Cytochromes as electron shuttles from FAD-dependent glucose dehydrogenase to electrodes

Schachinger, Franziska; Scheiblbrandner, Stefan; Karnpakdee, Kwankao; Breslmayr, Erik; Ma, Su; Ludwig, Roland

doi:10.1016/j.electacta.2023.142485

Cited by 4 publications

(2 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To optimize DET in this field focuses not only on the development of electrode materials, nanostructures, and protein immobilization strategies but also on protein engineering strategies. One approach involves fusing a CYT domain onto a single-domain enzyme to mimic the function of CDH. , Establishing a CYT library expands the potential for utilizing CYT as an electron shuttle for a wider range of biocatalysts. , In this and other enzyme engineering approaches, maintaining or improving DET while optimizing the interdomain electron transfer (IET) is crucial. , The basis for these strategies lies in the structures of two ascomycete CDHs from Crassicarpon hotsonii (syn. Myriococcum thermophilum, 4QI6) and Neurospora crassa (4QI7), which feature a closed-state and an open-state conformation of the domains, respectively .…”

Section: Introductionmentioning

confidence: 99%

“… 13 , 14 Establishing a CYT library expands the potential for utilizing CYT as an electron shuttle for a wider range of biocatalysts. 15 , 16 In this and other enzyme engineering approaches, maintaining or improving DET while optimizing the interdomain electron transfer (IET) is crucial. 17 , 18 The basis for these strategies lies in the structures of two ascomycete CDHs from Crassicarpon hotsonii (syn.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Interdomain Linker of the Bioelecrocatalyst Cellobiose Dehydrogenase Governs the Electron Transfer

et al. 2023

Self Cite

View full text Add to dashboard Cite

Direct bioelectrocatalysis applied in biosensors, biofuel cells, and bioelectrosynthesis is based on an efficient electron transfer between enzymes and electrodes in the absence of redox mediators. Some oxidoreductases are capable of direct electron transfer (DET), while others achieve the enzyme to electrode electron transfer (ET) by employing an electron-transferring domain. Cellobiose dehydrogenase (CDH) is the most-studied multidomain bioelectrocatalyst and features a catalytic flavodehydrogenase domain and a mobile, electron-transferring cytochrome domain connected by a flexible linker. The ET to the physiological redox partner lytic polysaccharide monooxygenase or, ex vivo, electrodes depends on the flexibility of the electron transferring domain and its connecting linker, but the regulatory mechanism is little understood. Studying the linker sequences of currently characterized CDH classes we observed that the inner, mobile linker sequence is flanked by two outer linker regions that are in close contact with the adjacent domain. A function-based definition of the linker region in CDH is proposed and has been verified by rationally designed variants of Neurospora crassa CDH. The effect of linker length and its domain attachment on electron transfer rates has been determined by biochemical and electrochemical methods, while distances between the domains of CDH variants were computed. This study elucidates the regulatory mechanism of the interdomain linker on electron transfer by determining the minimum linker length, observing the effects of elongated linkers, and testing the covalent stabilization of a linker part to the flavodehydrogenase domain. The evolutionary guided, rational design of the interdomain linker provides a strategy to optimize electron transfer rates in multidomain enzymes and maximize their bioelectrocatalytic performance.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Interdomain Linker of the Bioelecrocatalyst Cellobiose Dehydrogenase Governs the Electron Transfer

et al. 2023

Self Cite

View full text Add to dashboard Cite

show abstract

Electron Transfer of Cellobiose Dehydrogenase in Polyethyleneimine Films

Karnpakdee,

Kracher,

Ludwig

2024

ChemElectroChem

Self Cite

View full text Add to dashboard Cite

Cellobiose dehydrogenase (CDH) is applied as a bioelectrocatalyst in biosensors because its mobile cytochrome domain is capable of direct electron transfer. This study investigates the electron transfer mechanism of CDH molecules embedded in the polycation polyethyleneimine (PEI), which has been reported as a current‐boosting component of CDH‐based biosensors. By immobilizing different concentrations of CDH and its isolated cytochrome domain in PEI films, we found that increasing concentrations of cytochrome enhanced the film conductivity (up to 251±8 mS cm−1) through improved electron transfer between the protein redox centers. The increased electrical conductivity of the film contacts CDH molecules at a greater distance from the electrode. The cross‐linker poly(ethylene glycol) diglycidyl ether improves the packing and contacting of the cytochrome domains, whereas glutaraldehyde reduces the current obtained. Deglycosylation of CDH enhances the conductivity of enzyme‐polymer films by up to 34 %, implying a higher number of productive electron‐hopping events between cytochrome domains due to enhanced mobility or reduced shielding. By balancing negative charges on the CDH surface at neutral and alkaline pH, PEI increases the interdomain electron transfer and the electrical film conductivity. The resulting increased current output is relevant for in vivo bioanalytical applications.

show abstract

Advanced strategies for enzyme–electrode interfacing in bioelectrocatalytic systems

Lee,

Reginald,

Sravan

et al. 2024

Trends in Biotechnology

View full text Add to dashboard Cite

Cytochromes as electron shuttles from FAD-dependent glucose dehydrogenase to electrodes

Cited by 4 publications

References 56 publications

Interdomain Linker of the Bioelecrocatalyst Cellobiose Dehydrogenase Governs the Electron Transfer

Interdomain Linker of the Bioelecrocatalyst Cellobiose Dehydrogenase Governs the Electron Transfer

Electron Transfer of Cellobiose Dehydrogenase in Polyethyleneimine Films

Advanced strategies for enzyme–electrode interfacing in bioelectrocatalytic systems

Contact Info

Product

Resources

About