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Direct electron transfer type disposable sensor strip for glucose sensing employing an engineered FAD glucose dehydrogenase

Paper ID Volume ID Publish Year Pages File Format Full-Text
17085 42639 2013 6 PDF Available
Title
Direct electron transfer type disposable sensor strip for glucose sensing employing an engineered FAD glucose dehydrogenase
Abstract

The FAD-dependent glucose dehydrogenase (FADGDH) from Burkholderia cepacia has several attractive features for glucose sensing. However, expanding the application of this enzyme requires improvement of its substrate specificity, especially decreasing its high activity toward maltose. A three-dimensional structural model of the FADGDH catalytic subunit was generated by homology modeling. By comparing the predicted active site with that of glucose oxidase, the two amino acid residues serine 326 and serine 365 were targeted for site-directed mutagenesis. The single mutations that produced the highest glucose specificity were combined, leading to the creation of the S326Q/S365Y double mutant, which was virtually nonreactive to maltose while retaining high glucose dehydrogenase activity. The engineered FADGDH was used to develop a direct electron transfer-type, disposable glucose sensor strip by immobilizing the enzyme complex onto a carbon screen-printed electrode. While the electrode employing wild-type FADGDH provided dangerously flawed results in the presence of maltose, the sensor employing our engineered FADGDH showed a clear glucose concentration-dependent response that was not affected by the presence of maltose.

► FADGDH is great for glucose sensing, but suffers from broad substrate specificity. ► 3D model of FADGDH was generated by homology modeling. ► Engineered FADGDH has no activity with maltose, retains high activity with glucose. ► Developed first direct electron transfer-type, disposable glucose sensor strip.

Keywords
Diabetes; Glucose dehydrogenase; Glucose sensor; SMBG; Substrate specificity; Direct electron transfer
First Page Preview
Direct electron transfer type disposable sensor strip for glucose sensing employing an engineered FAD glucose dehydrogenase
Publisher
Database: Elsevier - ScienceDirect
Journal: Enzyme and Microbial Technology - Volume 52, Issue 2, 5 February 2013, Pages 123–128
Authors
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Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering