Enzymatic activity mastered by altering metal coordination spheres

Moura, Isabel; Pauleta, Sofia R.; Moura, José J. G.

doi:10.1007/s00775-008-0414-3

Cited by 24 publications

(15 citation statements)

References 73 publications

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“…The reduction potentials of the heme groups have been reported in the +0.2 to +0.3 V range [201][202][203]. Upon reduction of the enzyme, the catalytic heme d 1 adopts a 5c configuration capable of binding the nitrite substrate [204,205]. ccNiRs catalyze the six-electron reduction of nitrite to ammonium (Equation ( 14)).…”

Section: Nitrite Reductasesmentioning

confidence: 99%

Electrocatalysis by Heme Enzymes—Applications in Biosensing

et al. 2021

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Heme proteins take part in a number of fundamental biological processes, including oxygen transport and storage, electron transfer, catalysis and signal transduction. The redox chemistry of the heme iron and the biochemical diversity of heme proteins have led to the development of a plethora of biotechnological applications. This work focuses on biosensing devices based on heme proteins, in which they are electronically coupled to an electrode and their activity is determined through the measurement of catalytic currents in the presence of substrate, i.e., the target analyte of the biosensor. After an overview of the main concepts of amperometric biosensors, we address transduction schemes, protein immobilization strategies, and the performance of devices that explore reactions of heme biocatalysts, including peroxidase, cytochrome P450, catalase, nitrite reductase, cytochrome c oxidase, cytochrome c and derived microperoxidases, hemoglobin, and myoglobin. We further discuss how structural information about immobilized heme proteins can lead to rational design of biosensing devices, ensuring insights into their efficiency and long-term stability.

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Section: Nitrite Reductasesmentioning

confidence: 99%

Electrocatalysis by Heme Enzymes—Applications in Biosensing

et al. 2021

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“…These tune the Cu 2+ /Cu + couple redox potential to that required to catalyse the net SOD reaction. This is the way in which different types of enzymes can “tune” the same metal ion for different reactions [ 26 ]. The Mn 3+ /Mn 2+ couple is tuned by the protein ligands in SOD-2 to catalyse the net SOD reaction.…”

Section: Superoxide Dismutasementioning

confidence: 99%

Antioxidant and Metal Chelation-Based Therapies in the Treatment of Prion Disease

2014

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Many neurodegenerative disorders involve the accumulation of multimeric assemblies and amyloid derived from misfolded conformers of constitutively expressed proteins. In addition, the brains of patients and experimental animals afflicted with prion disease display evidence of heightened oxidative stress and damage, as well as disturbances to transition metal homeostasis. Utilising a variety of disease model paradigms, many laboratories have demonstrated that copper can act as a cofactor in the antioxidant activity displayed by the prion protein while manganese has been implicated in the generation and stabilisation of disease-associated conformers. This and other evidence has led several groups to test dietary and chelation therapy-based regimens to manipulate brain metal concentrations in attempts to influence the progression of prion disease in experimental mice. Results have been inconsistent. This review examines published data on transition metal dyshomeostasis, free radical generation and subsequent oxidative damage in the pathogenesis of prion disease. It also comments on the efficacy of trialed therapeutics chosen to combat such deleterious changes.

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“…A coordination position is considered free if it is occupied by a water molecule, which is a weak ligand that can be easily replaced. 13 , 14 However, some enzymes require the water coordination to act as a nucleophile at the active site upon activation. 15 …”

Section: Introductionmentioning

confidence: 99%

“…Studies suggest that some enzymes are active (ready to react with the substrate) due to a vacant coordination position at the metal center. A coordination position is considered free if it is occupied by a water molecule, which is a weak ligand that can be easily replaced. , However, some enzymes require the water coordination to act as a nucleophile at the active site upon activation …”

Section: Introductionmentioning

confidence: 99%

Metal-Ion Effects on the Polarization of Metal-Bound Water and Infrared Vibrational Modes of the Coordinated Metal Center of Mycobacterium tuberculosis Pyrazinamidase via Quantum Mechanical Calculations

et al. 2014

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Mycobacterium tuberculosis pyrazinamidase (PZAse) is a key enzyme to activate the pro-drug pyrazinamide (PZA). PZAse is a metalloenzyme that coordinates in vitro different divalent metal cofactors in the metal coordination site (MCS). Several metals including Co2+, Mn2+, and Zn2+ are able to reactivate the metal-depleted PZAse in vitro. We use quantum mechanical calculations to investigate the Zn2+, Fe2+, and Mn2+ metal cofactor effects on the local MCS structure, metal–ligand or metal–residue binding energy, and charge distribution. Results suggest that the major metal-dependent changes occur in the metal–ligand binding energy and charge distribution. Zn2+ shows the highest binding energy to the ligands (residues). In addition, Zn2+ and Mn2+ within the PZAse MCS highly polarize the O–H bond of coordinated water molecules in comparison with Fe2+. This suggests that the coordination of Zn2+ or Mn2+ to the PZAse protein facilitates the deprotonation of coordinated water to generate a nucleophile for catalysis as in carboxypeptidase A. Because metal ion binding is relevant to enzymatic reaction, identification of the metal binding event is important. The infrared vibrational mode shift of the C=Nε (His) bond from the M. tuberculosis MCS is the best IR probe to metal complexation.

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Enzymatic activity mastered by altering metal coordination spheres

Cited by 24 publications

References 73 publications

Electrocatalysis by Heme Enzymes—Applications in Biosensing

Electrocatalysis by Heme Enzymes—Applications in Biosensing

Antioxidant and Metal Chelation-Based Therapies in the Treatment of Prion Disease

Metal-Ion Effects on the Polarization of Metal-Bound Water and Infrared Vibrational Modes of the Coordinated Metal Center of Mycobacterium tuberculosis Pyrazinamidase via Quantum Mechanical Calculations

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