Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
10.6
6.0
Journals
Antioxidants
Special Issues
A Lesson from Microorganisms: How to Counteract Oxidative Stress
share announcement

A Lesson from Microorganisms: How to Counteract Oxidative Stress

A special issue of Antioxidants (ISSN 2076-3921).

Deadline for manuscript submissions: closed (15 October 2023) | Viewed by 18922

Special Issue Editors

Dr. Danila Limauro

E-Mail Website
Guest Editor
Department of Biology, University of Naples Federico II, Naples, Italy
Interests: antioxidants; oxidative stress; thermophiles; redox homeostasis; protein disulfide oxidoreductase; xenobiotics; glycosyl hydrolase; cellulase; hemicellulase
Dr. Emilia Pedone

E-Mail
Co-Guest Editor
Biostructures and Bioimaging of C.N.R, V. Mezzocannone 16, 80134 Naples, Italy
Interests: protein–protein interactions; protein structure-function relationship; cell-macromolecules interactions; biophysical characterization; thermophilic microorganisms; protein disulfide oxidoreductase
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Antioxidant systems exist in cells to protect them against reactive oxygen species (ROS) that damage major biomolecules. Microorganisms to fight ROS are equipped with powerful enzymatic (e.g., superoxide dismutase (SOD), catalase, and peroxidase) and non-enzymatic (e.g., glutathione) antioxidants to prevent oxidative damage to cells. The microbial world offers great antioxidant potential because of the enormous diversity of microorganisms that colonize different environments ranging from humans to extreme ecological niches. In addition, microbes offer a source of interest for innovative biotechnologies in this field.

This Special Issue focuses on the molecular strategies adopted by microorganisms to combat oxidative stress and the possible biotechnological application. All researchers working in the field are cordially invited to contribute original research articles or reviews to this Special Issue.

Dr. Danila Limauro
Guest Editor
Dr. Emilia Pedone
Co-Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Antioxidants is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2900 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Microorganisms
  • Extremophiles 
  • Reactive oxygen species (ROS) 
  • Antioxidants 
  • Oxidative stress 
  • Redox homeostasis 
  • DNA damage 
  • Protein oxidation 
  • Stress response 
  • Heavy metals

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Published Papers (7 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

19 pages, 1808 KiB  
Article
Antioxidant Capacity of Carotenoid Extracts from the Haloarchaeon Halorhabdus utahensis
by Ismene Serino, Giuseppe Squillaci, Sara Errichiello, Virginia Carbone, Lidia Baraldi, Francesco La Cara and Alessandra Morana
Antioxidants 2023, 12(10), 1840; https://doi.org/10.3390/antiox12101840 - 10 Oct 2023
Cited by 10 | Viewed by 1878
Abstract
Herein, we report on the production, characterization, and antioxidant power assessment of carotenoids from the haloarchaeon Halorhabdus utahensis. It was grown at 37 °C and 180 rpm agitation in halobacteria medium supplemented with glucose, fructose, and xylose, each at concentrations of 0.2%, [...] Read more.
Herein, we report on the production, characterization, and antioxidant power assessment of carotenoids from the haloarchaeon Halorhabdus utahensis. It was grown at 37 °C and 180 rpm agitation in halobacteria medium supplemented with glucose, fructose, and xylose, each at concentrations of 0.2%, 1%, and 2%, and the carotenoid yield and composition were investigated. The microorganism produced the carotenoids under all the conditions tested, and their amount followed the order glucose < xylose < fructose. The highest yield was achieved in 2% fructose growth medium with 550.60 ± 7.91 μg/g dry cell and 2428.15 ± 49.33 μg/L. Separation and identification of the carotenoids were performed by RP-HPLC and HPLC/APCI-ITMSn. Bacterioruberin was the main carotenoid detected and accounted for 60.6%, 56.4%, and 58.9% in 2% glucose, 1% xylose, and 2% fructose extracts, respectively. Several geometric isomers of bacterioruberin were distinguished, and representatives of monoanhydrobacterioruberin, and bisanhydrobacterioruberin were also detected. The assignment to cis-isomers was attempted through analysis of the UV/Vis spectra, intensity of cis peaks, and spectral fine structures. The extracts exhibited superoxide scavenging activity higher than butylhydroxytoluene, ascorbic acid, and Trolox, selected as antioxidant references. The anti-hyaluronidase capacity was investigated, and the 2% fructose extract showed the highest activity reaching 90% enzyme inhibition with 1.5 μg. The overall data confirm that Hrd. utahensis can be regarded as an interesting source of antioxidants that can find applications in the food and cosmetic sectors. Full article
(This article belongs to the Special Issue A Lesson from Microorganisms: How to Counteract Oxidative Stress)
►▼ Show Figures

Figure 1

12 pages, 2852 KiB  
Article
Protein Kinase A Controls the Melanization of Candida auris through the Alteration of Cell Wall Components
by Ji-Seok Kim and Yong-Sun Bahn
Antioxidants 2023, 12(9), 1702; https://doi.org/10.3390/antiox12091702 - 31 Aug 2023
Cited by 1 | Viewed by 1610
Abstract
Candida auris, a multidrug-resistant fungal pathogen, significantly threatens global public health. Recent studies have identified melanin production, a key virulence factor in many pathogenic fungi that protects against external threats like reactive oxygen species, in C. auris. However, the melanin regulation [...] Read more.
Candida auris, a multidrug-resistant fungal pathogen, significantly threatens global public health. Recent studies have identified melanin production, a key virulence factor in many pathogenic fungi that protects against external threats like reactive oxygen species, in C. auris. However, the melanin regulation mechanism remains elusive. This study explores the role of the Ras/cAMP/PKA signaling pathway in C. auris melanization. It reveals that the catalytic subunits Tpk1 and Tpk2 of protein kinase A (PKA) are essential, whereas Ras1, Gpr1, Gpa2, and Cyr1 are not. Under melanin-promoting conditions, the tpk1Δ tpk2Δ strain formed melanin granules in the supernatant akin to the wild-type strain but failed to adhere them properly to the cell wall. This discrepancy is likely due to a decreased expression of chitin-synthesis-related genes. Our findings also show that Tpk1 primarily drives melanization, with Tpk2 having a lesser impact. To corroborate this, we found that C. auris must deploy Tpk1-dependent melanin deposition as a defensive mechanism against antioxidant exposure. Moreover, we confirmed that deletion mutants of multicopper oxidase and ferroxidase genes, previously assumed to influence C. auris melanization, do not directly contribute to the process. Overall, this study sheds light on the role of PKA in C. auris melanization and enhances our understanding of the pathogenicity mechanisms of this emerging fungal pathogen. Full article
(This article belongs to the Special Issue A Lesson from Microorganisms: How to Counteract Oxidative Stress)
►▼ Show Figures

Figure 1

19 pages, 5155 KiB  
Article
Insights into the Lysine Acetylome of the Haloarchaeon Haloferax volcanii during Oxidative Stress by Quantitative SILAC-Based Proteomics
by Ricardo L. Couto-Rodríguez, Jin Koh, Sixue Chen and Julie A. Maupin-Furlow
Antioxidants 2023, 12(6), 1203; https://doi.org/10.3390/antiox12061203 - 1 Jun 2023
Cited by 3 | Viewed by 2121
Abstract
Oxidative stress adaptation strategies are important to cell function and are linked to cardiac, neurodegenerative disease, and cancer. Representatives of the Archaea domain are used as model organisms based on their extreme tolerance to oxidants and close evolutionary relationship with eukaryotes. A study [...] Read more.
Oxidative stress adaptation strategies are important to cell function and are linked to cardiac, neurodegenerative disease, and cancer. Representatives of the Archaea domain are used as model organisms based on their extreme tolerance to oxidants and close evolutionary relationship with eukaryotes. A study of the halophilic archaeon Haloferax volcanii reveals lysine acetylation to be associated with oxidative stress responses. The strong oxidant hypochlorite: (i) stimulates an increase in lysine acetyltransferase HvPat2 to HvPat1 abundance ratios and (ii) selects for lysine deacetylase sir2 mutants. Here we report the dynamic occupancy of the lysine acetylome of glycerol-grown H. volcanii as it shifts in profile in response to hypochlorite. These findings are revealed by the: (1) quantitative multiplex proteomics of the SILAC-compatible parent and Δsir2 mutant strains and (2) label-free proteomics of H26 ‘wild type’ cells. The results show that lysine acetylation is associated with key biological processes including DNA topology, central metabolism, cobalamin biosynthesis, and translation. Lysine acetylation targets are found conserved across species. Moreover, lysine residues modified by acetylation and ubiquitin-like sampylation are identified suggesting post-translational modification (PTM) crosstalk. Overall, the results of this study expand the current knowledge of lysine acetylation in Archaea, with the long-term goal to provide a balanced evolutionary perspective of PTM systems in living organisms. Full article
(This article belongs to the Special Issue A Lesson from Microorganisms: How to Counteract Oxidative Stress)
►▼ Show Figures

Graphical abstract

19 pages, 2193 KiB  
Article
Transposon-Directed Insertion-Site Sequencing Reveals Glycolysis Gene gpmA as Part of the H2O2 Defense Mechanisms in Escherichia coli
by Myriam Roth, Emily C. A. Goodall, Karthik Pullela, Vincent Jaquet, Patrice François, Ian R. Henderson and Karl-Heinz Krause
Antioxidants 2022, 11(10), 2053; https://doi.org/10.3390/antiox11102053 - 18 Oct 2022
Cited by 5 | Viewed by 2502
Abstract
Hydrogen peroxide (H2O2) is a common effector of defense mechanisms against pathogenic infections. However, bacterial factors involved in H2O2 tolerance remain unclear. Here we used transposon-directed insertion-site sequencing (TraDIS), a technique allowing the screening of the [...] Read more.
Hydrogen peroxide (H2O2) is a common effector of defense mechanisms against pathogenic infections. However, bacterial factors involved in H2O2 tolerance remain unclear. Here we used transposon-directed insertion-site sequencing (TraDIS), a technique allowing the screening of the whole genome, to identify genes implicated in H2O2 tolerance in Escherichia coli. Our TraDIS analysis identified 10 mutants with fitness defect upon H2O2 exposure, among which previously H2O2-associated genes (oxyR, dps, dksA, rpoS, hfq and polA) and other genes with no known association with H2O2 tolerance in E. coli (corA, rbsR, nhaA and gpmA). This is the first description of the impact of gpmA, a gene involved in glycolysis, on the susceptibility of E. coli to H2O2. Indeed, confirmatory experiments showed that the deletion of gpmA led to a specific hypersensitivity to H2O2 comparable to the deletion of the major H2O2 scavenger gene katG. This hypersensitivity was not due to an alteration of catalase function and was independent of the carbon source or the presence of oxygen. Transcription of gpmA was upregulated under H2O2 exposure, highlighting its role under oxidative stress. In summary, our TraDIS approach identified gpmA as a member of the oxidative stress defense mechanism in E. coli. Full article
(This article belongs to the Special Issue A Lesson from Microorganisms: How to Counteract Oxidative Stress)
►▼ Show Figures

Figure 1

20 pages, 4096 KiB  
Article
The Catalase KatA Contributes to Microaerophilic H2O2 Priming to Acquire an Improved Oxidative Stress Resistance in Staphylococcus aureus
by Nico Linzner, Vu Van Loi and Haike Antelmann
Antioxidants 2022, 11(9), 1793; https://doi.org/10.3390/antiox11091793 - 12 Sep 2022
Cited by 8 | Viewed by 2623
Abstract
Staphylococcus aureus has to cope with oxidative stress during infections. In this study, S. aureus was found to be resistant to 100 mM H2O2 during aerobic growth. While KatA was essential for this high aerobic H2O2 resistance, [...] Read more.
Staphylococcus aureus has to cope with oxidative stress during infections. In this study, S. aureus was found to be resistant to 100 mM H2O2 during aerobic growth. While KatA was essential for this high aerobic H2O2 resistance, the peroxiredoxin AhpC contributed to detoxification of 0.4 mM H2O2 in the absence of KatA. In addition, the peroxiredoxins AhpC, Tpx and Bcp were found to be required for detoxification of cumene hydroperoxide (CHP). The high H2O2 tolerance of aerobic S. aureus cells was associated with priming by endogenous H2O2 levels, which was supported by an oxidative shift of the bacillithiol redox potential to −291 mV compared to −310 mV in microaerophilic cells. In contrast, S. aureus could be primed by sub-lethal doses of 100 µM H2O2 during microaerophilic growth to acquire an improved resistance towards the otherwise lethal triggering stimulus of 10 mM H2O2. This microaerophilic priming was dependent on increased KatA activity, whereas aerobic cells showed constitutive high KatA activity. Thus, KatA contributes to the high H2O2 resistance of aerobic cells and to microaerophilic H2O2 priming in order to survive the subsequent lethal triggering doses of H2O2, allowing the adaptation of S. aureus under infections to different oxygen environments. Full article
(This article belongs to the Special Issue A Lesson from Microorganisms: How to Counteract Oxidative Stress)
►▼ Show Figures

Figure 1

30 pages, 7838 KiB  
Article
Endophytic Fungal Consortia Enhance Basal Drought-Tolerance in Moringa oleifera by Upregulating the Antioxidant Enzyme (APX) through Heat Shock Factors
by Javeria Javed, Mamoona Rauf, Muhammad Arif, Muhammad Hamayun, Humaira Gul, Aziz Ud-Din, Jalal Ud-Din, Mohammad Sohail, Muhammad Mizanur Rahman and In-Jung Lee
Antioxidants 2022, 11(9), 1669; https://doi.org/10.3390/antiox11091669 - 27 Aug 2022
Cited by 25 | Viewed by 3469
Abstract
Global climate change has imposed harsh environmental conditions such as drought. Naturally, the most compatible fungal consortia operate synergistically to enhance plant growth and ecophysiological responses against abiotic strains. Yet, little is known about the interactions between phytohormone-producing endophytic fungal symbionts and plant [...] Read more.
Global climate change has imposed harsh environmental conditions such as drought. Naturally, the most compatible fungal consortia operate synergistically to enhance plant growth and ecophysiological responses against abiotic strains. Yet, little is known about the interactions between phytohormone-producing endophytic fungal symbionts and plant growth under drought stress. The existing research was rationalized to recognize the role of newly isolated drought-resistant, antioxidant-rich endophytic fungal consortia hosting a xerophytic plant, Carthamus oxycantha L., inoculated to Moringa oleifera L. grown under drought stress of 8% PEG (polyethylene glycol-8000). Under drought stress, the combined inoculation of endophytic strain Microdochium majus (WA), Meyerozyma guilliermondi (TG), and Aspergillus aculeatus (TL3) exhibited a significant improvement in growth attributes such as shoot fresh weight (1.71-fold), shoot length (0.86-fold), root length (0.65-fold), dry weight (2.18-fold), total chlorophyll (0.46-fold), and carotenoids (0.87-fold) in comparison to control (8% PEG). Primary and secondary metabolites were also increased in M. oleifera inoculated with endophytic consortia, under drought stress, such as proteins (1.3-fold), sugars (0.58-fold), lipids (0.41-fold), phenols (0.36-fold), flavonoids (0.52-fold), proline (0.6-fold), indole acetic acid (IAA) (4.5-fold), gibberellic acid (GA) (0.7-fold), salicylic acid (SA) (0.8-fold), ascorbic acid (ASA) (1.85-fold), while abscisic acid (ABA) level was decreased (−0.61-fold) in comparison to the control (8% PEG). Under drought stress, combined inoculation (WA, TG, TL3) also promoted the antioxidant activities of enzymes such as ascorbate peroxidase (APX) (3.5-fold), catalase (CAT) activity (1.7-fold), and increased the total antioxidant capacity (TAC) (0.78-fold) with reduced reactive oxygen species (ROS) such as H2O2 production (−0.4-fold), compared to control (8% PEG), and stomatal aperture was larger (3.5-fold) with a lesser decrease (−0.02-fold) in water potential. Moreover, combined inoculation (WA, TG, TL3) up regulated the expression of MolHSF3, MolHSF19, and MolAPX genes in M. oleifera under drought stress, compared to the control (8% PEG), is suggestive of an important regulatory role for drought stress tolerance governed by fungal endophytes. The current research supports the exploitation of the compatible endophytic fungi for establishing the tripartite mutualistic symbiosis in M. oleifera to alleviate the adverse effects of drought stress through strong antioxidant activities. Full article
(This article belongs to the Special Issue A Lesson from Microorganisms: How to Counteract Oxidative Stress)
►▼ Show Figures

Graphical abstract

22 pages, 4965 KiB  
Article
Analysis of Carotenoids in Haloarchaea Species from Atacama Saline Lakes by High Resolution UHPLC-Q-Orbitrap-Mass Spectrometry: Antioxidant Potential and Biological Effect on Cell Viability
by Catherine Lizama, Javier Romero-Parra, Daniel Andrade, Felipe Riveros, Jorge Bórquez, Shakeel Ahmed, Luis Venegas-Salas, Carolina Cabalín and Mario J. Simirgiotis
Antioxidants 2021, 10(8), 1230; https://doi.org/10.3390/antiox10081230 - 30 Jul 2021
Cited by 26 | Viewed by 3446
Abstract
Haloarchaea are extreme halophilic microorganisms belonging to the domain Archaea, phylum Euryarchaeota, and are producers of interesting antioxidant carotenoid compounds. In this study, four new strains of Haloarcula sp., isolated from saline lakes of the Atacama Desert, are reported and studied by high-resolution [...] Read more.
Haloarchaea are extreme halophilic microorganisms belonging to the domain Archaea, phylum Euryarchaeota, and are producers of interesting antioxidant carotenoid compounds. In this study, four new strains of Haloarcula sp., isolated from saline lakes of the Atacama Desert, are reported and studied by high-resolution mass spectrometry (UHPLC-Q-Orbitrap-MS/MS) for the first time. In addition, determination of the carotenoid pigment profile from the new strains of Haloarcula sp., plus two strains of Halorubrum tebenquichense, and their antioxidant activity by means of several methods is reported. The effect of biomass on cellular viability in skin cell lines was also evaluated by MTT assay. The cholinesterase inhibition capacity of six haloarchaea (Haloarcula sp. ALT-23; Haloarcula sp. TeSe-41; Haloarcula sp. TeSe-51; Haloarcula sp. Te Se-89 and Halorubrum tebenquichense strains TeSe-85 and Te Se-86) is also reported for the first time. AChE inhibition IC50 was 2.96 ± 0.08 μg/mL and BuChE inhibition IC50 was 2.39 ± 0.09 μg/mL for the most active strain, Halorubrum tebenquichense Te Se-85, respectively, which is more active in BuCHe than that of the standard galantamine. Docking calculation showed that carotenoids can exert their inhibitory activity fitting into the enzyme pocket by their halves, in the presence of cholinesterase dimers. Full article
(This article belongs to the Special Issue A Lesson from Microorganisms: How to Counteract Oxidative Stress)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-7
Back to TopTop