Characterization of a recombinant mannobiose 2-epimerase from Spirochaeta thermophila that is suggested to be a cellobiose 2-epimerase.
Biotechnol Lett
; 35(11): 1873-80, 2013 Nov.
Article
em En
| MEDLINE
| ID: mdl-23801120
ABSTRACT
A purified recombinant enzyme from Spirochaeta thermophila, that is suggested to be a cellobiose 2-epimerase, was a 47 kDa monomer with a specific activity of 29.2 U min(-1) for mannobiose. The epimerization activity of the recombinant enzyme for mannobiose was maximal at pH 7.0 and 60 °C with a half-life of 124 h. The enzyme exhibited a higher epimerization activity for mannose or the mannose moiety at the reducing end of ß- and α-1,4-glycosyl-mannose than for glucose or the glucose moiety of ß- and α-1,4-glycosyl-glucose. The enzyme was identified as a mannobiose 2-epimerase by evaluating its substrate specificity with not only glucose-containing sugars but also mannose-containing sugars. The activities of the reported cellobiose 2-epimerases from Caldicellulosiruptor saccharolyticus, Dictyoglomus turgidum and Ruminococcus marinus for mannobiose were higher than those for cellobiose, strongly suggesting that these enzymes are not cellobiose 2-epimerases but are mannobiose 2-epimerases.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Spirochaeta
/
Carboidratos Epimerases
/
Mananas
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article