Protopectinase-se from <i>Geotrichum klebahnii</i>: Studies of the adsorption and pectin-solubilization capacity

Protopectinase SE (PPase-SE) is a polygalacturonase produced by Geotrichum klebahnii with the capacity to liberate pectin through protopectin hydrolysis. The protopectin cleavage is a typical heterogeneous-catalysis reaction whose interaction between the enzyme and the protopectin substrate from lem...

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Detalles Bibliográficos
Autores: Zapata Zapata, Arley David, Hours, Roque Alberto, Cavalitto, Sebastián Fernando
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2017
País:Argentina
Institución:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/77307
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/77307
Access Level:acceso abierto
Palabra clave:Química
Pectinas
protopectin
protopectinase-SE
Langmuir isotherm
Michaelis-Menten
Descripción
Sumario:Protopectinase SE (PPase-SE) is a polygalacturonase produced by Geotrichum klebahnii with the capacity to liberate pectin through protopectin hydrolysis. The protopectin cleavage is a typical heterogeneous-catalysis reaction whose interaction between the enzyme and the protopectin substrate from lemon albedo along with the release of the pectin-reaction product were the objectives of this investigation. The interaction between PPase-SE and protopectin depended on the particle size and the structure of the substrate as well as on the nature of the buffer. The adsorption kinetics follows, for small particles, a Langmuir isotherm pattern. The reaction exhibited Michaelis-Menten kinetics, giving respective apparent-Km and Vmax values of 30.2 g/l and 57.3 g/l.h. The better results in enzyme adsorption and pectin releasing were obtained with citrate and citrate-phosphate buffers. This report constitutes the first investigation in pectin solubilization involving a model for the substrate-binding mechanism within the pectinase-protopectinase system.