Direct electron transfer of bilirubin oxidase (Myrothecium verrucaria) at an unmodified nanoporous gold biocathode

Salaj-Kośla, Urszula; Pöller, Sascha; Beyl, Yvonne; Scanlon, Micheál D.; Beloshapkin, Sergey; Shleev, Sergey; Schuhmann, Wolfgang; Magner, Edmond

doi:10.1016/j.elecom.2011.12.007

Cited by 81 publications

(52 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As reported previously, the linkages formed by chemisorption of the NH 2 groups of the lysine residues of ThLc on nanoporous gold are as strong as those for -SH groups on gold [32]. However, a P017-epoxy cap was also applied [33] to prevent any possible leaching of the enzyme from the gold surface. The P017-epoxy stabilises the adsorbed enzyme by creating covalent bonds with amine, thiol, or hydroxyl nucleophilic groups on the surface of the enzyme and enables the enzyme to be retained in the pores [34].…”

Section: Resultsmentioning

confidence: 91%

See 1 more Smart Citation

Direct electron transfer of Trametes hirsuta laccase adsorbed at unmodified nanoporous gold electrodes

Salaj-Kośla

Pöller

Schuhmann

et al. 2013

Bioelectrochemistry

Self Cite

View full text Add to dashboard Cite

The enzyme Trametes hirsuta laccase undergoes direct electron transfer at unmodified nanoporous gold electrodes, displaying a current density of 28 A/cm 2 . The response indicates that ThLc was immobilised at the surface of the nanopores in a manner which promoted direct electron transfer, in contrast to the absence of a response at unmodified polycrystalline gold electrodes. The bioelectrocatalytic activity of ThLc modified nanoporous gold electrodes was strongly dependent on the presence of halide ions. Fluoride completely inhibited the enzymatic response, whereas in the presence of 150 mM Cl -, the current was reduced to 50% of the response in the absence of Cl -. The current increased by 40% when the temperature was increased from 20°C to 37°C. The response is limited by enzymatic and/or enzyme electrode kinetics and is 30% of that observed for ThLc co-immobilised with an osmium redox polymer. Keywords: Laccase, direct electron transfer, nanoporous gold 2 IntroductionElectron transfer (ET) reactions are ubiquitous in nature. Controlling the rate of these reactions can be of significant benefit in developing biochemical systems that utilise redox proteins and enzymes and in particular, in applications that provide power for implanted or portable electronic devices. ET can be achieved directly (direct electron transfer, DET) or by the use of mediators (mediated electron transfer, MET) to shuttle electrons between the redox centre of the enzyme and the electrode. However, mediators are unselective and can also give rise to interfering effects [1][2][3]. DET-based devices offer high selectivity and sensitivity due to the absence of mediators. In addition, devices based on DET operate at potentials close to the redox potential of the enzyme, maximising the potential difference between the cathode and anode for biofuel cell applications [2]. Moreover, DET can be used to provide detailed information on the kinetics and thermodynamics of the ET process. However, the low stability of the enzyme layer together with the long distances over which ET occurs, represent major obstacles for DET based devices. In addition, the shielding mechanism of the enzymatic redox centre by the protein shell can disrupt DET [2,4]. One approach in optimizing and enabling rapid DET is to design the electrode surface with an architecture which promotes efficient rates of ET. In this way the electrode morphology ensures the most efficient orientation of the enzymatic redox centre and facilitates communication with the electroactive surface. Porous electrodes can be used to encapsulate the enzyme within a network of cavities, shortening the distance for electron transfer to the redox active site, which will promote more efficient and rapid rates of electron transfer [5]. However, the number of redox enzymes capable of interacting directly with the electrode while catalyzing the enzymatic reaction is limited, with estimates of approximately 5% of all enzymes exhibiting such a response [6].DET in enzymes was first described in 1978 fo...

show abstract

Section: Resultsmentioning

confidence: 91%

“…Using a similar immobilisation method for the adsorption of BOx resulted in an O 2 -sensitive BOx biocathode with a biocatalytic current density of ca. 200 µA (on a 0.246 cm 2 electrode) [33]. The response of this electrode was limited by diffusion of O 2 .…”

Section: Resultsmentioning

confidence: 99%

Direct electron transfer of Trametes hirsuta laccase adsorbed at unmodified nanoporous gold electrodes

Salaj-Kośla

Pöller

Schuhmann

et al. 2013

Bioelectrochemistry

Self Cite

View full text Add to dashboard Cite

show abstract

“…BOD was physically embedded into bare NPG and the resulted electrodes displayed bioelectrocatalytic reduction of molecular oxygen, undergoing efficient DET (Figure 8) [76]. However, BOD was 35 relatively loosely bound and easily removed from the surface of the electrode as only 50% of potential scan was retained in second scan.…”

Section: Multi-copper Oxidasesmentioning

confidence: 99%

An overview of dealloyed nanoporous gold in bioelectrochemistry

Xiao

Magner

2016

Bioelectrochemistry

Self Cite

109

View full text Add to dashboard Cite

show abstract

“…[30,[32][33][34][35] Physiologically, electrons are received from the substrate to the T1 Cu and transfer through a histidine-cysteine bridge to the trinuclear cluster 12-14 away, where O 2 reduction takes place (Figure 2 B). Some intermediates in the catalytic mechanism, in particular in the presence of inhibitors or under conditions of low or high potentials, are still under consideration.…”

Section: Enzymes For O 2 Reductionmentioning

confidence: 99%

Biohydrogen for a New Generation of H₂/O₂ Biofuel Cells: A Sustainable Energy Perspective

et al. 2014

View full text Add to dashboard Cite

Among sustainable alternatives to fossil fuel, proton exchange membrane fuel cells are promising devices that deliver electricity from hydrogen and oxygen, producing only water. The transformation of the fuel and oxidant however relies on rare‐metal catalysts. H2/O2 enzymatic biofuel cells thus emerge as sustainable biotechnological devices in which chemical catalysts are replaced by hydrogenases at the anode and multicopper oxidases at the cathode. This review discusses the recent breakthroughs and the limitations in all the components of H2/O2 biofuel cells: 1) Catalytic mechanisms involved in multicopper oxidases and hydrogenases, in addition to the new potential of enzymes from the biodiversity pool, which exhibit outstanding properties. 2) The molecular basis for oriented enzyme immobilization on the electrochemical interfaces as a prerequisite for a fast direct electron‐transfer rate. 3) The requirement for 3D networks to enhance current densities. 4) The production of H2 from biomass. 5) The history of H2/O2 biofuel cells and recent devices, which also highlights the remaining issues that will allow the use of such devices in low‐power applications.

show abstract

Direct electron transfer of bilirubin oxidase (Myrothecium verrucaria) at an unmodified nanoporous gold biocathode

Cited by 81 publications

References 21 publications

Direct electron transfer of Trametes hirsuta laccase adsorbed at unmodified nanoporous gold electrodes

Direct electron transfer of Trametes hirsuta laccase adsorbed at unmodified nanoporous gold electrodes

An overview of dealloyed nanoporous gold in bioelectrochemistry

Biohydrogen for a New Generation of H₂/O₂ Biofuel Cells: A Sustainable Energy Perspective

Contact Info

Product

Resources

About

Direct electron transfer of bilirubin oxidase (Myrothecium verrucaria) at an unmodified nanoporous gold biocathode

Cited by 81 publications

References 21 publications

Direct electron transfer of Trametes hirsuta laccase adsorbed at unmodified nanoporous gold electrodes

Direct electron transfer of Trametes hirsuta laccase adsorbed at unmodified nanoporous gold electrodes

An overview of dealloyed nanoporous gold in bioelectrochemistry

Biohydrogen for a New Generation of H2/O2 Biofuel Cells: A Sustainable Energy Perspective

Contact Info

Product

Resources

About

Biohydrogen for a New Generation of H₂/O₂ Biofuel Cells: A Sustainable Energy Perspective