scholarly journals Correction: Photoinduced electron transfer of poly(o-phenylenediamine)–rhodamine B copolymer dots: application in ultrasensitive detection of nitrite in vitro

2017 ◽  
Vol 5 (3) ◽  
pp. 1311-1311
Author(s):  
Fang Liao ◽  
Xun Song ◽  
Siwei Yang ◽  
Chenyao Hu ◽  
Lin He ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Rhodamine B ◽  
Photoinduced Electron Transfer ◽  
Ultrasensitive Detection

Correction for ‘Photoinduced electron transfer of poly(o-phenylenediamine)–rhodamine B copolymer dots: application in ultrasensitive detection of nitrite in vivo’ by Fang Liao et al., J. Mater. Chem. A, 2015, 3, 7568–7574.

Photoinduced electron transfer of poly(o-phenylenediamine)–Rhodamine B copolymer dots: application in ultrasensitive detection of nitrite in vivo

2015 ◽  
Vol 3 (14) ◽  
pp. 7568-7574 ◽  
Author(s):  
Fang Liao ◽  
Xun Song ◽  
Siwei Yang ◽  
Chenyao Hu ◽  
Lin He ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Rhodamine B ◽  
Photoinduced Electron Transfer ◽  
Ultrasensitive Detection ◽  
Fluorescence Sensing ◽  
Sensing System

An ultrasensitive fluorescence sensing system for NO2−in vivo based on photoinduced electron transfer of poly(o-phenylenediamine)–Rhodamine B copolymer dots is built.

scholarly journals Photoactivation of Cryptochromes Invokes Competing Inter- and Intramolecular Electron Transfer

2020 ◽  
Author(s):  
Ruslan N. Tazhigulov ◽  
Justin Provazza ◽  
David Coker ◽  
Ksenia B. Bravaya
Keyword(s):  
Electron Transfer ◽  
Photoinduced Electron Transfer ◽  
Migratory Birds ◽  
Intramolecular Electron Transfer ◽  
Tryptophan Residues ◽  
Theoretical Evidence ◽  
Excited Charge Transfer State

<div>Growing experimental and theoretical evidence points to the key role of cryptochrome proteins in magnetoreception by migratory birds and insects. Cryptochrome photoactivation is achieved through a cascade of electron transfer events leading to formation of a long-lived spin-correlated radical pair. The electron transfer cascade is initiated by photoexcitation of the FAD cofactor and subsequent electron transfer through three conserved tryptophan residues, the so-called tryptophan triad. Presence of ATP was shown to increase the yield of the semireduced form of FAD. While electron transfer through the tryptophan triad is well characterized by both theoretical and experimental methods, the effects of ATP binding are still not well understood. The present work aims to unravel the mechanism of ultrafast photoinduced electron transfer in a cryptochrome protein with a focus on effects of ATP on the FAD photoreduction process. Photoinduced electron transfer is described by means of state-of-the-art theoretical methods: a hybrid quantum-classical polarizable embedding scheme is utilized to accurately parameterize a generalized local excited/charge transfer state system-bath model Hamiltonian and the photoinduced electron transfer process is described by a semiclassical path integral-based dynamics method. The results draw attention to the crucial role of the intramolecular electron transfer from adenine to the flavin moiety of the FAD cofactor for formation of the semireduced form of FAD, providing an explanation for the increased yield of the semireduced form in the presence of the cellular metabolites <i>in vitro</i> and <i>in vivo</i>.</div>

scholarly journals Photoactivation of Cryptochromes Invokes Competing Inter- and Intramolecular Electron Transfer

2020 ◽  
Author(s):  
Ruslan N. Tazhigulov ◽  
Justin Provazza ◽  
David Coker ◽  
Ksenia B. Bravaya
Keyword(s):  
Electron Transfer ◽  
Photoinduced Electron Transfer ◽  
Migratory Birds ◽  
Intramolecular Electron Transfer ◽  
Tryptophan Residues ◽  
Theoretical Evidence ◽  
Excited Charge Transfer State

<div>Growing experimental and theoretical evidence points to the key role of cryptochrome proteins in magnetoreception by migratory birds and insects. Cryptochrome photoactivation is achieved through a cascade of electron transfer events leading to formation of a long-lived spin-correlated radical pair. The electron transfer cascade is initiated by photoexcitation of the FAD cofactor and subsequent electron transfer through three conserved tryptophan residues, the so-called tryptophan triad. Presence of ATP was shown to increase the yield of the semireduced form of FAD. While electron transfer through the tryptophan triad is well characterized by both theoretical and experimental methods, the effects of ATP binding are still not well understood. The present work aims to unravel the mechanism of ultrafast photoinduced electron transfer in a cryptochrome protein with a focus on effects of ATP on the FAD photoreduction process. Photoinduced electron transfer is described by means of state-of-the-art theoretical methods: a hybrid quantum-classical polarizable embedding scheme is utilized to accurately parameterize a generalized local excited/charge transfer state system-bath model Hamiltonian and the photoinduced electron transfer process is described by a semiclassical path integral-based dynamics method. The results draw attention to the crucial role of the intramolecular electron transfer from adenine to the flavin moiety of the FAD cofactor for formation of the semireduced form of FAD, providing an explanation for the increased yield of the semireduced form in the presence of the cellular metabolites <i>in vitro</i> and <i>in vivo</i>.</div>

scholarly journals Evaluation of the electron transfer flavoprotein as an antibacterial target in Burkholderia cenocepacia

2017 ◽  
Vol 63 (10) ◽  
pp. 857-863 ◽  
Author(s):  
Maria S. Stietz ◽  
Christina Lopez ◽  
Osasumwen Osifo ◽  
Marcelo E. Tolmasky ◽  
Silvia T. Cardona
Keyword(s):  
Electron Transfer ◽  
Burkholderia Cepacia ◽  
Multidrug Resistant ◽  
Burkholderia Cenocepacia ◽  
Burkholderia Cepacia Complex ◽  
Infection Model ◽  
Electron Transfer Flavoprotein ◽  
C Elegans

There are hundreds of essential genes in multidrug-resistant bacterial genomes, but only a few of their products are exploited as antibacterial targets. An example is the electron transfer flavoprotein (ETF), which is required for growth and viability in Burkholderia cenocepacia. Here, we evaluated ETF as an antibiotic target for Burkholderia cepacia complex (Bcc). Depletion of the bacterial ETF during infection of Caenorhabditis elegans significantly extended survival of the nematodes, proving that ETF is essential for survival of B. cenocepacia in this host model. In spite of the arrest in respiration in ETF mutants, the inhibition of etf expression did not increase the formation of persister cells, when treated with high doses of ciprofloxacin or meropenem. To test if etf translation could be inhibited by RNA interference, antisense oligonucleotides that target the etfBA operon were synthesized. One antisense oligonucleotide was effective in inhibiting etfB translation in vitro but not in vivo, highlighting the challenge of reduced membrane permeability for the design of drugs against B. cenocepacia. This work contributes to the validation of ETF of B. cenocepacia as a target for antibacterial therapy and demonstrates the utility of a C. elegans liquid killing assay to validate gene essentiality in an in vivo infection model.

In Vitro Evaluation of Miniaturized Amperometric Enzyme Sensor Based on the Direct Electron Transfer Principle for Continuous Glucose Monitoring

2022 ◽  
pp. 193229682110706
Author(s):  
Yutaro Inoue ◽  
Yasuhide Kusaka ◽  
Kotaro Shinozaki ◽  
Inyoung Lee ◽  
Koji Sode
Keyword(s):  
Electron Transfer ◽  
Continuous Glucose Monitoring ◽  
Glucose Sensor ◽  
Direct Electron Transfer ◽  
Glucose Dehydrogenase ◽  
Glucose Monitoring ◽  
Reference Electrode ◽  
Enzyme Sensor

Background: The bacterial derived flavin adenine dinucleotide (FAD)-dependent glucose dehydrogenase (FADGDH) is the most promising enzyme for the third-generation principle-based enzyme sensor for continuous glucose monitoring (CGM). Due to the ability of the enzyme to transfer electrons directly to the electrode, recognized as direct electron transfer (DET)-type FADGDH, although no investigation has been reported about DET-type FADGDH employed on a miniaturized integrated electrode. Methods: The miniaturized integrated electrode was formed by sputtering gold (Au) onto a flexible film with 0.1 mm in thickness and divided into 3 parts. After an insulation layer was laminated, 3 openings for a working electrode, a counter electrode and a reference electrode were formed by dry etching. A reagent mix containing 1.2 × 10−4 Unit of DET-type FADGDH and carbon particles was deposited. The long-term stability of sensor was evaluated by continuous operation, and its performance was also evaluated in the presence of acetaminophen and the change in oxygen partial pressure (pO2) level. Results: The amperometric response of the sensor showed a linear response to glucose concentration up to 500 mg/dL without significant change of the response over an 11-day continuous measurement. Moreover, the effect of acetaminophen and pO2 on the response were negligible. Conclusions: These results indicate the superb potential of the DET-type FADGDH-based sensor with the combination of a miniaturized integrated electrode. Thus, the described miniaturized DET-type glucose sensor for CGM will be a promising tool for effective glycemic control. This will be further investigated using an in vivo study.

Bioconversion of Carbon Monoxide to Formate Using Artificially Designed Carbon Monoxide:Formate Oxidoreductase in Hyperthermophilic Archaea

2021 ◽  
Author(s):  
Jae Kyu Lim ◽  
Ji-In Yang ◽  
Yun Jae Kim ◽  
Yeong-Jun Park ◽  
Yong Hwan Kim
Keyword(s):  
Carbon Monoxide ◽  
Electron Transfer ◽  
Fusion Protein ◽  
Direct Electron Transfer ◽  
Co2 Reduction ◽  
Hyperthermophilic Archaea ◽  
Production Activity ◽  
Formate Production

Abstract Ferredoxin-dependent metabolic engineering of electron transfer circuits has been developed to enhance redox efficiency in the field of synthetic biology, e.g., for hydrogen production and for reduction of flavoproteins or NAD(P)+. Here, we present the bioconversion of carbon monoxide (CO) gas to formate via a synthetic CO:formate oxidoreductase (CFOR), designed as an enzyme complex for direct electron transfer between noninteracting CO dehydrogenase and formate dehydrogenase using an electron-transferring Fe-S fusion protein. The CFOR-introduced Thermococcus onnurineus mutant strains showed CO-dependent formate production in vivo and in vitro. The formate production rate from purified CFOR complex and specific formate productivity from the bioreactor were 348 ± 34 μmol/mg/min and 90.2 ± 20.4 mmol/g-cells/h, respectively. The CO-dependent CO2 reduction/formate production activity of synthetic CFOR was confirmed, indicating that direct electron transfer between two unrelated dehydrogenases was feasible via mediation of the FeS-FeS fusion protein.

scholarly journals A rhodamine-based chemosensor with diphenylselenium for highly selective fluorescence turn-on detection of Hg2+in vitro and in vivo

RSC Advances ◽  
2017 ◽  
Vol 7 (35) ◽  
pp. 21733-21739 ◽  
Author(s):  
Parthiban Venkatesan ◽  
Natesan Thirumalivasan ◽  
Shu-Pao Wu
Keyword(s):  
Rhodamine B ◽  
Turn On ◽  
Fluorescence Turn On

A rhodamine-B based chemosensor with diphenylselenium, RhoSe, has been developed for highly selective fluorescent turn-on detection of Hg2+.

Sign in / Sign up

Export Citation Format

Share Document