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Journal of Materials Chemistry. B Sep 2023Platinum-group metal (PGM) nanostructures with peroxidase-like catalytic activities (, peroxidase mimics) have been actively developed and applied to diagnostics in... (Review)
Review
Platinum-group metal (PGM) nanostructures with peroxidase-like catalytic activities (, peroxidase mimics) have been actively developed and applied to diagnostics in recent years. This article provides our viewpoints on this emerging field from the perspectives of materials science and solid-state chemistry angles. We start with an introduction to PGM peroxidase mimics, their catalytic efficiencies, and insights into catalysis from computational simulations. We then discuss chemical approaches to the synthesis of PGM peroxidase mimics with desired physicochemical parameters and catalytic properties. Then, we elaborate on general methods for functionalizing the surfaces of PGM mimics with bioreceptors. Thereafter, we highlight the applications of PGM mimics in diagnostics, emphasizing the interactions of PGM mimics with other components of a diagnostic system. We conclude this article with our opinions on the challenges and opportunities in this field.
Topics: Peroxidase; Platinum; Peroxidases; Catalysis; Coloring Agents
PubMed: 37644782
DOI: 10.1039/d3tb01255g -
Molecules (Basel, Switzerland) Oct 2018The heme in the active center of peroxidases reacts with hydrogen peroxide to form highly reactive intermediates, which then oxidize simple substances called peroxidase... (Review)
Review
The heme in the active center of peroxidases reacts with hydrogen peroxide to form highly reactive intermediates, which then oxidize simple substances called peroxidase substrates. Human peroxidases can be divided into two groups: (1) True peroxidases are enzymes whose main function is to generate free radicals in the peroxidase cycle and (pseudo)hypohalous acids in the halogenation cycle. The major true peroxidases are myeloperoxidase, eosinophil peroxidase and lactoperoxidase. (2) Pseudo-peroxidases perform various important functions in the body, but under the influence of external conditions they can display peroxidase-like activity. As oxidative intermediates, these peroxidases produce not only active heme compounds, but also protein-based tyrosyl radicals. Hemoglobin, myoglobin, cytochrome /cardiolipin complexes and cytoglobin are considered as pseudo-peroxidases. Рeroxidases play an important role in innate immunity and in a number of physiologically important processes like apoptosis and cell signaling. Unfavorable excessive peroxidase activity is implicated in oxidative damage of cells and tissues, thereby initiating the variety of human diseases. Hence, regulation of peroxidase activity is of considerable importance. Since peroxidases differ in structure, properties and location, the mechanisms controlling peroxidase activity and the biological effects of peroxidase products are specific for each hemoprotein. This review summarizes the knowledge about the properties, activities, regulations and biological effects of true and pseudo-peroxidases in order to better understand the mechanisms underlying beneficial and adverse effects of this class of enzymes.
Topics: Catalytic Domain; Eosinophil Peroxidase; Free Radicals; Heme; Humans; Hydrogen Peroxide; Lactoperoxidase; Oxidation-Reduction; Oxidative Stress; Peroxidase; Peroxidases
PubMed: 30297621
DOI: 10.3390/molecules23102561 -
Chemosphere Jan 2024Single-atom nanozymes (SANs) are nanomaterials-based nanozymes with atomically dispersed enzyme-like active sites. SANs offer improved as well as tunable catalytic... (Review)
Review
Single-atom nanozymes (SANs) are nanomaterials-based nanozymes with atomically dispersed enzyme-like active sites. SANs offer improved as well as tunable catalytic activity. The creation of extremely effective SANs and their potential uses have piqued researchers' curiosity due to their advantages of cheap cost, variable catalytic activity, high stability, and large-scale production. Furthermore, SANs with uniformly distributed active centers and definite coordination structures offer a distinctive opportunity to investigate the structure-activity correlation and control the geometric and electrical features of metal centers. SANs have been extensively explored in photo-, thermal-, and electro-catalysis. However, SANs suffer from the following disadvantages, such as efficiency, non-mimicking of the 3-D complexity of natural enzymes, limited and narrow range of artificial SANs, and biosafety aspects. Among a quite limited range of artificial SANs, the peroxidase action of SANs has attracted significant research attention in the last five years with the aim of producing reactive oxygen species for use in cancer therapy, and water treatment among many other applications. In this review, we explore the recent progress of different SANs as peroxidase mimics, the role of the metal center in enzymatic activity, possible prospects, and underlying limitations in real-time applications.
Topics: Biomimetic Materials; Nanostructures; Peroxidase; Catalysis; Peroxidases
PubMed: 38303399
DOI: 10.1016/j.chemosphere.2023.140557 -
Advanced Drug Delivery Reviews Jun 2022Significant progress has been made in developing two-dimensional (2D) nanomaterials owing to their ultra-thin structure, high specific surface area, and many other... (Review)
Review
Significant progress has been made in developing two-dimensional (2D) nanomaterials owing to their ultra-thin structure, high specific surface area, and many other advantages. Recently, 2D nanomaterials with enzyme-like properties, especially peroxidase (POD)-like activity, are highly desirable for many biomedical applications. In this review, we first classify the types of 2D POD-like nanomaterials and then summarize various strategies for endowing 2D nanomaterials with POD-like properties. Representative examples of biomedical applications are reviewed, emphasizing in antibacterial, biosensing, and cancer therapy. Last, the future challenges and prospects of 2D POD-like nanomaterials are discussed. This review is expected to provide an in-depth understanding of 2D POD-like materials for biomedical applications.
Topics: Humans; Nanostructures; Peroxidase; Peroxidases
PubMed: 35398244
DOI: 10.1016/j.addr.2022.114269 -
The Tohoku Journal of Experimental... 1953
Topics: Hormones; Liver; Oxidoreductases; Peroxidase; Peroxidases
PubMed: 13136141
DOI: 10.1620/tjem.58.112 -
Journal of Molecular Medicine (Berlin,... Sep 1998Myeloperoxidase (MPO) belongs to a family of related proteins which also includes eosinophil, thyroid, and lactoperoxidase. The MPO gene is a 14-kb gene located on the... (Review)
Review
Myeloperoxidase (MPO) belongs to a family of related proteins which also includes eosinophil, thyroid, and lactoperoxidase. The MPO gene is a 14-kb gene located on the long arm of chromosome 17. Thus far four mutations (R569W, Y173C, M251T and a 14-base deletion in exon 9) have been identified in patients with MPO deficiency. As in other genetically determined diseases, many more mutations will eventually be revealed that cause this disease. Present evidence shows that most patients are compound heterozygotes, i.e., they have inherited different mutations on their paternal and maternal MPO alleles. Understanding why some patients with this genetic deficiency develop clinical symptoms while others do not requires mutation analyses of a large number of patients. This includes the analysis of genotype-phenotype relationships. Genotyping has also been started in patients with EPO-deficiency.
Topics: Amino Acid Sequence; Base Sequence; DNA Mutational Analysis; Female; Genotype; Humans; Male; Metabolism, Inborn Errors; Molecular Sequence Data; Multigene Family; Peroxidase; Phenotype
PubMed: 9766847
DOI: 10.1007/s001090050269 -
International Journal of Molecular... Jul 2023Oxidases and peroxidases have found application in the field of chlorine-free organic dye degradation in the paper, toothpaste, and detergent industries. Nevertheless,...
Oxidases and peroxidases have found application in the field of chlorine-free organic dye degradation in the paper, toothpaste, and detergent industries. Nevertheless, their widespread use is somehow hindered because of their cost, availability, and batch-to-batch reproducibility. Here, we report the catalytic proficiency of a miniaturized synthetic peroxidase, Fe-Mimochrome VI*a, in the decolorization of four organic dyes, as representatives of either the heterocyclic or triarylmethane class of dyes. Fe-Mimochrome VI*a performed over 130 turnovers in less than five minutes in an aqueous buffer at a neutral pH under mild conditions.
Topics: Peroxidase; Coloring Agents; Reproducibility of Results; Peroxidases; Catalysis
PubMed: 37446248
DOI: 10.3390/ijms241311070 -
Clinica Chimica Acta; International... Jun 2019Myeloperoxidase (MPO) is a member of the superfamily of heme peroxidases that is mainly expressed in neutrophils and monocytes. MPO-derived reactive species play a key... (Review)
Review
Myeloperoxidase (MPO) is a member of the superfamily of heme peroxidases that is mainly expressed in neutrophils and monocytes. MPO-derived reactive species play a key role in neutrophil antimicrobial activity and human defense against various pathogens primarily by participating in phagocytosis. Elevated MPO levels in circulation are associated with inflammation and increased oxidative stress. Multiple lines of evidence suggest an association between MPO and cardiovascular disease (CVD) including coronary artery disease, congestive heart failure, arterial hypertension, pulmonary arterial hypertension, peripheral arterial disease, myocardial ischemia/reperfusion-related injury, stroke, cardiac arrhythmia and venous thrombosis. Elevated MPO levels are associated with a poor prognosis including increased risk for overall and CVD-related mortality. Elevated MPO may signify an increased risk for CVD for at least 2 reasons. First, low-grade inflammation and increased oxidative stress coexist with many metabolic abnormalities and comorbidities and consequently an elevated MPO level may represent an increased cardiometabolic risk in general. Second, MPO produces a large number of highly reactive species which can attack, destroy or modify the function of every known cellular component. The most common MPO actions relevant to CVD are generation of dysfunctional lipoproteins with an increased atherogenicity potential, reduced NO availability, endothelial dysfunction, impaired vasoreactivity and atherosclerotic plaque instability. These actions strongly suggest that MPO is directly involved in the pathophysiology of CVD. In this regard MPO may be seen as a mediator or an instrument through which inflammation promotes CVD at molecular and cellular level. Clinical value of MPO therapeutic inhibition remains to be tested.
Topics: Cardiovascular Diseases; Humans; Inflammation; Oxidative Stress; Peroxidase
PubMed: 30797769
DOI: 10.1016/j.cca.2019.02.022 -
Scientific Reports Aug 2023In recent years, the peroxidase enzymes have generated wide interest in several industrial processes, such as wastewater treatments, food processing, pharmaceuticals,...
In recent years, the peroxidase enzymes have generated wide interest in several industrial processes, such as wastewater treatments, food processing, pharmaceuticals, and the production of fine chemicals. However, the low stability of the peroxidases in the presence of hydrogen peroxide (HO) has limited its commercial use. In the present work, the effect of HO on the inactivation of horseradish peroxidase (HRP) was evaluated. Three states of HRP (E, E, and E) were identified. While in the absence of HO, the resting state E was observed, in the presence of low and high concentrations of HO, E and E were found, respectively. The results showed that HRP catalyzed the HO decomposition, forming the species E, which was catalytically inactive. Results suggest that this loss of enzymatic activity is an intrinsic characteristic of the studied HRP. A model from a modified version of the Dunford mechanism of peroxidases was developed, which was validated against experimental data and findings reported by the literature.
Topics: Horseradish Peroxidase; Hydrogen Peroxide; Kinetics; Peroxidases; Peroxidase
PubMed: 37591893
DOI: 10.1038/s41598-023-39687-1 -
Redox Report : Communications in Free... 2000The first complete mechanistic analysis of halide ion oxidation by a peroxidase was that of iodide oxidation by horseradish peroxidase. It was shown conclusively that a...
The first complete mechanistic analysis of halide ion oxidation by a peroxidase was that of iodide oxidation by horseradish peroxidase. It was shown conclusively that a two-electron oxidation of iodide by compound I was occurring. This implied that oxygen atom transfer was occurring from compound I to iodide, forming hypoiodous acid, HOI. Searches were conducted for other two-electron oxidations. It was found that sulfite was oxidized by a two-electron mechanism. Nitrite and sulfoxides were not. If a competing substrate reduces some compound I to compound II by the usual one-electron route, then compound II will compete for available halide. Thus compound II oxidizes iodide to an iodine atom, I*, although at a slower rate than oxidation of I by compound I. An early hint that mammalian peroxidases were designed for halide ion oxidation was obtained in the reaction of lactoperoxidase compound II with iodide. The reaction was accelerated by excess iodide, indicating a co-operative effect. Among the heme peroxidases, only chloroperoxidase (for example from Caldariomyces fumago) and mammalian myeloperoxidase are able to oxidize chloride ion. There is not yet a consensus as to whether the chlorinating agent produced in a peroxidase-catalyzed reaction is hypochlorous acid (HOCl), enzyme-bound hypochlorous acid (either Fe-HOCl or X-HOCl where X is an amino acid residue), or molecular chlorine Cl2. A study of the nonenzymatic iodination of tyrosine showed that the iodinating reagent was either HOI or I2. It was impossible to tell which species because of the equilibria: [reaction: see text] The same considerations apply to product analysis of an enzyme-catalyzed reaction. Detection of molecular chlorine Cl2 does not prove it is the chlorinating species. If Cl2 is in equilibrium with HOCl then one cannot tell which (if either) is the chlorinating reagent. Examples will be shown of evidence that peroxidase-bound hypochlorous acid is the chlorinating agent. Also a recent clarification of the mechanism of reaction of myeloperoxidase with hydrogen peroxide and chloride along with accurate determination of the elementary rate constants will be discussed.
Topics: Animals; Catalysis; Chlorine; Humans; Hydrogen Peroxide; Iodine; Oxidation-Reduction; Peroxidase; Peroxidases
PubMed: 10994869
DOI: 10.1179/135100000101535708