| Title |
Effect of Glycosylation on the Biochemical Properties of beta-Xylosidases from Aspergillus versicolor |
| Author |
Alexandre Favarin Somera1, Marita Gimenez Pereira1, Luis Henrique Souza Guimaraes1, Maria de Lourdes Teixeira de Moraes Polizeli1, Hector Francisco Terenzi1, Rosa Prazeres Melo Furriel2, and Joao Atilio Jorge1* |
| Address |
1Departamentos de Biologia e Quimica, Universidade de Sao Paulo, Avenida Bandeirantes, 3900, CEP 14040-901 Ribeirao Preto, SP, Brasil, 2Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Avenida Bandeirantes, 3900, CEP 14040-901 Ribeirau Preto, SP, Brasil |
| Bibliography |
Journal of Microbiology, 47(3),270-276, 2009,
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| DOI |
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| Key Words |
beta-xylosidase, xylobiase, glycosylation, deglycosylation, glycoprotein, Aspergillus versicolor |
| Abstract |
Aspergillus versicolor grown on xylan or xylose produces two beta-xylosidases with differences in biochemical properties and degree of glycosylation. We investigated the alterations in the biochemical properties of these beta-xylosidases after deglycosylation with Endo-H or PNGase F. After deglycosylation, both enzymes migrated faster in PAGE or SDS-PAGE exhibiting the same Rf. Temperature optimum of xylan-induced and xylose-induced beta-xylosidases was 45oC and 40oC, respectively, and 35oC after deglycosylation. The xylan- induced enzyme was more active at acidic pH. After deglycosylation, both enzymes had the same pH optimum of 6.0. Thermal resistance at 55oC showed half-life of 15 min and 9 min for xylose- and xylan-induced enzymes, respectively. After deglycosylation, both enzymes exhibited half-lives of 7.5 min. Native enzymes exhibited different responses to ions, while deglycosylated enzymes exhibited identical responses. Limited proteolysis yielded similar polypeptide profiles for the deglycosylated enzymes, suggesting a common polypeptide core with differential glycosylation apparently responsible for their biochemical and biophysical differences. |
