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El patrón de acetilación define la actividad de preparación de los tetrámeros de quitosano
Sven Basa1, Malathi Nampally1, Talita Honorato1
1University of Münster , Institute for Biology and Biotechnology of Plants , Schlossplatz 8 , 48143 Münster , Germany.
Journal of the American Chemical Society
|January 3, 2020
Resumen
El quitosano
Área de la Ciencia:
- La bioquímica
- Biología molecular
- Glicobiología
Sus antecedentes:
- La actividad biológica del quitosano está relacionada con su grado de polimerización (DP) y de acetilación (DA).
- La secuencia específica de unidades acetiladas y desacetiladas, conocida como patrón de acetilación (PA), también puede influir en la función del quitosano.
- La comprensión de la PA es crucial para elucidar el papel del quitosano como molécula portadora de información.
Objetivo del estudio:
- Investigar la influencia del patrón de acetilación (PA) en la actividad biológica de los oligosacáridos de quitosano.
- Determinar si el PA, además del DP y el DA, contribuye a las actividades de elicitor y priming del quitosano.
- Para establecer las quitosanas como moléculas portadoras de información de buena fe.
Principales métodos:
- Se prepararon oligosacáridos de quitosano parcialmente acetilados a partir de un polímero de quitosano de origen utilizando hidrolasas de quitosano recombinantes.
- Las mezclas de quitosano se fraccionaron por grado de polimerización (DP) en fracciones DP4-DP12.
- Se evaluaron las actividades de elicitor y de primado de las fracciones en células de arroz, incluidas las comparaciones de tetrámeros monoacetilados.
Principales resultados:
- Tanto las actividades de elicitor como las de primado de los oligosacáridos de quitosano fueron influenciadas por su grado de polimerización (DP).
- La actividad primaria también dependía del patrón de acetilación (PA), con secuencias específicas como ADDD+DADD que muestran una alta eficacia.
- Se observaron diferencias significativas en la actividad primaria entre los diferentes tetrámeros monoacetilados, lo que confirma el papel de la PA.
Conclusiones:
- El patrón de acetilación (PA) influye significativamente en la actividad biológica de los quitosanos, particularmente en la actividad primaria en las células de arroz.
- Los efectos biológicos del quitosano están determinados no sólo por el DP y el DA, sino también por la disposición específica de las unidades acetiladas.
- Este estudio establece las quitosanas como moléculas portadoras de información, siendo la PA un determinante clave de su función.
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