Purification and partial characterization of an acidic polygalacturonase from Aspergillus kawachii

An endo-polygalacturonase, named PGI, was purified to homogeneity from the culture filtrate of Aspergillus kawachii IFO 4033 grown in a glucose-tryptone medium. The molecular mass of PGI was estimated to be 60kDa by SDS-PAGE and 40kDa by gel filtration on Sephacryl S-100. The isoelectric point was 3...

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Detalles Bibliográficos
Autores: Contreras Esquivel, J.C., Voget, Claudio Enrique
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2004
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/100677
Acceso en línea:http://hdl.handle.net/11336/100677
Access Level:acceso abierto
Palabra clave:ACIDIC ENZYMES
ASPERGILLUS KAWACHII
ENDO-POLYGALACTURONASE
PECTIN
https://purl.org/becyt/ford/2.9
https://purl.org/becyt/ford/2
Descripción
Sumario:An endo-polygalacturonase, named PGI, was purified to homogeneity from the culture filtrate of Aspergillus kawachii IFO 4033 grown in a glucose-tryptone medium. The molecular mass of PGI was estimated to be 60kDa by SDS-PAGE and 40kDa by gel filtration on Sephacryl S-100. The isoelectric point was 3.55 as determined by isoelectic focusing. PGI exhibited binding properties to ConA-Sepharose suggesting that the protein is glycosylated. The N-terminal amino acid sequence was also determined as S-T-C-T-F-T-D-A-A-T-A-S-E-S-K. The remarkable property of PGI was its high activity in the pH range 2.0-3.0 towards soluble and insoluble substrates, while being inactive at pH 5.0. Enzyme stability at low pHs was markedly enhanced by different compounds, such as proteins, polysaccharides, simple sugars and the substrate pectin. PGI was very efficient to extract pectin from lemmon protopectin and to macerate carrot tissues at pH 2.0. These properties make PGI an interesting biocatalyst for industrial applications under highly acidic conditions.