Peroxin FgPEX22-Like Is Involved in FgPEX4 Tethering and Fusarium graminearum Pathogenicity

Peroxisomes are essential organelles that play important roles in a variety of biological processes in eukaryotic cells. To understand the synthesis of peroxisomes comprehensively, we identified the gene FgPEX22-like, encoding FgPEX22-like, a peroxin, in Fusarium graminearum. Our results showed that although FgPEX22-like was notably different from other peroxins (PEX) in Saccharomyces cerevisiae, it contained a predicted PEX4-binding site and interacted with FgPEX4 as a rivet protein of FgPEX4. To functionally characterize the roles of FgPEX22-like in F. graminearum, we performed homologous recombination to construct a deletion mutant (ΔPEX22-like). Analysis of the mutant showed that FgPEX22-like was essential for sexual and asexual reproduction, fatty acid utilization, pathogenicity, and production of the mycotoxin deoxynivalenol. Deletion of FgPEX22-like also led to increased production of lipid droplets and decreased elimination of reactive oxygen species. In addition, FgPEX22-like was required for the biogenesis of Woronin bodies. Taken together, our data demonstrate that FgPEX22-like is a peroxin in F. graminearum that interacts with PEX4 by anchoring PEX4 at the peroxisomal membrane and contributes to the peroxisome function in F. graminearum.

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Effects of Ubiquinol-10 on MicroRNA-146a Expression In Vitro and In Vivo

Mediators of Inflammation ◽

10.1155/2009/415437 ◽

2009 ◽

Vol 2009 ◽

pp. 1-7 ◽

Cited By ~ 24

Author(s):

Constance Schmelzer ◽

Mitsuaki Kitano ◽

Gerald Rimbach ◽

Petra Niklowitz ◽

Thomas Menke ◽

...

Keyword(s):

Gene Expression ◽

Reactive Oxygen Species ◽

Biological Processes ◽

Oxygen Species ◽

Moderate Reduction ◽

Suppression Of Gene Expression ◽

Fine Tune ◽

Dependent Pathway

MicroRNAs (miRs) are involved in key biological processes via suppression of gene expression at posttranscriptional levels. According to their superior functions, subtle modulation of miR expression by certain compounds or nutrients is desirable under particular conditions. Bacterial lipopolysaccharide (LPS) induces a reactive oxygen species-/NF-κB-dependent pathway which increases the expression of the anti-inflammatory miR-146a. We hypothesized that this induction could be modulated by the antioxidant ubiquinol-10. Preincubation of human monocytic THP-1 cells with ubiquinol-10 reduced the LPS-induced expression level of miR-146a to 78.9±13.22%. In liver samples of mice injected with LPS, supplementation with ubiquinol-10 leads to a reduction of LPS-induced miR-146a expression to 78.12±21.25%. From these consistent in vitro and in vivo data, we conclude that ubiquinol-10 may fine-tune the inflammatory response via moderate reduction of miR-146a expression.

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Lipid droplets alleviate cadmium induced cytotoxicity in Saccharomyces cerevisiae

Toxicology Research ◽

10.1039/c6tx00187d ◽

2017 ◽

Vol 6 (1) ◽

pp. 30-41 ◽

Cited By ~ 5

Author(s):

Selvaraj Rajakumar ◽

Vasanthi Nachiappan

Keyword(s):

Oxidative Stress ◽

Saccharomyces Cerevisiae ◽

Reactive Oxygen Species ◽

Lipid Accumulation ◽

Lipid Droplets ◽

Reactive Oxygen ◽

Oxygen Species

Cadmium (Cd) induces oxidative stress that generates reactive oxygen species (ROS) and increased lipid accumulation.

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Bacillomycin D Produced by Bacillus amyloliquefaciens Is Involved in the Antagonistic Interaction with the Plant-Pathogenic Fungus Fusarium graminearum

Applied and Environmental Microbiology ◽

10.1128/aem.01075-17 ◽

2017 ◽

Vol 83 (19) ◽

Cited By ~ 57

Author(s):

Qin Gu ◽

Yang Yang ◽

Qiming Yuan ◽

Guangming Shi ◽

Liming Wu ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Fusarium Graminearum ◽

Bacillus Amyloliquefaciens ◽

Morphological Changes ◽

Reactive Oxygen ◽

Oxygen Species ◽

Strong Activity ◽

Content Type ◽

Mitogen Activated Protein ◽

Bacillomycin D

ABSTRACT Fusarium graminearum (teleomorph: Ascomycota, Hypocreales, Gibberella, Gibberella zeae) is a destructive fungal pathogen that threatens the production and quality of wheat and barley worldwide. Controlling this toxin-producing pathogen is a significant challenge. In the present study, the commercially available strain Bacillus amyloliquefaciens (Bacteria, Firmicutes, Bacillales, Bacillus) FZB42 showed strong activity against F. graminearum. The lipopeptide bacillomycin D, produced by FZB42, was shown to contribute to the antifungal activity. Purified bacillomycin D showed strong activity against F. graminearum, and its 50% effective concentration was determined to be approximately 30 μg/ml. Analyses using scanning and transmission electron microscopy revealed that bacillomycin D caused morphological changes in the plasma membranes and cell walls of F. graminearum hyphae and conidia. Fluorescence microscopy combined with different dyes showed that bacillomycin D induced the accumulation of reactive oxygen species and caused cell death in F. graminearum hyphae and conidia. F. graminearum secondary metabolism also responded to bacillomycin D challenge, by increasing the production of deoxynivalenol. Biological control experiments demonstrated that bacillomycin D exerted good control of F. graminearum on corn silks, wheat seedlings, and wheat heads. In response to bacillomycin D, F. graminearum genes involved in scavenging reactive oxygen species were downregulated, whereas genes involved in the synthesis of deoxynivalenol were upregulated. Phosphorylation of MGV1 and HOG1, the mitogen-activated protein kinases of F. graminearum, was increased in response to bacillomycin D. Taken together, these findings reveal the mechanism of the antifungal action of bacillomycin D. IMPORTANCE Biological control of plant disease caused by Fusarium graminearum is desirable. Bacillus amyloliquefaciens FZB42 is a representative of the biocontrol bacterial strains. In this work, the lipopeptide bacillomycin D, produced by FZB42, showed strong fungicidal activity against F. graminearum. Bacillomycin D caused morphological changes in the plasma membrane and cell wall of F. graminearum, induced accumulation of reactive oxygen species, and ultimately caused cell death in F. graminearum. Interestingly, when F. graminearum was challenged with bacillomycin D, the deoxynivalenol production, gene expression, mitogen-activated protein kinase phosphorylation, and pathogenicity of F. graminearum were significantly altered. These findings clarified the mechanisms of the activity of bacillomycin D against F. graminearum and highlighted the potential of B. amyloliquefaciens FZB42 as a biocontrol agent against F. graminearum.

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Photodynamic Effects of Novel XF Porphyrin Derivatives on Prokaryotic and Eukaryotic Cells

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.49.4.1542-1552.2005 ◽

2005 ◽

Vol 49 (4) ◽

pp. 1542-1552 ◽

Cited By ~ 158

Author(s):

T. Maisch ◽

C. Bosl ◽

R.-M. Szeimies ◽

N. Lehn ◽

C. Abels

Keyword(s):

Reactive Oxygen Species ◽

Antibiotic Resistance ◽

Reactive Oxygen ◽

Human Keratinocytes ◽

Eukaryotic Cells ◽

Resistance Pattern ◽

Resistant Bacteria ◽

Oxygen Species ◽

Gram Positive ◽

Methicillin Resistant

ABSTRACT The worldwide rise in the rates of antibiotic resistance of bacteria underlines the need for alternative antibacterial agents. A promising approach to the killing of gram-positive antibiotic-resistant bacteria of the skin uses light in combination with a photosensitizer to induce a phototoxic reaction. Different concentrations (0 to 100 μM) of porphyrin-based photosensitizers (CTP1, XF70, and XF73) and different incubation times (5 min, 1 h, and 4 h) were used to determine phototoxicity against two methicillin-resistant Staphylococcus aureus strains, one methicillin-sensitive S. aureus strain, one methicillin-resistant Staphylococcus epidermidis strain, one Escherichia coli strain, and human keratinocytes and fibroblasts. Incubation with 0.005 μM XF70 or XF73, followed by illumination, yielded a 3-log10 (≥99.9%) decrease in the viable cell numbers of all staphylococcal strains, indicating that the XF drugs have high degrees of potency against gram-positive bacteria and also that the activities of these novel drugs are independent of the antibiotic resistance pattern of the staphylococci examined. CTP1 was less potent against the staphylococci under the same conditions. At 0.005 μM, XF70 and XF73 demonstrated no toxicity toward fibroblasts or keratinocytes. No inactivation of E. coli was detected at this concentration. XF73 was confirmed to act via a reactive oxygen species from the results of studies with sodium azide (a quencher of singlet oxygen), which reduced the killing of both eukaryotic and prokaryotic cells. When a quencher of superoxide anion and the hydroxyl radical was used, cell killing was not inhibited. These results demonstrate that the porphyrin-based photosensitizers had concentration-dependent differences in their efficacies of killing of methicillin-resistant staphylococcal strains via reactive oxygen species without harming eukaryotic cells at the same concentrations.

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Metabolic Reprogramming and Reactive Oxygen Species in T Cell Immunity

Frontiers in Immunology ◽

10.3389/fimmu.2021.652687 ◽

2021 ◽

Vol 12 ◽

Author(s):

Hao-Yun Peng ◽

Jason Lucavs ◽

Darby Ballard ◽

Jugal Kishore Das ◽

Anil Kumar ◽

...

Keyword(s):

Reactive Oxygen Species ◽

T Cell ◽

Reactive Oxygen ◽

T Cell Immunity ◽

Metabolic Reprogramming ◽

T Cell Subsets ◽

Ros Generation ◽

Biological Processes ◽

Oxygen Species ◽

Cell Immunity

T cells undergo metabolic reprogramming and multiple biological processes to satisfy their energetic and biosynthetic demands throughout their lifespan. Several of these metabolic pathways result in the generation of reactive oxygen species (ROS). The imbalance between ROS generation and scavenging could result in severe damage to the cells and potential cell death, ultimately leading to T cell-related diseases. Interestingly, ROS play an essential role in T cell immunity. Here, we introduce the important connectivity between T cell lifespan and the metabolic reprogramming among distinct T cell subsets. We also discuss the generation and sources of ROS production within T cell immunity as well as highlight recent research concerning the effects of ROS on T cell activities.

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N-Acetyl Cysteine Abrogates Silver-Induced Reactive Oxygen Species in Human Cells Without Altering Silver-based Antimicrobial Activity

10.1101/792150 ◽

2019 ◽

Author(s):

Kush N. Shah ◽

Parth N. Shah ◽

Andrew R. Mullen ◽

Qingquan Chen ◽

Ralph J. DeBerardinis ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Antimicrobial Activity ◽

Citric Acid Cycle ◽

Eukaryotic Cells ◽

Ros Generation ◽

Oxygen Species ◽

Bronchial Epithelial ◽

Acid Cycle ◽

Silver Toxicity ◽

Lung Infections

AbstractSilver-based antimicrobials are widely used topically to treat infections associated with multi-drug resistant (MDR) pathogens. Expanding this topical use to aerosols to treat lung infections requires understanding and preventing silver toxicity in the respiratory tract. A key mechanism resulting in silver-induced toxicity is the production of reactive oxygen species (ROS). In this study, we have verified ROS generation in silver-treated bronchial epithelial (16HBE) cells prompting evaluation of three antioxidants, N-acetyl cysteine (NAC), ascorbic acid, and melatonin, to identify potential prophylactic agents. Among them, NAC was the only candidate that abrogated the ROS generation in response to silver exposure resulting in the rescue of these cells from silver-associated toxicity. Further, this protective effect directly translated to restoration of metabolic activity, as demonstrated by the normal levels of citric acid cycle metabolites in NAC-pretreated silver-exposed cells. As a result of the normalized citric acid cycle, cells pre-incubated with NAC demonstrated significantly higher levels of adenosine triphosphate (ATP) levels compared with NAC-free controls. Moreover, we found that this prodigious capacity of NAC to rescue silver-exposed cells was due not only to its antioxidant activity, but also to its ability to directly bind silver. Despite binding to silver, NAC did not alter the antimicrobial activity of silver.ImportanceAlthough silver is a potent, broad-spectrum antibiotic, silver-induced toxicity, primarily due to generation of ROS, remains a concern limiting its use beyond treatment of wounds. NAC has been widely used as an antioxidant to rescue eukaryotic cells from metal-associated toxicity. Thus, we have evaluated the capacity of NAC to abrogate silver toxicity in a human bronchial epithelial cell line (16HBE) as a step towards expanding the use of silver-based antimicrobials to treat lung infections. We found that NAC pre-incubation resurrects a healthy metabolic state in bronchial epithelial cells exposed to silver ions via a combination of its antioxidant and metal-binding properties. Finally, this ability of NAC to rescue silver-exposed eukaryotic cells does not alter the antimicrobial activity of silver. Thus, a silver-NAC combination holds tremendous potential as a future, non-toxic antimicrobial agent.

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The Redox Potential of a Heme Cofactor in Nitrosomonas europaea Cytochrome c Peroxidase: A Polarizable QM/MM Study

Physical Chemistry Chemical Physics ◽

10.1039/d0cp06632j ◽

2021 ◽

Author(s):

Elizabeth Anotonovna Karnaukh ◽

Ksenia B Bravaya

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Cytochrome C ◽

Redox Potential ◽

Redox Reactions ◽

Cytochrome C Peroxidase ◽

Biological Processes ◽

Oxygen Species ◽

Heme Cofactor ◽

Excess Reactive Oxygen Species

Redox reactions are crucial to biological processes that protect organisms against oxidative stress. Metalloenzymes, such as peroxidases which reduce excess reactive oxygen species into water, play a key role in...

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Reactive Oxygen Species in Vascular Formation and Development

Oxidative Medicine and Cellular Longevity ◽

10.1155/2013/374963 ◽

2013 ◽

Vol 2013 ◽

pp. 1-14 ◽

Cited By ~ 39

Author(s):

Yijiang Zhou ◽

Hui Yan ◽

Meiqun Guo ◽

Jianhua Zhu ◽

Qingzhong Xiao ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Reactive Oxygen ◽

G Protein Coupled Receptors ◽

Biological Processes ◽

Oxygen Species ◽

Muscle Cell Differentiation ◽

Smooth Muscle Cell Differentiation ◽

G Protein Coupled ◽

Signaling Components ◽

Vascular Formation

Reactive oxygen species (ROS) are derived from the metabolism of oxygen and are traditionally viewed as toxic byproducts that cause damage to biomolecules. It is now becoming widely acknowledged that ROS are key modulators in a variety of biological processes and pathological states. ROS mediate key signaling transduction pathways by reversible oxidation of certain signaling components and are involved in the signaling of growth factors, G-protein-coupled receptors, Notch, and Wnt and its downstream cascades including MAPK, JAK-STAT, NF-κB, and PI3K/AKT. Vascular formation and development is one of the most important events during embryogenesis and is vital for postnasal tissue repair. In this paper, we will discuss how ROS regulate different steps in vascular development, including smooth muscle cell differentiation, angiogenesis, endothelial progenitor cells recruitment, and vascular cell migration.

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Reactive Oxygen Species Induces Lipid Droplet Accumulation in HepG2 Cells by Increasing Perilipin 2 Expression

International Journal of Molecular Sciences ◽

10.3390/ijms19113445 ◽

2018 ◽

Vol 19 (11) ◽

pp. 3445 ◽

Cited By ~ 19

Author(s):

Yi Jin ◽

Yanjie Tan ◽

Lupeng Chen ◽

Yan Liu ◽

Zhuqing Ren

Keyword(s):

Reactive Oxygen Species ◽

Hydrogen Peroxide ◽

Liver Disease ◽

Lipid Droplet ◽

Lipid Accumulation ◽

Hepg2 Cells ◽

Lipid Droplets ◽

Reactive Oxygen ◽

Oxygen Species ◽

Lipid Droplet Formation

Non-alcoholic fatty liver disease (NAFLD) has become the world’s most common liver disease. The disease can develop liver fibrosis or even carcinomas from the initial hepatic steatosis, and this process is influenced by many factors. Reactive oxygen species (ROS), as potent oxidants in cells, have been reported previously to play an important role in the development of NAFLD progression via promoting neutral lipid accumulation. Here, we found that ROS can promote lipid droplet formation in hepatocytes by promoting perilipin2 (PLIN2) expression. First, we used different concentrations of hydrogen peroxide to treat HepG2 cells and found that the number of lipid droplets in the cells increased, however also that this effect was dose-independent. Then, the mRNA level of several lipid droplet-associated genes was detected with hydrogen peroxide treatment and the expression of PLIN2, PLIN5, and FSP27 genes was significantly up-regulated (p < 0.05). We overexpressed PLIN2 in HepG2 cells and found that the lipid droplets in the cells were markedly increased. Interference with PLIN2 inhibits ROS-induced lipid droplet formation, revealing that PLIN2 is a critical factor in this process. We subsequently analyzed the regulatory pathway and protein interaction network that is involved in PLIN2 and found that PLIN2 can regulate intracellular lipid metabolism through the PPARα/RXRA and CREB/CREBBP signaling pathways. The majority of the data indicated the correlation between hydrogen peroxide-induced PLIN2 and lipid droplet upregulation. In conclusion, ROS up-regulates the expression of PLIN2 in hepatocytes, whereas PLIN2 promotes the formation of lipid droplets resulting in lipid accumulation in liver tissues.

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