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Peptide sequence-driven direct electron transfer properties and binding behaviors of gold-binding peptide-fused glucose dehydrogenase on electrode

ABSTRACT: Summary Oriented enzyme immobilization on electrodes is crucial for interfacial electrical coupling of direct electron transfer (DET)-based enzyme-electrode systems. As inorganic-binding peptides are introduced as molecular binders and enzyme-orienting agents, inorganic-binding peptide-fused enzymes should be designed and constructed to achieve efficient DET. In this study, it is aimed to compare the effects of various gold-binding peptides (GBPs) fused to enzymes on electrocatalytic activity, bioactivity, and material-binding behaviors. Here, GBPs with identical gold-binding properties but different amino acid sequences were fused to the FAD-dependent glucose dehydrogenase gamma-alpha complex (GDHγα) to generate four GDHγα variants. The structural, biochemical, mechanical, and bioelectrochemical properties of these GDHγα variants immobilized on electrode were determined by their fused GBPs. Our results confirmed that the GBP type is vital in the design, construction, and optimization of GBP-fused enzyme-modified electrodes for facile interfacial DET and practical DET-based enzyme-electrode systems. Graphical abstract Highlights • The four GBP sequences are genetically fused to catalytic subunit of GDHγα complex• The cofactor-surface interface was investigated with 3D models of fusion enzymes• The four systems exhibit diverse electrochemical results depending on GBP type Electrochemistry; Bio-electrochemistry; Materials science; Materials chemistry

SUBMITTER: Lee H

PROVIDER: S-EPMC8593565 | biostudies-literature |

REPOSITORIES: biostudies-literature

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