Purification and characterization of a cold-adapted pullulanase from a psychrophilic bacterial isolate.
Extremophiles
; 18(6): 1095-102, 2014 Nov.
Article
em En
| MEDLINE
| ID: mdl-25069876
ABSTRACT
There is a considerable potential of cold-active biocatalysts for versatile industrial applications. A psychrophilic bacterial strain, Shewanella arctica 40-3, has been isolated from arctic sea ice and was shown to exhibit pullulan-degrading activity. Purification of a monomeric, 150-kDa pullulanase was achieved using a five-step purification approach. The native enzyme was purified 50.0-fold to a final specific activity of 3.0 U/mg. The enzyme was active at a broad range of temperature (10-50 °C) and pH (5-9). Optimal activity was determined at 45 °C and pH 7. The presence of various metal ions is tolerated by the pullulanase, while detergents resulted in decreased activity. Complete conversion of pullulan to maltotriose as the sole product and N-terminal amino acid sequence indicated that the enzyme is a type-I pullulanase and belongs to rarely characterized pullulan-degrading enzymes from psychrophiles.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
/
Temperatura Baixa
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Shewanella
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Glicosídeo Hidrolases
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article