Defect Levels in Nuclear Detector Grade Cd<sub>0.9</sub>Zn<sub>0.1</sub>Te Crystals

Construction of artificial allosteric protein switches is one of the central goals of synthetic biology that holds promise to transform the way we detect and quantify substances in vitro and in vivo. An artificial chimeric fusion protein of pyrroloquinoline quinone‐dependent glucose dehydrogenase with calmodulin (PQQ‐GDH‐CaM) was covalently attached to graphene nanosheets produced electrochemically on a carbon fiber electrode. The chimeric PQQ‐GDH‐CaM represents an artificial allosteric switch activated by association of a calmodulin‐binding peptide with the Ca2+‐bound calmodulin domain. The activity of the immobilized enzyme was switched between active and inactive states by adding/removing the activating peptide. The peptide‐signal switchable features originated from the enzyme 3D‐structural variations induced by the conformational (folding/unfolding) changes in the connected calmodulin unit upon formation/dissociation of its complex with the specific peptide. The peptide‐activated immobilized PQQ‐GDH‐CaM enzyme displayed direct (non‐mediated) electron transfer to the conducting electrode support upon glucose oxidation. On the contrary, in the absence of the peptide, the inactive form of the enzyme demonstrated very low bioelectrocatalytic activity for glucose oxidation. Since the conformational changes of the PQQ‐GDH‐CaM depend on the presence of Ca2+ cations and the calmodulin‐binding peptide, both of them were used as input signals to control the enzyme activity mimicking a Boolean AND logic gate. The switchable behavior of the enzyme‐modified electrode was studied electrochemically and used to assemble a signal‐switchable biofuel cell. The use of the peptide as the signaling messenger enables the design of generalizable bioelectronic systems controlled by native and synthetic biochemical signaling systems.

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Highly Porous Gold Electrodes – Preparation and Characterization

Othman

Bilan

Katz

et al. 2022

ChemElectroChem

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Gold screen printed electrodes (Au-SPEs) were treated electrochemically to produce a micro-rough pattern increasing the real electrode surface. The procedure based on the Dynamic Hydrogen Bubble Template (DHBT) method included electrochemical deposition of Au layers onto the surface of the Au-SPEs, followed by a reductive process at À 3 V (vs. Ag/AgCl) leading to formation of H 2 bubbles, which produced pores in the Au multilayer. The morphology of the micro-porous Au electrode was characterized by scanning electron microscopy (SEM), surface mapping, surface profilometry, and confocal microscopy. The electrode surface morphology was controlled by the time of the electrode reductive treatment (H 2 evolution) and the optimized condition resulting in the best surface structuring was found. Notably, the surface roughness leading to the highest electrode surface area was significantly increased compared to previously reported results with Au-SPEs.

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Defect Levels in Nuclear Detector Grade Cd_0.9Zn_0.1Te Crystals

Cited by 22 publications

References 19 publications

What is Next? Molecular Biology Brings New Ideas

What is Next? Molecular Biology Brings New Ideas

Bioelectrocatalytic Electrodes Modified with PQQ‐Glucose Dehydrogenase‐Calmodulin Chimera Switchable by Peptide Signals: Pathway to Generic Bioelectronic Systems Controlled by Biomolecular Inputs

Highly Porous Gold Electrodes – Preparation and Characterization

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Defect Levels in Nuclear Detector Grade Cd0.9Zn0.1Te Crystals

Cited by 22 publications

References 19 publications

What is Next? Molecular Biology Brings New Ideas

What is Next? Molecular Biology Brings New Ideas

Bioelectrocatalytic Electrodes Modified with PQQ‐Glucose Dehydrogenase‐Calmodulin Chimera Switchable by Peptide Signals: Pathway to Generic Bioelectronic Systems Controlled by Biomolecular Inputs

Highly Porous Gold Electrodes – Preparation and Characterization

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Product

Resources

About

Defect Levels in Nuclear Detector Grade Cd_0.9Zn_0.1Te Crystals