones, se identifica como una α-NAD(P) H oxidasa/anomerasa, no una monoamina oxidasa. Esta nueva actividad enzimática implica catalizar una reacción de epimerización, una primicia en la fisiología de los mamíferos.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Enzimología Enzimología.
- Fisiología Fisiología Fisiología.
Sus antecedentes:
- La renalasa, una hormona proteica secretada por los riñones, influye en la presión arterial y la frecuencia cardíaca.
- Su papel propuesto como una monoamina oxidasa C, que oxida las catecolaminas, carecía de evidencia in vitro.
- La estructura de la renalasa se asemeja a las oxidasas, pero tiene un sitio activo único.
Objetivo del estudio:
- Para aclarar la verdadera función catalítica de la renalasa.
- Para investigar la actividad enzimática de la renalasa in vitro.
- Para identificar el sustrato y el mecanismo de reacción de renalase.
Principales métodos:
- Caracterización de la actividad enzimática de la renalasa.
- Investigación de los requisitos de cofactores y productos de reacción.
- Análisis cinético del proceso catalítico.
Principales resultados:
- La renalasa funciona como una α-NAD(P) H oxidasa/anomerasa.
- Utiliza bajas concentraciones de α-anomers de NADPH y NADH.
- La enzima reduce rápidamente su cofactor de flavina, reacciona con el dioxígeno, produce peróxido de hidrógeno y epimeriza el dinucleótido de nicotinamida.
Conclusiones:
- La función primaria de Renalase no es la actividad de la monoamina oxidasa.
- Este estudio revela una nueva actividad de las flavoproteínas: catalizar una reacción de epimerización.
- Los hallazgos resaltan la importancia fisiológica de las anomalías α-NAD(P) H que ocurren naturalmente.
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