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Archives of Biochemistry and Biophysics Sep 2022Accompanying the autoxidation of hydroxylamine at pH 10.2, nitroblue tetrazolium was reduced and nitrite was produced in the presence of EDTA. The rate of autoxidation...
Accompanying the autoxidation of hydroxylamine at pH 10.2, nitroblue tetrazolium was reduced and nitrite was produced in the presence of EDTA. The rate of autoxidation was negligible below pH 8.0, but sharply increased with increasing pH. The reduction of nitroblue tetrazolium was inhibited by superoxide dismutase, indicating the participation of superoxide anion radical in the autoxidation. Hydrogen peroxide stimulated the autoxidation and superoxide dismutase inhibited the hydrogen peroxide-induced oxidation, results which suggest the participation of hydrogen peroxide in autoxidation and in the generation of superoxide radical. An assay for superoxide dismutase using autoxidation of hydroxylamine is described.
Topics: Hydrogen Peroxide; Hydroxylamine; Hydroxylamines; Nitroblue Tetrazolium; Oxidation-Reduction; Superoxide Dismutase; Superoxides
PubMed: 35667906
DOI: 10.1016/j.abb.2022.109247 -
Journal of Nanobiotechnology May 2024Various clinical symptoms of digestive system, such as infectious, inflammatory, and malignant disorders, have a profound impact on the quality of life and overall... (Review)
Review
Various clinical symptoms of digestive system, such as infectious, inflammatory, and malignant disorders, have a profound impact on the quality of life and overall health of patients. Therefore, the chase for more potent medicines is both highly significant and urgent. Nanozymes, a novel class of nanomaterials, amalgamate the biological properties of nanomaterials with the catalytic activity of enzymes, and have been engineered for various biomedical applications, including complex gastrointestinal diseases (GI). Particularly, because of their distinctive metal coordination structure and ability to maximize atom use efficiency, single-atom nanozymes (SAzymes) with atomically scattered metal centers are becoming a more viable substitute for natural enzymes. Traditional nanozyme design strategies are no longer able to meet the current requirements for efficient and diverse SAzymes design due to the diversification and complexity of preparation processes. As a result, this review emphasizes the design concept and the synthesis strategy of SAzymes, and corresponding bioenzyme-like activities, such as superoxide dismutase (SOD), peroxidase (POD), oxidase (OXD), catalase (CAT), and glutathione peroxidase (GPx). Then the various application of SAzymes in GI illnesses are summarized, which should encourage further research into nanozymes to achieve better application characteristics.
Topics: Humans; Gastrointestinal Diseases; Nanostructures; Animals; Enzymes; Superoxide Dismutase; Catalase; Catalysis; Glutathione Peroxidase
PubMed: 38796465
DOI: 10.1186/s12951-024-02569-3 -
Methods in Molecular Biology (Clifton,... 2022Localizing metal binding to specific sites in proteins remains a challenging analytical problem in vitro and in vivo. Although metal binding can be maintained by...
Localizing metal binding to specific sites in proteins remains a challenging analytical problem in vitro and in vivo. Although metal binding can be maintained by "native" electrospray ionization with intact proteins for quantitation by mass spectrometry, subsequent fragmentation of proteins with slow-heating methods like collision-induced dissociation (CID) can scramble and detach metals. In contrast, electron capture dissociation (ECD) fragmentation produces highly localized bond cleavage that is well known to preserve posttranslational modifications. We show how a newly available ECD tool that can be retrofitted on standard QTOF mass spectrometers allows the sites of copper and zinc binding to be localized in the antioxidant enzyme Cu, Zn superoxide dismutase (SOD1). The loss of zinc from Cu, Zn SOD1 has been shown to induce motor neuron death and could have a causal role in the fatal neurodegenerative disease, amyotrophic lateral sclerosis (ALS). The methods described enable copper loss to be distinguished from zinc using distinct ECD fragments of SOD1 and are broadly applicable to other metalloproteins.
Topics: Amyotrophic Lateral Sclerosis; Copper; Electrons; Humans; Mutation; Neurodegenerative Diseases; Superoxide Dismutase; Superoxide Dismutase-1; Zinc
PubMed: 35657595
DOI: 10.1007/978-1-0716-2325-1_14 -
ACS Applied Materials & Interfaces Sep 2020Cerium oxide nanoparticles have been shown to mimic oxidoreductase enzymes by catalyzing the decomposition of organic substrates and reactive oxygen species. This...
Cerium oxide nanoparticles have been shown to mimic oxidoreductase enzymes by catalyzing the decomposition of organic substrates and reactive oxygen species. This mimicry can be found in superoxide radicals and hydrogen peroxides, which are harmful molecules produced in oxidative stress-associated diseases. Despite the fact that nanoparticle functionalization is mandatory in the context of nanomedicine, the influence of polymer coatings on their enzyme-like catalytic activity is poorly understood. In this work, six polymer-coated cerium oxide nanoparticles are prepared by the association of 7.8 nm cerium oxide cores with two poly(sodium acrylate) and four poly(ethylene glycol) (PEG)-grafted copolymers with different terminal or anchoring end groups, such as phosphonic acids. The superoxide dismutase-, catalase-, peroxidase-, and oxidase-like catalytic activities of the coated nanoparticles were systematically studied. It is shown that the polymer coatings do not affect the superoxide dismutase-like, impair the catalase-like and oxidase-like, and surprisingly improves peroxidase-like catalytic activities of cerium oxide nanoparticles. It is also demonstrated that the particles coated with the PEG-grafted copolymers perform better than the poly(acrylic acid)-coated ones as oxidoreductase-like enzymes, a result that confirms the benefit of having phosphonic acids as anchoring groups at the particle surface.
Topics: Acrylic Resins; Catalase; Catalysis; Cerium; Nanoparticles; Oxidoreductases; Particle Size; Peroxidase; Polyethylene Glycols; Reactive Oxygen Species; Superoxide Dismutase; Surface Properties
PubMed: 32812730
DOI: 10.1021/acsami.0c08778 -
Animal Reproduction Science Nov 2019During cold storage stallion spermatozoa experience undergo oxidative stress, which can impair sperm function and fertilizing capacity. Superoxide dismutase (SOD),...
During cold storage stallion spermatozoa experience undergo oxidative stress, which can impair sperm function and fertilizing capacity. Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) are the main endogenous enzymatic antioxidants in stallion seminal plasma, and counteract reactive oxygen species. Semen dilution reduces the endogenous antioxidant concentrations. The aim of this study was to investigate whether addition of 15 IU/mL each of SOD, CAT, and GPX to diluted stallion semen would ameliorate a reactive oxygen-mediated decrease in semen quality during 72 h of storage at 5 °C. Ejaculates (n = 7) were divided in two aliquots and diluted in INRA 96 without (control) or with addition of antioxidants. Semen analysis was performed at the time of dilution and every 24 h during chilled storage. Antioxidant supplementation completely inhibited the storage-dependent increase in activated caspase 3 (P < 0.05). Concomitantly, the antioxidant-supplemented samples had a greater percentage of viable, motile and rapidly moving sperm than control samples after 72 h storage (P < 0.05). The DNA damage, as evaluated by TUNEL assay and SCSA, increased with storage time (P < 0.05). Antioxidant supplementation did not prevent, but did significantly reduce the increase in DNA strand breakage. The results indicate part of the intrinsic apoptotic pathway leading to effector caspase activation was inhibited, although an activation of molecules with endonuclease activity still occurred. In conclusion, adding equal concentrations of SOD, CAT and GPX to a semen extender suppressed caspase-3 activation and improved preservation of stallion sperm motility and viability during 72 h of storage at 5 °C.
Topics: Animals; Catalase; Glutathione Peroxidase; Horses; Male; Semen; Semen Analysis; Semen Preservation; Sperm Motility; Spermatozoa; Superoxide Dismutase
PubMed: 31635777
DOI: 10.1016/j.anireprosci.2019.106195 -
Biochemical and Biophysical Research... Oct 2019Metal ion coordination is an essential step for the maturation of metalloenzymes. Generally, the metal coordination sites are thought to be fully occupied to achieve the...
Metal ion coordination is an essential step for the maturation of metalloenzymes. Generally, the metal coordination sites are thought to be fully occupied to achieve the maximum activity and stability. In this research, we compared the structural features, activity and stability of the apo-, semiholo- and holo-forms of a hyperthermostable tetrameric Fe-superoxide dismutase (SOD). Strikingly, the three forms of enzymes had similar compact tetrameric structures. Removal of iron ions destabilized subunit-subunit interactions during guanidine hydrochloride-induced unfolding. The partially metalized semiholoenzyme possessed most of the activity and identical hyperthermostability of the holoenzyme, but weaker propensity to aggregate. Furthermore, both of the iron content and activity of the semiholoenzyme were unaffected by a 200-fold excess iron ions in solutions, suggesting that conformation of the apo-subunits were forced to the close state by the iron-containing subunits. These observations suggest that fully metalized enzyme is probably nonessential for multimeric metalloenzymes and the semiholoenzyme may be a better choice. The unique properties of semiholoenzyme also provide the organisms a compromised solution to survival under metal deficiency conditions.
Topics: Enzyme Stability; Humans; Models, Molecular; Mutagenesis, Site-Directed; Superoxide Dismutase; Temperature
PubMed: 31477266
DOI: 10.1016/j.bbrc.2019.08.135 -
Pesticide Biochemistry and Physiology Sep 2023Accumulating evidence suggests that superoxide dismutase (SOD) is the first line of antioxidant defense in organisms and plays an important role in scavenging reactive...
Accumulating evidence suggests that superoxide dismutase (SOD) is the first line of antioxidant defense in organisms and plays an important role in scavenging reactive oxygen species produced during environmental stress. However, limited information is available regarding the response of SOD genes to cold stress in ticks. Therefore, in the present study, SOD genes were cloned and identified from the genome of Haemaphysalis longicornis, and the function of SOD during the cold response was further explored. Seven SOD genes were characterized: HlCCS1, HlCCS2, HlMSD, HlCSD1, HlCSD2, HlCSD3, and HlCSD4. Bioinformatics analysis showed that HlCCS1 and HlCCS2 are copper chaperones of SODs. HlCSD1-HlCSD4 belong to the Cu/Zn SOD, whereas HlMSD belongs to the Mn SOD gene family. Fluorescence quantitative PCR showed that the expression of HlCCS2, HlMSD, and HlCSD1-3 was upregulated, whereas HlCCS1 and HlCSD4 were downregulated during the cold response of H. longicornis. Western blotting confirmed changes in the relative expression of HlCSD3 and HlMSD in H. longicornis after cold treatment. Mortality of H. longicornis increased significantly after dsRNA injection of HlCCS2, HlMSD, HlCSD1, and HlCSD3. The above results show that SODs have different regulatory functions during the cold response in H. longicornis, and there might be an interaction between treatment temperature and duration. Furthermore, the results lay a foundation for subsequent research on the molecular mechanism of cold tolerance in H. longicornis and shed light on the population distribution and diffusion limit of ticks.
Topics: Animals; Ticks; Superoxide Dismutase; Cold Temperature; Temperature; Copper
PubMed: 37666626
DOI: 10.1016/j.pestbp.2023.105573 -
PloS One 2021Oxidative stress, which could be evoked by numerous inducements including mycotoxins like deoxynivalenol (DON), cause severe damages to organisms. Antioxidants are...
Oxidative stress, which could be evoked by numerous inducements including mycotoxins like deoxynivalenol (DON), cause severe damages to organisms. Antioxidants are promising protectants against oxidative stress that could be applied in pharmaceutical, cosmetic, and food and feed industries. In this study, a thermostable and acidophilic superoxide dismutase (AaSOD) was used to develop an antioxidant product that can potentially protect organisms from oxidative stress related damages. The enzyme was successfully expressed as an extracelluar protein in Bacillus subtilis with a high yield. To obtain a feasible protocol for industrial production of AaSOD, the fermentation mediums that are commonly used for culturing B. subtilis were screened, the feasibility of expressing AaSOD without antibiotic as selection pressure was confirmed, and the effect of using lactose as an inducer instead of isopropyl-β-d-thiogalactoside (IPTG) was investigated. Batch fermentation was conducted to validate the optimized conditions for AaSOD production, and 6530 U mL-1 of SOD activity was obtained in the fermentation broth. The dry powder product of AaSOD with an activity of 22202 U g-1 was prepared by spray-drying and was administrated on zebrafish to test its function as a protectant against DON, and thus gained a significant redress of the reactive oxygen species (ROS) accumulation induced by DON. Taken together, this study provides a feasible protocol to prepare the AaSOD-based antioxidant product that is potentially applied in livestock industry.
Topics: Animals; Bacillus subtilis; Bacterial Proteins; Batch Cell Culture Techniques; Cloning, Molecular; Culture Media; Enzyme Stability; Fermentation; Mycotoxins; Oxidative Stress; Protein Engineering; Reactive Oxygen Species; Superoxide Dismutase; Thermodynamics; Zebrafish
PubMed: 34784394
DOI: 10.1371/journal.pone.0260047 -
The Aging Male : the Official Journal... Dec 2020We have aimed to determine whether oxidants-antioxidants play a role in the etiopathogenesis of bladder tumour by measuring their levels in the serums of patients with...
PURPOSE
We have aimed to determine whether oxidants-antioxidants play a role in the etiopathogenesis of bladder tumour by measuring their levels in the serums of patients with bladder tumour.
MATERIAL METHOD
Thirty patients with bladder tumour with superficial bladder tumour and 27 normal healthy volunteers were included in the study. Four cc of venous blood was taken from these patients and volunteers in the control group and centrifuged at 5000 rpm for 10 minutes and divided into serum and plasma. The activities of xanthine oxidase, glutathione reductase, glutathione-s transferase, reduced glutathione and superoxide dismutase enzymes in serum were then measured spectrophotometrically.
FINDINGS
Antioxidant parameters (glutathione-s-transferase, reduced glutathione, superoxide dismutase and glutathione reductase) in the serum of patients with bladder tumours were found statistically significantly lower than control group ( < .05). On the other hand, xanthine oxidase which is an oxidant indicator, was found significantly higher in patients with bladder cancer than control group ( < .05).
CONCLUSION
Oxidative stress is effective in the etiopathogenesis of bladder tumour. We, therefore, believe that antioxidants are protective against bladder tumours and will be effective in the treatment of bladder tumours.
Topics: Antioxidants; Glutathione Reductase; Humans; Oxidants; Oxidative Stress; Superoxide Dismutase; Urinary Bladder Neoplasms
PubMed: 32020825
DOI: 10.1080/13685538.2020.1718636 -
Developmental and Comparative Immunology Feb 2022Superoxide dismutases (SODs) are metalloenzymes that convert superoxide radicals to HO and O. Although SODs have been extensively studied in mammals and other species,...
Superoxide dismutases (SODs) are metalloenzymes that convert superoxide radicals to HO and O. Although SODs have been extensively studied in mammals and other species, comparative studies in invertebrates, such as abalones, are lacking. Here, we aimed to characterize manganese superoxide dismutase in disk abalone (Haliotis discus discus) (AbMnSOD) by assessing its transcriptional levels at different embryonic developmental stages. Additionally, the temporal expression of AbMnSOD in different abalone tissues in response to bacterial, viral, and pathogen-associated molecular pattern (PAMP) stimuli was investigated. SOD activity was measured at various recombinant protein concentrations via the xanthine oxidase/WST-1 system. Cell viability upon exposure to HO, wound healing ability, and subcellular localization were determined in AbMnSOD-transfected cells. AbMnSOD was 681 bp long and contained the SOD-A domain. AbMnSOD expression was higher at the trochophore stage than at the other stages. When challenged with immune stimulants, AbMnSOD showed the highest expression at 6 h post-injection (p.i.) for all stimulants except lipopolysaccharides. In the gills, the highest AbMnSOD expression was observed at 6 h p.i., except for the Vibrio parahaemolyticus challenge. Recombinant AbMnSOD showed concentration-dependent xanthine oxidase activity. Furthermore, AbMnSOD-transfected cells survived HO-induced apoptosis and exhibited significant wound gap closure. As expected, AbMnSOD was localized in the mitochondria of the cells. Our findings suggest that AbMnSOD is an essential antioxidant enzyme that participates in regulating developmental processes and defense mechanisms against oxidative stress in hosts.
Topics: Animals; Gastropoda; Gene Expression Regulation; Hydrogen Peroxide; Immunity, Innate; Mammals; Phylogeny; Superoxide Dismutase; Vibrio parahaemolyticus
PubMed: 34662686
DOI: 10.1016/j.dci.2021.104299