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Caracterización estructural de la penicidina A lantibiótica altamente ciclizada a través de una estrategia de
Christopher T Lohans1, Zedu Huang, Marco J van Belkum
1Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2.
Journal of the American Chemical Society
|November 22, 2012
Resumen
Los investigadores descubrieron la paenicidina A, un nuevo lantibiótico de Paenibacillus polymyxa. Este péptido antimicrobiano altamente ciclizado presenta seis enlaces cruzados de tioéter, lo que ofrece potencial para la preservación de alimentos y la terapéutica.
Área de la Ciencia:
- Microbiología Microbiología.
- La bioquímica es la bioquímica.
- Química del péptido Química del péptido
Sus antecedentes:
- Los antibióticos son péptidos antimicrobianos bacterianos con enlaces cruzados de tioéter, valiosos para la preservación de alimentos y la terapéutica.
- Paenibacillus polymyxa NRRL B-30509 produce antibióticos conocidos y un nuevo lantibiótico, la paenicidina A.
- Los informes anteriores de bacteriocina SRCAM 602 de esta cepa no estaban sustentados.
Objetivo del estudio:
- Para caracterizar el nuevo lantibiótico paenicidina A producido por Paenibacillus polymyxa.
- Para dilucidar las complejas conectividades de enlaces cruzados de tioéter de la paenicidina A.
- Evaluar la novedad estructural y las posibles aplicaciones de la paenicidina A.
Principales métodos:
- Aislamiento y purificación de la paenicidina A de Paenibacillus polymyxa NRRL B-30509.
- Estrategia novedosa de desulfurización/reducción parcial para el análisis de los enlaces de thioether.
- Espectrometría de masas en tándem (MS/MS) para el esclarecimiento estructural de conectividades de enlaces cruzados.
Principales resultados:
- Identificación y caracterización estructural de la paenicidina A, un nuevo lantibiótico.
- La Paenicidina A contiene seis anillos de Lantionina y Metilantionina, con tres anillos entrelazados.
- Un nuevo método determinó con éxito las conectividades de enlace cruzado del tioéter, superando las limitaciones de la RMN.
Conclusiones:
- La Paenicidina A representa un lantibiótico estructuralmente único y altamente ciclizado.
- La nueva estrategia de desulfurización / reducción de EM / EM es efectiva para estructuras lantibióticas complejas.
- La estructura única de la penicidina A justifica una mayor investigación para las aplicaciones antimicrobianas.
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