Bioproduction of D-Tagatose from D-Galactose Using Phosphoglucose Isomerase from Pseudomonas aeruginosa PAO1.
Appl Biochem Biotechnol
; 179(5): 715-27, 2016 Jul.
Article
em En
| MEDLINE
| ID: mdl-26922727
Pseudomonas aeruginosa PAO1 phosphoglucose isomerase was purified as an active soluble form by a single-step purification using Ni-NTA chromatography that showed homogeneity on SDS-PAGE with molecular mass â¼62 kDa. The optimum temperature and pH for the maximum isomerization activity with D-galactose were 60 °C and 7.0, respectively. Generally, sugar phosphate isomerases show metal-independent activity but PA-PGI exhibited metal-dependent isomerization activity with aldosugars and optimally catalyzed the D-galactose isomerization in the presence of 1.0 mM MnCl2. The apparent Km and Vmax for D-galactose under standardized conditions were calculated to be 1029 mM (±31.30 with S.E.) and 5.95 U/mg (±0.9 with S.E.), respectively. Equilibrium reached after 180 min with production of 567.51 µM D-tagatose from 1000 mM of D-galactose. Though, the bioconversion ratio is low but it can be increased by immobilization and enzyme engineering. Although various L-arabinose isomerases have been characterized for bioproduction of D-tagatose, P. aeruginosa glucose phosphate isomerase is distinguished from the other L-arabinose isomerases by its optimal temperature (60 °C) for D-tagatose production being mesophilic bacteria, making it an alternate choice for bulk production.
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MEDLINE
Assunto principal:
Pseudomonas aeruginosa
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Glucose-6-Fosfato Isomerase
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Hexoses
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article