Electrochemical redox transformations of T1 and T2 copper sites in native<i>Trametes hirsuta</i>laccase at gold electrode

Shleev, Sergey; Christenson, Andreas; Сереженков, В. А.; Burbaev, D. Sh.; Yaropolov, A. I.; Gorton, Lo; Ruzgas, Tautgirdas

doi:10.1042/bj20041015

Cited by 160 publications

(164 citation statements)

References 43 publications

Supporting

Mentioning

147

Contrasting

Order By: Relevance

“…Obviously, half-wave potentials registered in our studies ( Figure 3) coincide well with the redox potential of Trametes hirsuta Lc, measured to be 780 mV ± 10 mV versus NHE at pH about 6 [39,42]. We also noticed that the initial parts of both curves, 1 and 2, are almost identical, pointing to the fact that at low overpotentials, the bioelectrochemical reaction of O 2 reduction occurs in the kinetic mode, i.e.…”

Section: Time / Dayssupporting

confidence: 64%

Stable ‘Floating' Air Diffusion Biocathode Based on Direct Electron Transfer Reactions Between Carbon Particles and High Redox Potential Laccase

et al. 2010

View full text Add to dashboard Cite

We report on the assembly and characterisation of a high potential, stable, mediator‐less and cofactor free biocathode based on a fungal laccase (Lc), adsorbed on highly dispersed carbonaceous materials. First, the stability and activity of Trametes hirsuta Lc immobilised on different carbon particles were studied and compared to the solubilised enzyme. Based on the experimental results and a literature analysis, the carbonaceous material BM‐4 was chosen to design efficient and stable biocatalysts for the production of a ‘floating' air diffusion Lc‐based biocathode. Voltammetric characteristics and operational stability of the biocathode were investigated. The current density of oxygen reduction at the motionless biocathode in a quiet, air saturated citrate buffer (100 mM, pH 4.5, 23 °C) reached values as high as 0.3 mA cm–2 already at 0.7 V versus NHE. The operational stability of the biocathode depended on the current density of the device. For example, at low current density (20 μA cm–2), the biocathode lost only 5× of its initial power after 1 month of continuous operation. However, when the device was polarised at 150 mV it lost more than 32× of its initial power in just 10 min. We also found that co‐immobilisation of Lc and peroxidase on highly dispersed carbon materials could protect the biocatalyst from rapid inactivation by hydrogen peroxide produced during electrocatalytic reactions at high‐current densities.

show abstract

Section: Time / Dayssupporting

confidence: 64%

Stable ‘Floating' Air Diffusion Biocathode Based on Direct Electron Transfer Reactions Between Carbon Particles and High Redox Potential Laccase

et al. 2010

View full text Add to dashboard Cite

show abstract

“…[47,[61][62] At least one of these processes might be attributed to a trinuclear cluster intermediate. [41,47,[63][64] An uphill intramolecular electron transfer was thus proposed, which was confirmed both by electrochemistry and quantum and molecular mechanical calculations. [60] This process is, however, still a matter of debate because the catalytic cycle involves highly oxidative species.…”

Section: Enzymes For O 2 Reductionmentioning

confidence: 57%

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

“…The low redox potential Faradaic processes (at ca. 0.4 V vs. NHE) detected for surface confined Lc on gold has been attributed to the redox transformation of copper ion(s) from the T2/T3 Cu cluster [19][20][21][22][23]. An explanation of the absence of bioelectrocatalytic activity has been not clearly identified.…”

mentioning

confidence: 95%

“…An explanation of the absence of bioelectrocatalytic activity has been not clearly identified. Several hypotheses have been proposed including the formation of catalytically inactive but electrochemically active forms of Lc arising from specific enzyme orientation at the electrode surface [19]. Denaturation (protein unfolding) of the enzymes on bare Au surface can also account for the observed effects.…”

mentioning

confidence: 99%

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

Electrochemical redox transformations of T1 and T2 copper sites in nativeTrametes hirsutalaccase at gold electrode

Cited by 160 publications

References 43 publications

Stable ‘Floating' Air Diffusion Biocathode Based on Direct Electron Transfer Reactions Between Carbon Particles and High Redox Potential Laccase

Stable ‘Floating' Air Diffusion Biocathode Based on Direct Electron Transfer Reactions Between Carbon Particles and High Redox Potential Laccase

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

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

Contact Info

Product

Resources

About

Electrochemical redox transformations of T1 and T2 copper sites in nativeTrametes hirsutalaccase at gold electrode

Cited by 160 publications

References 43 publications

Stable ‘Floating' Air Diffusion Biocathode Based on Direct Electron Transfer Reactions Between Carbon Particles and High Redox Potential Laccase

Stable ‘Floating' Air Diffusion Biocathode Based on Direct Electron Transfer Reactions Between Carbon Particles and High Redox Potential Laccase

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

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

Contact Info

Product

Resources

About

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