Isolation and characterisation of a novel alpha-amylase from the extreme haloarchaeon Haloterrigena turkmenica.
Int J Biol Macromol
; 92: 174-184, 2016 Nov.
Article
em En
| MEDLINE
| ID: mdl-27377461
ABSTRACT
An extracellular halophilic alpha-amylase (AmyA) was produced by the haloarchaeon Haloterrigena turkmenica grown in medium enriched with 0.2% (w/v) starch. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and size exclusion chromatography (SEC) analyses showed a major band at 66.0kDa and a peak of 54.0kDa, respectively. Analysis of tryptic fragments of the protein present in the major SDS-PAGE band by nano-LC-ESI-MS/MS led to identification of the alpha-amylase catalytic region, encoded by the htur2110 gene, as the protein possessing the described activity. Optimal values for activity were 55°C, pH 8.5 and 2M NaCl, and high thermostability was showed at 55°C and 3M NaCl. AmyA activity was enhanced by Triton X-100 and was not influenced by n-hexane and chloroform. Starch hydrolysis produced different oligomers with maltose as the smallest end-product. The efficiency of AmyA in degrading starch contained in agronomic residues was tested in grape cane chosen as model substrate. Preliminary results showed that starch was degraded making the enzyme a potential candidate for utilization of agro-industrial waste in fuel and chemicals production. AmyA is one of the few investigated amylases produced by haloarchaea, and the first alpha-amylase described among microorganisms belonging to the genus Haloterrigena.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Archaea
/
Alfa-Amilases
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Int J Biol Macromol
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
Itália