A highly thermoactive and salt-tolerant α-amylase isolated from a pilot-plant biogas reactor.
Appl Microbiol Biotechnol
; 97(7): 2971-8, 2013 Apr.
Article
em En
| MEDLINE
| ID: mdl-22743714
ABSTRACT
Aiming at the isolation of novel enzymes from previously uncultured thermophilic microorganisms, a metagenome library was constructed from DNA isolated from a pilot-plant biogas reactor operating at 55 °C. The library was screened for starch-degrading enzymes, and one active clone was found. An open reading frame of 1,461 bp encoding an α-amylase from an uncultured organism was identified. The amy13A gene was cloned in Escherichia coli, resulting in high-level expression of the recombinant amylase. The novel enzyme Amy13A showed the highest sequence identity (75%) to α-amylases from Petrotoga mobilis and Halothermothrix orenii. Amy13A is highly thermoactive, exhibiting optimal activity at 80 °C, and it is also highly salt-tolerant, being active in 25% (w/v) NaCl. Amy13A is one of the few enzymes that tolerate high concentrations of salt and elevated temperatures, making it a potential candidate for starch processing under extreme conditions.
Texto completo:
1
Coleções:
01-internacional
Contexto em Saúde:
3_ND
Base de dados:
MEDLINE
Assunto principal:
Reatores Biológicos
/
Alfa-Amilases
/
Metagenoma
Idioma:
En
Revista:
Appl Microbiol Biotechnol
Ano de publicação:
2013
Tipo de documento:
Article