Abstract
We present a methodology for improving some enzymatic characteristics of glucose oxidase (GOx) (EC 1.1.3.4). The enzyme was chemically modified with a β-cyclodextrin-branched carboxymethylcellulose polymer (CMC-CD), using carbodiimide as coupling agent. The obtained neoglycoenzyme had 0.78 mol of polysaccharide per mol of GOx and retained 67% of its initial activity. Comparison of some characteristics of the modified and free enzymes showed a higher Km for derivatized GOx and better thermostability, which increased from 45 ° C to 51 ° C. In addition, derivatization of GOx with CMC-CD increased its resistance to inactivation at 45 ° C by 2.2-fold, protected the molecule against inactivation with the anionic surfactant sodium dodecylsulphate to the point that it retained 75% of its activity after an incubation of 3 h, and extended its pH tolerance toward alkaline pH (7.5). Covalent glycosidation of glucose oxidase with CD-branched carboxymethylcellulose polymer constitutes therefore an effective strategy for enhancing the stability of this enzyme.
Original language | English |
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Pages (from-to) | 29-34 |
Number of pages | 6 |
Journal | Biotecnologia Aplicada |
Volume | 29 |
Issue number | 1 |
Publication status | Published - Jan 2012 |
Externally published | Yes |
Keywords
- Carboxymethylcellulose
- Cyclodextrin
- Enzyme stability
- Glucose oxidase