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Ahmed,Samia A.; El-Shayeb,Nefisa M.A.; Hashem,Abdel-Gawad M.; Saleh,Shireen A.A.; Abdel-Fattah,Ahmed F.. |
Aspergillus niger β-glucosidase was modified by covalent coupling to periodate activated polysaccharides (glycosylation). The conjugated enzyme to activated starch showed the highest specific activity (128.5 U/mg protein). Compared to the native enzyme, the conjugated form exhibited: a higher optimal reaction temperature, a lower Ea (activation energy), a higher Km (Michaelis constant) and Vmax (maximal reaction rate), and improved thermal stability. The calculated t1/2 (half-life) values of heat in-activation at 60 °C and 70 °C were 245.7 and 54.5 min respectively, whereas at these temperatures the native enzyme was less stable (t1/2of 200.0 and 49.5 min respectively). The conjugated enzyme retained 32.3 and 29.7%, respectively from its initial activity... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Β-glucosidases; Glycosylation; Soluble polysaccharides; Enzyme stability. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822015000100023 |
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