-
Sensors (Basel, Switzerland) Sep 2021Hypochlorous acid (HOCl) generates from the reaction between hydrogen peroxide and chloride ions via myeloperoxidase (MPO)-mediated in vivo. As very important reactive... (Review)
Review
Hypochlorous acid (HOCl) generates from the reaction between hydrogen peroxide and chloride ions via myeloperoxidase (MPO)-mediated in vivo. As very important reactive oxygen species (ROS), hypochlorous acid (HOCl)/hypochlorite (OCl) play a crucial role in a variety of physiological and pathological processes. However, excessive or misplaced production of HOCl/OCl can cause variety of tissue damage and human diseases. Therefore, rapid, sensitive, and selective detection of OCl is very important. In recent years, the fluorescent probe method for detecting hypochlorous acid has been developed rapidly due to its simple operation, low toxicity, high sensitivity, and high selectivity. In this review, the progress of recently discovered fluorescent probes for the detection of hypochlorous acid was summarized with the aim to provide useful information for further design of better fluorescent probes.
Topics: Fluorescent Dyes; Humans; Hydrogen Peroxide; Hypochlorous Acid; Peroxidase
PubMed: 34640646
DOI: 10.3390/s21196326 -
Journal of Microbiology and... Jan 2021γ-Glutamylcysteine synthetase (Gcs1) and glutathione reductase (Glr1) activity maintains minimal levels of cellular methylglyoxal in . In glutathione-depleted , we...
γ-Glutamylcysteine synthetase (Gcs1) and glutathione reductase (Glr1) activity maintains minimal levels of cellular methylglyoxal in . In glutathione-depleted , we previously saw that NAD(H)-linked methylglyoxal oxidoreductase (Mgd1) and alcohol dehydrogenase (Adh1) are the most active methylglyoxal scavengers. With methylglyoxal accumulation, disruptants lacking or exhibit a poor redox state. However, there is little convincing evidence for a reciprocal relationship between methylglyoxal scavenger genes-disrupted mutants and changes in glutathione-(in)dependent redox regulation. Herein, we attempt to demonstrate a functional role for methylglyoxal scavengers, modeled on a triple disruptant (//), to link between antioxidative enzyme activities and their metabolites in glutathione-depleted conditions. Despite seeing elevated methylglyoxal in all of the disruptants, the result saw a decrease in pyruvate content in // which was not observed in double gene-disrupted strains such as / and /. Interestingly, // exhibited a significantly decrease in HO and superoxide which was also unobserved in / and /. The activities of the antioxidative enzymes erythroascorbate peroxidase and cytochrome c peroxidase were noticeably higher in // than in the other disruptants. Meanwhile, Glr1 activity severely diminished in //. Monitoring complementary gene transcripts between double gene-disrupted / and / supported the concept of an unbalanced redox state independent of the Glr1 activity for //. Our data demonstrate the reciprocal use of Eapx1 and Ccp1 in the absence of both methylglyoxal scavengers; that being pivotal for viability in non-filamentous budding yeast.
Topics: Alcohol Dehydrogenase; Candida albicans; Cytochrome-c Peroxidase; Enzyme Assays; Fungal Proteins; Genes, Fungal; Glutamate-Cysteine Ligase; Glutathione; Hydrogen Peroxide; Oxidation-Reduction; Oxidoreductases; Peroxidase; Peroxidases; Pyruvaldehyde; Saccharomyces cerevisiae Proteins; Superoxides
PubMed: 33203822
DOI: 10.4014/jmb.2010.10057 -
International Journal of Molecular... Sep 2022This review discusses the formation of hypochlorous acid HOCl and the role of reactive chlorinated species (RCS), which are catalysed by the enzyme myeloperoxidase MPO,... (Review)
Review
This review discusses the formation of hypochlorous acid HOCl and the role of reactive chlorinated species (RCS), which are catalysed by the enzyme myeloperoxidase MPO, mainly located in leukocytes and which in turn contribute to cellular oxidative stress. The reactions of RCS with various organic molecules such as amines, amino acids, proteins, lipids, carbohydrates, nucleic acids, and DNA are described, and an attempt is made to explain the chemical mechanisms of the formation of the various chlorinated derivatives and the data available so far on the effects of MPO, RCS and halogenative stress. Their presence in numerous pathologies such as atherosclerosis, arthritis, neurological and renal diseases, diabetes, and obesity is reviewed and were found to be a feature of debilitating diseases.
Topics: Amines; Amino Acids; Animals; Carbohydrates; Hypochlorous Acid; Lipids; Mammals; Nucleic Acids; Peroxidase
PubMed: 36142645
DOI: 10.3390/ijms231810735 -
Microbiology Spectrum Feb 2022Heme-containing peroxidases are widely distributed in the animal and plant kingdoms and play an important role in host defense by generating potent oxidants....
Heme-containing peroxidases are widely distributed in the animal and plant kingdoms and play an important role in host defense by generating potent oxidants. Myeloperoxidase (MPO), the prototype of heme-containing peroxidases, exists in neutrophils and monocytes. MPO has a broad spectrum of microbial killing. The difficulty of producing MPO at a large scale hinders its study and utilization. This study aimed to overexpress recombinant human MPO and characterize its microbicidal activities and . A human HEK293 cell line stably expressing recombinant MPO (rMPO) was established as a component of this study. rMPO was overexpressed and purified for studies on its biochemical and enzymatic properties, as well as its microbicidal activities. In this study, rMPO was secreted into culture medium as a monomer. rMPO revealed enzymatic activity similar to that of native MPO. rMPO, like native MPO, was capable of killing a broad spectrum of microorganisms, including Gram-negative and -positive bacteria and fungi, at low nM levels. Interestingly, rMPO could kill antibiotic-resistant bacteria, making it very useful for treatment of nosocomial infections and mixed infections. The administration of rMPO significantly reduced the morbidity and mortality of murine lung infections induced by Pseudomonas aeruginosa or methicillin-resistant Staphylococcus aureus. In animal safety tests, the administration of 100 nM rMPO via tail vein did not result in any sign of toxic effects. Taken together, the data suggest that rMPO purified from a stably expressing human cell line is a new class of antimicrobial agents with the ability to kill a broad spectrum of pathogens, including bacteria and fungi with or without drug resistance. Over the past 2 decades, more than 20 new infectious diseases have emerged. Unfortunately, novel antimicrobial therapeutics are discovered at much lower rates. Infections caused by resistant microorganisms often fail to respond to conventional treatment, resulting in prolonged illness, greater risk of death, and high health care costs. Currently, this is best seen with the lack of a cure for coronavirus disease 2019 (COVID-19). To combat such untreatable microorganisms, there is an urgent need to discover new classes of antimicrobial agents. Myeloperoxidase (MPO) plays an important role in host defense. The difficulty of producing MPO on a large scale hinders its study and utilization. We have produced recombinant MPO at a large scale and have characterized its antimicrobial activities. Most importantly, recombinant MPO significantly reduced the morbidity and mortality of murine pneumonia induced by Pseudomonas aeruginosa or methicillin-resistant Staphylococcus aureus. Our data suggest that recombinant MPO from human cells is a new class of antimicrobials with a broad spectrum of activity.
Topics: Acute Disease; Animals; Anti-Infective Agents; Candida albicans; Drug Resistance, Bacterial; Escherichia coli; Female; HEK293 Cells; Humans; Hydrogen Peroxide; Male; Methicillin-Resistant Staphylococcus aureus; Mice; Mice, Inbred C57BL; Peroxidase; Pneumonia, Bacterial; Pseudomonas Infections; Pseudomonas aeruginosa; Recombinant Proteins; Staphylococcal Infections; Staphylococcus aureus
PubMed: 35019674
DOI: 10.1128/spectrum.00522-21 -
Journal of Leukocyte Biology Apr 2016Myeloperoxidase aids in clearance of microbes by generation of peroxidase-mediated oxidants that kill leukocyte-engulfed pathogens. In this review, we will examine 1)... (Review)
Review
Myeloperoxidase aids in clearance of microbes by generation of peroxidase-mediated oxidants that kill leukocyte-engulfed pathogens. In this review, we will examine 1) strategies for in vitro evaluation of myeloperoxidase function and its inhibition, 2) ways to monitor generation of certain oxidant species during inflammation, and 3) how these methods can be used to approximate the total polymorphonuclear neutrophil chemotaxis following insult. Several optical imaging probes are designed to target reactive oxygen and nitrogen species during polymorphonuclear neutrophil inflammatory burst following injury. Here, we review the following 1) the broad effect of myeloperoxidase on normal physiology, 2) the difference between myeloperoxidase and other peroxidases, 3) the current optical probes available for use as surrogates for direct measures of myeloperoxidase-derived oxidants, and 4) the range of preclinical options for imaging myeloperoxidase accumulation at sites of inflammation in mice. We also stress the advantages and drawbacks of each of these methods, the pharmacokinetic considerations that may limit probe use to strictly cell cultures for some reactive oxygen and nitrogen species, rather than in vivo utility as indicators of myeloperoxidase function. Taken together, our review should shed light on the fundamental rational behind these techniques for measuring myeloperoxidase activity and polymorphonuclear neutrophil response after injury toward developing safe myeloperoxidase inhibitors as potential therapy for chronic obstructive pulmonary disease and rheumatoid arthritis.
Topics: Animals; Humans; Inflammation; Mice; Neutrophils; Peroxidase; Reactive Nitrogen Species; Reactive Oxygen Species; Respiratory Burst
PubMed: 26884610
DOI: 10.1189/jlb.3RU0615-256R -
Gut Microbes 2022This study investigates the interplay between Lon protease and catalase-peroxidase (KatG) in relation to virulence modulation and the response to oxidative stress in...
This study investigates the interplay between Lon protease and catalase-peroxidase (KatG) in relation to virulence modulation and the response to oxidative stress in Typhimurium (ST). Proteomic comparison of ST wild-type and deletion mutant led to the recognition of a highly expressed KatG protein product among five other protein candidates that were significantly affected by deletion. By employing a bacterium two-hybrid assay (B2H), we demonstrated that the catalytic domain of Lon protease potentially interacts with the KatG protein that leads to proteolytic cleavage. Assessment of virulence gene expression in single and double and mutants revealed to be a potential positive modulator of both pathogenicity Island-1 (SPI-1) and -2, while significantly affected SPI-1 genes. ST double deletion mutant, ∆ was more susceptible to survival defects within macrophage-like cells and exhibited meager colonization of the mouse spleen compared to the single deletion mutants. The findings reveal a previously unknown function of Lon and KatG interaction in virulence. Taken together, our experiments demonstrate the importance of Lon and KatG to cope with oxidative stress, for intracellular survival and virulence of .
Topics: Animals; Bacterial Proteins; Catalase; Gastrointestinal Microbiome; Gene Expression Regulation, Bacterial; Mice; Oxidative Stress; Peroxidase; Protease La; Proteomics; Salmonella Infections; Salmonella typhimurium; Virulence
PubMed: 35438052
DOI: 10.1080/19490976.2022.2064705 -
Journal of the American Society of... Nov 2018Goodpasture syndrome (GP) is a pulmonary-renal syndrome characterized by autoantibodies directed against the NC1 domains of collagen IV in the glomerular and alveolar...
BACKGROUND
Goodpasture syndrome (GP) is a pulmonary-renal syndrome characterized by autoantibodies directed against the NC1 domains of collagen IV in the glomerular and alveolar basement membranes. Exposure of the cryptic epitope is thought to occur disruption of sulfilimine crosslinks in the NC1 domain that are formed by peroxidasin-dependent production of hypobromous acid. Peroxidasin, a heme peroxidase, has significant structural overlap with myeloperoxidase (MPO), and MPO-ANCA is present both before and at GP diagnosis in some patients. We determined whether autoantibodies directed against peroxidasin are also detected in GP.
METHODS
We used ELISA and competitive binding assays to assess the presence and specificity of autoantibodies in serum from patients with GP and healthy controls. Peroxidasin activity was fluorometrically measured in the presence of partially purified IgG from patients or controls. Clinical disease severity was gauged by Birmingham Vasculitis Activity Score.
RESULTS
We detected anti-peroxidasin autoantibodies in the serum of patients with GP before and at clinical presentation. Enriched anti-peroxidasin antibodies inhibited peroxidasin-mediated hypobromous acid production . The anti-peroxidasin antibodies recognized peroxidasin but not soluble MPO. However, these antibodies did crossreact with MPO coated on the polystyrene plates used for ELISAs. Finally, peroxidasin-specific antibodies were also found in serum from patients with anti-MPO vasculitis and were associated with significantly more active clinical disease.
CONCLUSIONS
Anti-peroxidasin antibodies, which would previously have been mischaracterized, are associated with pulmonary-renal syndromes, both before and during active disease, and may be involved in disease activity and pathogenesis in some patients.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Anti-Glomerular Basement Membrane Disease; Antibodies, Antineutrophil Cytoplasmic; Antibody Specificity; Autoantibodies; Autoantigens; Child; Cohort Studies; Collagen Type IV; Extracellular Matrix Proteins; Female; Glomerulonephritis; Hemorrhage; Humans; Lung Diseases; Male; Middle Aged; Models, Immunological; Peroxidase; Peroxidases; Young Adult; Peroxidasin
PubMed: 30279272
DOI: 10.1681/ASN.2018050519 -
Biochimica Et Biophysica Acta. Proteins... Jan 2020Human peroxidasin 1 is a multidomain peroxidase situated in the basement membrane. The iron enzyme with covalently bound heme oxidizes bromide to hypobromous acid which...
Human peroxidasin 1 is a multidomain peroxidase situated in the basement membrane. The iron enzyme with covalently bound heme oxidizes bromide to hypobromous acid which facilitates the formation of distinct sulfilimine cross-links in the collagen IV network and therefore contributes to its mechanical stability. Additional to the catalytically active peroxidase domain peroxidasin comprises a leucine rich repeat domain, four Ig domains and a C-terminal von Willebrand factor type C module (VWC). Peroxidasin has been shown to form homotrimers involving two redox-sensitive cysteine residues and to undergo posttranslational C-terminal proteolytic cleavage. The present study on several recombinantly produced truncated peroxidasin variants showed that the VWC is not required for trimer formation whereas the alpha-helical linker region located between the peroxidase domain and the VWC is crucial for trimerization. Our data furthermore implies that peroxidasin oligomerization occurs intracellularly before C-terminal cleavage. For the first time we present overall solution structures of monomeric and trimeric truncated peroxidasin variants which were determined by rotary shadowing combined with transmission electron microscopy and by small-angle X-ray scattering (SAXS). A triangular arrangement of the peroxidase domains to each other within the homotrimer was revealed and this structure was confirmed by a model of trimeric peroxidase domains. Our SAXS data showed that the Ig domains are highly flexible and interact with the peroxidase domain and that within the homotrimer each alpha-helical linker region interacts with the respective adjacent peroxidase domain. The implications of our findings on the structure-function relationship of peroxidasin are discussed.
Topics: Extracellular Matrix Proteins; Humans; Models, Molecular; Peroxidase; Protein Multimerization; Recombinant Proteins; Peroxidasin
PubMed: 31295557
DOI: 10.1016/j.bbapap.2019.07.002 -
International Journal of Molecular... Oct 2022Myeloperoxidase (MPO) is one of the most abundantly expressed proteins in neutrophils. It serves as a critical component of the antimicrobial defense system,... (Review)
Review
Myeloperoxidase (MPO) is one of the most abundantly expressed proteins in neutrophils. It serves as a critical component of the antimicrobial defense system, facilitating microbial killing via generation of reactive oxygen species (ROS). Interestingly, emerging evidence indicates that in addition to the well-recognized canonical antimicrobial function of MPO, it can directly or indirectly impact immune cells and tissue responses in homeostatic and disease states. Here, we highlight the emerging non-canonical functions of MPO, including its impact on neutrophil longevity, activation and trafficking in inflammation, its interactions with other immune cells, and how these interactions shape disease outcomes. We further discuss MPO interactions with barrier forming endothelial and epithelial cells, specialized cells of the central nervous system (CNS) and its involvement in cancer progression. Such diverse function and the MPO association with numerous inflammatory disorders make it an attractive target for therapies aimed at resolving inflammation and limiting inflammation-associated tissue damage. However, while considering MPO inhibition as a potential therapy, one must account for the diverse impact of MPO activity on various cellular compartments both in health and disease.
Topics: Humans; Peroxidase; Reactive Oxygen Species; Inflammation; Neutrophils; Neoplasms
PubMed: 36293108
DOI: 10.3390/ijms232012250 -
Signal Transduction and Targeted Therapy Mar 2022The current feasibility of nanocatalysts in clinical anti-infection therapy, especially for drug-resistant bacteria infection is extremely restrained because of the...
The current feasibility of nanocatalysts in clinical anti-infection therapy, especially for drug-resistant bacteria infection is extremely restrained because of the insufficient reactive oxygen generation. Herein, a novel Ag/BiMoO (Ag/BMO) nanozyme optimized by charge separation engineering with photoactivated sustainable peroxidase-mimicking activities and NIR-II photodynamic performance was synthesized by solvothermal reaction and photoreduction. The Ag/BMO nanozyme held satisfactory bactericidal performance against methicillin-resistant Staphylococcus aureus (MRSA) (~99.9%). The excellent antibacterial performance of Ag/BMO NPs was ascribed to the corporation of peroxidase-like activity, NIR-II photodynamic behavior, and acidity-enhanced release of Ag. As revealed by theoretical calculations, the introduction of Ag to BMO made it easier to separate photo-triggered electron-hole pairs for ROS production. And the conduction and valence band potentials of Ag/BMO NPs were favorable for the reduction of O to ·O. Under 1064 nm laser irradiation, the electron transfer to BMO was beneficial to the reversible change of Mo/Mo, further improving the peroxidase-like catalytic activity and NIR-II photodynamic performance based on the Russell mechanism. In vivo, the Ag/BMO NPs exhibited promising therapeutic effects towards MRSA-infected wounds. This study enriches the nanozyme research and proves that nanozymes can be rationally optimized by charge separation engineering strategy.
Topics: Anti-Bacterial Agents; Bacteria; Hydrogen-Ion Concentration; Methicillin-Resistant Staphylococcus aureus; Peroxidase; Photochemotherapy
PubMed: 35342192
DOI: 10.1038/s41392-022-00900-8