Purification and characterization of a novel thermophilic ß-galactosidase from Picrophilus torridus of potential industrial application.
Extremophiles
; 23(6): 783-792, 2019 Nov.
Article
em En
| MEDLINE
| ID: mdl-31549249
ABSTRACT
Intracellular ß-galactosidase (E.C 3.2.1.23) produced by the thermoacidophilic archeon Picrophilus torridus DSM 9790 was purified to homogeneity using a combination of DEAE Sepharose, gel filtration, hydroxyapatite and chromatofocusing chromatographies. LC-MS/MS analysis was used to confirm the identity of the purified protein. The enzyme was found to be a homotrimer, with a molecular mass of 157.0 kDa and an isoelectric point of 5.7. To our knowledge, this enzyme has the lowest pH optimum of any intracellular ß-galactosidase characterized to date. Maximal activity was exhibited at acidic pH values of 5.0-5.5 and at 70 °C. The enzyme retained > 95% activity after heating to 70 °C for 1 h, or after incubation at pH 5.5 for 1 h. The enzyme may be of interest for high-temperature bioprocessing, such as in the production of lactulose. This investigation suggests that the ß-galactosidase activity produced by P. torridus is potentially more useful than several enzymes already characterized for such an application.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Beta-Galactosidase
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Thermoplasmales
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Proteínas Arqueais
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Temperatura Alta
Idioma:
En
Revista:
Extremophiles
Assunto da revista:
BIOLOGIA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Irlanda
País de publicação:
ALEMANHA
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ALEMANIA
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DE
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DEUSTCHLAND
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GERMANY