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Synthesis and Mass Spectrometry Analysis of Oligo-peptoids
Published on: February 21, 2018
Las vías de escisión de enlaces amídicos impulsadas por protones de los iones péptidos de fase gaseosa que carecen de
Benjamin J Bythell1, Sándor Suhai, Arpád Somogyi
1Department of Molecular Biophysics, Im Neuenheimer Feld 580, German Cancer Research Center, 69120 Heidelberg, Germany.
Journal of the American Chemical Society
|September 15, 2009
Resumen
La movilidad de los protones dicta la fragmentación de los péptidos. Nuevos mecanismos explican la formación de iones b e y en péptidos secuestrados por protones, cruciales para la proteómica. Esto avanza en la comprensión de las vías de disociación inducida por colisión (CID).
Área de la Ciencia:
- Espectrometría de masas por espectrometría de masas.
- La proteómica es la proteómica.
- La Dinámica Química es la Dinámica Química.
Sus antecedentes:
- El modelo de protones móviles explica la fragmentación de péptidos en la disociación inducida por colisión (CID).
- Diferencia los péptidos basados en la movilidad de los protones, influyendo en las vías de fragmentación.
- Los péptidos con protones secuestrados a menudo muestran formación de iones de secuencia limitada.
Objetivo del estudio:
- Para dilucidar los mecanismos de fragmentación de los iones péptidos con protones secuestrados.
- Para explicar la formación de iones b e y en estos casos difíciles.
- Presentar nuevas vías distintas del modelo clásico de la oxazolona.
Principales métodos:
- Análisis computacional de las escisiones de enlaces amídicos impulsadas por protones.
- Investigación de las vías de fragmentación de péptidos que carecen de protones fácilmente movilizables.
- Comparación de nuevos mecanismos con la vía establecida de la oxazolona.
Principales resultados:
- Se identificaron tres nuevos mecanismos de escisión de enlaces amídicos: el puente salino, el anhídrido y los intermediarios de imine enol.
- Estas nuevas vías son energéticamente menos exigentes que la vía clásica de la oxazolona.
- Proporciona una explicación mecanicista para la formación de iones b e y a partir de péptidos secuestrados por protones.
Conclusiones:
- La fragmentación de los péptidos secuestrados por protones ocurre a través de mecanismos distintos.
- Se proponen nuevas vías que involucran intermedios sal-puente, anhídrido e imine enol.
- Estos hallazgos son críticos para interpretar los datos proteómicos a gran escala.
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