Transglycosylating and hydrolytic activities of the beta-mannosidase from Trichoderma reesei.
Biochimie
; 91(5): 632-8, 2009 May.
Article
em En
| MEDLINE
| ID: mdl-19327384
ABSTRACT
A purified beta-mannosidase (EC 3.2.1.25) from the fungus Trichoderma reesei has been identified as a member of glycoside hydrolase family 2 through mass spectrometry analysis of tryptic peptides. In addition to hydrolysis, the enzyme catalyzes substrate transglycosylation with p-nitrophenyl beta-mannopyranoside. Structures of the major and minor products of this reaction were identified by NMR analysis as p-nitrophenyl mannobiosides and p-nitrophenyl mannotriosides containing beta-(1-->4) and beta-(1-->3) linkages. The rate of donor substrate hydrolysis increased in presence of acetonitrile and dimethylformamide, while transglycosylation was weakly suppressed by these organic solvents. Differential ultraviolet spectra of the protein indicate that a rearrangement of the hydrophobic environment of the active site following the addition of the organic solvents may be responsible for this hydrolytic activation.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Trichoderma
/
Proteínas Fúngicas
/
Beta-Manosidase
Idioma:
En
Ano de publicação:
2009
Tipo de documento:
Article