Transglycosylation by a chitinase from Enterobacter cloacae subsp. cloacae generates longer chitin oligosaccharides

Abstract Humans have exploited natural resources for a variety of applications. Chitin and its derivative chitin oligosaccharides (CHOS) have potential biomedical and agricultural applications. Availability of CHOS with the desired length has been a major limitation in the optimum use of such natura...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Mohan Krishna Mallakuntla, Papa Rao Vaikuntapu, Bhoopal Bhuvanachandra, Subha Narayan Das, Appa Rao Podile
Formato: article
Lenguaje:EN
Publicado: Nature Portfolio 2017
Materias:
R
Q
Acceso en línea:https://doaj.org/article/d978bfdb29324565a6edf7e33c313060
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
Descripción
Sumario:Abstract Humans have exploited natural resources for a variety of applications. Chitin and its derivative chitin oligosaccharides (CHOS) have potential biomedical and agricultural applications. Availability of CHOS with the desired length has been a major limitation in the optimum use of such natural resources. Here, we report a single domain hyper-transglycosylating chitinase, which generates longer CHOS, from Enterobacter cloacae subsp. cloacae 13047 (EcChi1). EcChi1 was optimally active at pH 5.0 and 40 °C with a Km of 15.2 mg ml−1, and k cat/Km of 0.011× 102 mg−1 ml min−1 on colloidal chitin. The profile of the hydrolytic products, major product being chitobiose, released from CHOS indicated that EcChi1 was an endo-acting enzyme. Transglycosylation (TG) by EcChi1 on trimeric to hexameric CHOS resulted in the formation of longer CHOS for a prolonged duration. EcChi1 showed both chitobiase and TG activities, in addition to hydrolytic activity. The TG by EcChi1 was dependent, to some extent, on the length of the CHOS substrate and concentration of the enzyme. Homology modeling and docking with CHOS suggested that EcChi1 has a deep substrate-binding groove lined with aromatic amino acids, which is a characteristic feature of a processive enzyme.