Thermophilic Talaromyces emersonii Flavin Adenine Dinucleotide-Dependent Glucose Dehydrogenase Bioanode for Biosensor and Biofuel Cell Applications

Abstract

Flavin adenine dinucleotide (FAD)-dependent glucose dehydrogenase (GDH) was identified and cloned from thermophilic filamentous fungi Talaromyces emersonii using the homology cloning method. A direct electron transfer bioanode composed of T. emersonii FAD-GDH and a single-walled carbon nanotube was produced. Enzymes from thermophilic microorganisms generally have low activity at ambient temperature; however, the T. emersonii FAD-GDH bioanode exhibits a large anodic current due to the enzymatic reaction (1 mA cm–2) at ambient temperature. Furthermore, the T. emersonii FAD-GDH bioanode worked at 70 °C for 12 h. This is the first report of a bioanode with a glucose-catalyzing enzyme from a thermophilic microorganism that has potential for biosensor and biofuel cell applications. In addition, we demonstrate how the glycoforms of T. emersonii FAD-GDHs expressed by various hosts influence the electrochemical properties of the bioanode.

Comparison of Direct and Mediated Electron Transfer in Electrodes with Novel Fungal Flavin Adenine Dinucleotide Glucose Dehydrogenase

“…Glycosylation by fungus stabilized FAD-GDH against heat and pH was demonstrated previously. 2,34,35 Therefore, in addition to being able to be produced efficiently, our novel glycosylated FAD-GDH is stable in harsh conditions.…”

“…Oxygen-insensitive flavin adenine dinucleotide-dependent glucose dehydrogenase (FAD-GDH) has been given much attention recently and there has been an increasing numbers of related reports on biosensors [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] and biofuel cells. 13,14,[16][17][18] Recently, the structure of FAD-GDH from Aspergillus flavus was unveiled and it was found that an FAD cofactor is buried deeply (∼1.4 nm) below the protein surface.…”

Effect of Electrolyte Ions on the Stability of Flavin Adenine Dinucleotide‐Dependent Glucose Dehydrogenase

“…Although FAD‐GDH has already been used in single‐use blood glucose sensor strips, the long‐term usage of FAD‐GDH‐based electrodes operating at body temperature is limited by the inactivation of enzymes on electrodes because FAD‐GDH has a lower thermal stability than GOx . To extend the lifetime of the enzyme, promising straightforward strategies include the screening of more thermostable FAD‐GDHs from other sources or developing protein‐engineered FAD‐GDHs . Alternatively, the use of additives for enzyme stabilization can also be considered as a practical and immediate method, in particular for BFC application .…”

Tackling the Challenges of Enzymatic (Bio)Fuel Cells

“…283,[524][525][526][527][528][529][530][531][532][533] . Milton et al found that a GOx based membrane-less EFC initially had a higher power density than a FAD-GDH based EFC, while the FAD-GDH based EFC possessed better operating stability (after 24 h continuous operation)525 .This confirms the negative effects of GOx bioanodes producing H 2 O 2 on BOD525 and Lac530 biocathodes.…”