Hemin-binding DNA structures on the surface of bacteria promote extracellular electron transfer DOI Open Access
Obinna M. Ajunwa, Gabriel Antonio S. Minero, Stefan Jensen

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 21, 2024

ABSTRACT Recent research has shown that bacteria in anoxic layers of Pseudomonas aeruginosa biofilms can respire by transferring electrons to oxygen via extracellular DNA (eDNA) and DNA- binding redox mediators are unique this species 1 . In study, we propose a similar but generic mechanism which transfer biofilms, using hemin as redox-mediator hemin-binding G-quadruplex (G4) structures the matrix. Using Staphylococcus epidermidis model organism, voltammetry showed eDNA were needed for electron (EET). Surface-associated G4-DNA formed complex with hemin, transferred from an electrode under conditions. Addition growing promoted EET was stable days. G4-DNA/hemin is also peroxidase-like DNAzyme, capable H 2 O 2. only recently discovered be abundant matrix 2,3 We now show turns these into conduits EET. The study opens door new mechanisms bacterial energy conservation oxygen- limiting conditions, tackling , common host defense against infections.

Language: Английский

Supramolecular assembly-induced electrochemiluminescence enhancement of gold nanoclusters for hemoglobin detection DOI

Xue Ge,

Mingming Zhang, Fei Yin

et al.

Journal of Materials Chemistry B, Journal Year: 2024, Volume and Issue: 12(5), P. 1355 - 1360

Published: Jan. 1, 2024

Gold nanoclusters (Au NCs) with excellent optical properties and biocompatibility have become one of the most promising electrochemiluminescence (ECL) emitters. However, low efficiency poor stability Au NCs restrict their applications in ECL. Herein, by supramolecular assembly L-arginine (Arg) 4-hydroxy-2-mercapto-6-methylpyrimidine (MTU) on surface NCs, Arg/MTU-Au enhanced ECL were prepared. Compared MTU-stabilized (MTU-Au NCs), increased 24.8 times. As a proof-of-concept, sensitive biosensing platform was constructed for detection hemoglobin (Hb) urine using as The proposed provides feasible strategy biomarkers has broad application prospects disease screening clinical marker detection.

Language: Английский

Citations

7
Mechanistic Insights into HRP-Catalyzed Oxidation of the Near-Infrared Fluorescent Dye Sulfo-cyanine 7 DOI Creative Commons
Gabriela Manrique,

Jérémie Gottraux,

Simon Matoori

et al.

ACS Measurement Science Au, Journal Year: 2025, Volume and Issue: 5(1), P. 130 - 134

Published: Jan. 22, 2025

Horseradish peroxidase (HRP) is a widely used enzyme that oxidizes range of substrates in the presence its co-substrate hydrogen peroxide (H2O2). In past, we identified sulfo-cyanine 7 (S7) as novel near-infrared substrate HRP, which loses fluorescence upon enzymatic oxidation peroxide-dependent manner. However, catalytic mechanism and chemical structure products were not well understood. this study, investigate S7 by HRP identify two radical formed during reaction. Our results point to formation non-near-infrared fluorescent species, regeneration S7. These strongly disproportionation reaction was described for other substrates, namely structurally related ABTS (2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid)).

Language: Английский

Citations

0
Catalytic peptide/hemin complex from ester–amide exchange reaction mediated by deep eutectic solvents DOI Creative Commons
C. M. Wang,

Yao-Yu Jhang,

Shengsheng Yu

et al.

RSC Advances, Journal Year: 2025, Volume and Issue: 15(1), P. 119 - 123

Published: Jan. 1, 2025

Peptide libraries generated in deep eutectic solvents lead to peptide/hemin complexes with peroxidase-like activity.

Language: Английский

Citations

0
Optimization and Enhancement of the Peroxidase-like Activity of Hemin in Aqueous Solutions of Sodium Dodecylsulfate DOI Creative Commons
Nemanja Cvjetan, Lukas D. Schuler, Takashi Ishikawa

et al.

ACS Omega, Journal Year: 2023, Volume and Issue: 8(45), P. 42878 - 42899

Published: Nov. 3, 2023

Iron porphyrins play several important roles in present-day living systems and probably already existed very early life forms. Hemin (= ferric protoporphyrin IX = heme b), for example, is the prosthetic group at active site of peroxidases, catalyzing oxidation a number different types reducing substrates after hemin first oxidized by hydrogen peroxide as oxidizing substrate enzyme. The peroxidases consists hydrophobic pocket which embedded noncovalently kept place through coordination iron atom to proximal histidine side chain protein. It this partially local environment enzyme determines efficiency with sequential reactions proceed site. Free hemin, has been separated from protein moiety known aggregate an aqueous solution exhibits low catalytic activity. Based on previous reports use surfactant micelles solubilize free nonaggregated state, peroxidase-like activity presence sodium dodecyl sulfate (SDS) concentrations below above critical concentration SDS micelle formation (critical micellization (cmc)) was systematically investigated. In most experiments, 3,3′,5,5′-tetramethylbenzidine (TMB) applied pH 7.2. clearly had positive effect reaction terms initial rate yield, even cmc. highest correlated cmc value, demonstrated three HEPES concentrations. 4-(2-hydroxyethyl)-1-piperazineethanesulfonate salt (HEPES) served buffer substance also accelerating reaction. At cmc, addition l-histidine (l-His) resulted further concentration-dependent increase until maximal reached optimal l-His concentration, corresponding ideal mono-l-His ligation hemin. Some results obtained can be understood basis molecular dynamics simulations, indicated existence intermolecular interactions between SDS. Preliminary experiments SDS/dodecanol vesicles 7.2 showed that vesicles, exhibited similar case micelles. This supports hypothesis micelle- or vesicle-associated ferrous may have played role primitive catalysts membranous prebiotic compartment before cellular emerged.

Language: Английский

Citations

6
Evaluation of anti-sickling effects of two varieties of Cajanus cajan (L.) Huth on sickle cell beta thalassemia DOI
Eleazar Chukwuemeka Anorue, Parker Elijah Joshua

Journal of Ethnopharmacology, Journal Year: 2024, Volume and Issue: 331, P. 118280 - 118280

Published: May 5, 2024

Language: Английский

Citations

1
Protocellular Heme and Iron–Sulfur Clusters DOI Creative Commons
Daniele Rossetto, Nemanja Cvjetan, Peter Walde

et al.

Accounts of Chemical Research, Journal Year: 2024, Volume and Issue: 57(16), P. 2293 - 2302

Published: Aug. 5, 2024

ConspectusCentral to the quest of understanding emergence life is uncover role metals, particularly iron, in shaping prebiotic chemistry. Iron, as most abundant accessible transition metals on Earth, played a pivotal early biochemical processes and continues be indispensable modern biology. Here, we discuss our recent contributions probing plausibility complexes with including heme iron-sulfur clusters, mediating chemistry beneficial protocell. Laboratory experiments spectroscopic findings suggest plausible pathways, often facilitated by UV light, for synthesis clusters. Once formed, displays catalytic, peroxidase-like activity when complexed amphiphiles. This could have been two ways. First, catalytically removed molecule (H

Language: Английский

Citations

1
Hemin-binding DNA structures on the surface of bacteria promote extracellular electron transfer DOI Open Access
Obinna M. Ajunwa, Gabriel Antonio S. Minero, Stefan Jensen

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 21, 2024

ABSTRACT Recent research has shown that bacteria in anoxic layers of Pseudomonas aeruginosa biofilms can respire by transferring electrons to oxygen via extracellular DNA (eDNA) and DNA- binding redox mediators are unique this species 1 . In study, we propose a similar but generic mechanism which transfer biofilms, using hemin as redox-mediator hemin-binding G-quadruplex (G4) structures the matrix. Using Staphylococcus epidermidis model organism, voltammetry showed eDNA were needed for electron (EET). Surface-associated G4-DNA formed complex with hemin, transferred from an electrode under conditions. Addition growing promoted EET was stable days. G4-DNA/hemin is also peroxidase-like DNAzyme, capable H 2 O 2. only recently discovered be abundant matrix 2,3 We now show turns these into conduits EET. The study opens door new mechanisms bacterial energy conservation oxygen- limiting conditions, tackling , common host defense against infections.

Language: Английский

Citations

0