scholarly journals Proteomics Reveals Octyl Gallate as an Environmentally Friendly Wood Preservative Leading to Reactive Oxygen Species-Driven Metabolic Inflexibility and Growth Inhibition in White-Rot Fungi (Lenzites betulina and Trametes versicolor)

2021 ◽  
Vol 7 (2) ◽  
pp. 145
Author(s):  
Jin-Wei Xu ◽  
Chen-Chung Liao ◽  
Ke-Chang Hung ◽  
Zhong-Yao Wang ◽  
Yu-Tang Tung ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Antifungal Activity ◽  
Trametes Versicolor ◽  
Reactive Oxygen ◽  
White Rot Fungi ◽  
Environmentally Friendly ◽  
White Rot ◽  
Oxygen Species ◽  
Wood Preservatives ◽  
Lenzites Betulina

The most commonly applied wood preservatives are based on creosote, pentachlorophenol, and waterborne chromate copper arsenate, which negatively affect the environment. Thus, environmentally friendly wood preservatives are required. This study investigated the antifungal activity and mechanism of several long-chain alkyl gallates (3,4,5-trihydroxybenzoates) against white-rot fungi, Lenzites betulina and Trametes versicolor. The results revealed that octyl gallate (OG) had the best antifungal activity. Additionally, OG may have a mechanism of action similar to surfactants and inhibit ATPase activity, causing mitochondrial dysfunction and endogenous reactive oxygen species (ROS) production. Upon exposure to endogenous ROS, cells rapidly inhibit the synthesis of 60S ribosomal subunits, thus reducing the mycelial growth rate. L. betulina and T. versicolor also remodeled their energy metabolism in response to low ATP levels and endogenous ROS. After OG treatment, ATP citrate synthase activity was downregulated and glycolytic activity was upregulated in L. betulina. However, the activity of aerobic pathways was decreased and the oxidative branch of the pentose phosphate pathway was redirected form nicotinamide adenine dinucleotide phosphate (NADPH) to minimize endogenous ROS-mediated damage in T. versicolor. Taken together, these observations reveal that OG is a potent inhibitor of white-rot fungus. Further structural optimization research and pharmacological investigations are warranted.

scholarly journals Reactive oxygen species (ROS) mediated enhanced anti-candidal activity of ZnS–ZnO nanocomposites with low inhibitory concentrations

RSC Advances ◽  
2015 ◽  
Vol 5 (94) ◽  
pp. 76718-76728 ◽  
Author(s):  
P. Suyana ◽  
S. Nishanth Kumar ◽  
Nimisha Madhavan ◽  
B. S. Dileep Kumar ◽  
Balagopal N. Nair ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Reactive Oxygen Species ◽  
Candida Albicans ◽  
Antifungal Activity ◽  
Candida Tropicalis ◽  
Yeast Species ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Precipitation Technique

Enhanced antifungal activity against the yeast species Candida albicans, Candida tropicalis and Saccharomyces cerevisiae was displayed by ZnS–ZnO nanocomposites prepared by a simple precipitation technique.

scholarly journals Gene Regulation Shifts Shed Light on Fungal Adaption in Plant Biomass Decomposers

mBio ◽  
2019 ◽  
Vol 10 (6) ◽  
Author(s):  
Jiwei Zhang ◽  
Kevin A. T. Silverstein ◽  
Jesus David Castaño ◽  
Melania Figueroa ◽  
Jonathan S. Schilling
Keyword(s):  
Reactive Oxygen Species ◽  
Gene Regulation ◽  
Plant Biomass ◽  
Reactive Oxygen ◽  
Brown Rot ◽  
Comparative Transcriptomics ◽  
White Rot ◽  
Ecological Niches ◽  
Oxygen Species ◽  
Brown Rot Fungi

ABSTRACT Fungi dominate the recycling of carbon sequestered in woody biomass. This process of organic turnover was first evolved among “white rot” fungi that degrade lignin to access carbohydrates and later evolved multiple times toward more efficient strategies to selectively target carbohydrates—“brown rot.” The brown rot adaption was often explained by mechanisms to deploy reactive oxygen species (ROS) to oxidatively attack wood structures. However, its genetic basis remains unclear, especially in the context of gene contractions of conventional carbohydrate-active enzymes (CAZYs) relative to white rot ancestors. Here, we hypothesized that these apparent gains in brown rot efficiency despite gene losses were due, in part, to upregulation of the retained genes. We applied comparative transcriptomics to multiple species of both rot types grown across a wood wafer to create a gradient of progressive decay and to enable tracking temporal gene expression. Dozens of “decay-stage-dependent” ortho-genes were isolated, narrowing a pool of candidate genes with time-dependent regulation unique to brown rot fungi. A broad comparison of the expression timing of CAZY families indicated a temporal regulatory shift of lignocellulose-oxidizing genes toward early stages in brown rot compared to white rot, enabling the segregation of oxidative treatment ahead of hydrolysis. These key brown rot ROS-generating genes with iron ion binding functions were isolated. Moreover, transcription energy was shifted to be invested on the retained GHs in brown rot fungi to strengthen carbohydrate conversion. Collectively, these results support the hypothesis that gene regulation shifts played a pivotal role in brown rot adaptation. IMPORTANCE Fungi dominate the turnover of wood, Earth’s largest pool of aboveground terrestrial carbon. Fungi first evolved this capacity by degrading lignin to access and hydrolyze embedded carbohydrates (white rot). Multiple lineages, however, adapted faster reactive oxygen species (ROS) pretreatments to loosen lignocellulose and selectively extract sugars (brown rot). This brown rot “shortcut” often coincided with losses (>60%) of conventional lignocellulolytic genes, implying that ROS adaptations supplanted conventional pathways. We used comparative transcriptomics to further pursue brown rot adaptations, which illuminated the clear temporal expression shift of ROS genes, as well as the shift toward synthesizing more GHs in brown rot relative to white rot. These imply that gene regulatory shifts, not simply ROS innovations, were key to brown rot fungal evolution. These results not only reveal an important biological shift among these unique fungi, but they may also illuminate a trait that restricts brown rot fungi to certain ecological niches.

scholarly journals Oxidative Damage Control during Decay of Wood by Brown Rot Fungus Using Oxygen Radicals

2018 ◽  
Vol 84 (22) ◽  
Author(s):  
Jesus D. Castaño ◽  
Jiwei Zhang ◽  
Claire E. Anderson ◽  
Jonathan S. Schilling
Keyword(s):  
Reactive Oxygen Species ◽  
Cell Walls ◽  
Reactive Oxygen ◽  
Brown Rot ◽  
White Rot ◽  
Ros Generation ◽  
Oxygen Species ◽  
Content Type ◽  
Brown Rot Fungi ◽  
Brown Rot Fungus

ABSTRACTBrown rot wood-degrading fungi deploy reactive oxygen species (ROS) to loosen plant cell walls and enable selective polysaccharide extraction. These ROS, including Fenton-generated hydroxyl radicals (HO˙), react with little specificity and risk damaging hyphae and secreted enzymes. Recently, it was shown that brown rot fungi reduce this risk, in part, by differentially expressing genes involved in HO˙ generation ahead of those coding carbohydrate-active enzymes (CAZYs). However, there are notable exceptions to this pattern, and we hypothesized that brown rot fungi would require additional extracellular mechanisms to limit ROS damage. To assess this, we grewPostia placentadirectionally on wood wafers to spatially segregate early from later decay stages. Extracellular HO˙ production (avoidance) and quenching (suppression) capacities among the stages were analyzed, along with the ability of secreted CAZYs to maintain activity postoxidation (tolerance). First, we found that H2O2and Fe2+concentrations in the extracellular environment were conducive to HO˙ production in early (H2O2:Fe2+ratio 2:1) but not later (ratio 1:131) stages of decay. Second, we found that ABTS radical cation quenching (antioxidant capacity) was higher in later decay stages, coincident with higher fungal phenolic concentrations. Third, by surveying enzyme activities before/after exposure to Fenton-generated HO˙, we found that CAZYs secreted early, amid HO˙, were more tolerant of oxidative stress than those expressed later and were more tolerant than homologs in the model CAZY producerTrichoderma reesei. Collectively, this indicates thatP. placentauses avoidance, suppression, and tolerance mechanisms, extracellularly, to complement intracellular differential expression, enabling this brown rot fungus to use ROS to degrade wood.IMPORTANCEWood is one of the largest pools of carbon on Earth, and its decomposition is dominated in most systems by fungi. Wood-degrading fungi specialize in extracting sugars bound within lignin, either by removing lignin first (white rot) or by using Fenton-generated reactive oxygen species (ROS) to “loosen” wood cell walls, enabling selective sugar extraction (brown rot). Although white rot lignin-degrading pathways are well characterized, there are many uncertainties in brown rot fungal mechanisms. Our study addressed a key uncertainty in how brown rot fungi deploy ROS without damaging themselves or the enzymes they secrete. In addition to revealing differentially expressed genes to promote ROS generation only in early decay, our study revealed three spatial control mechanisms to avoid/tolerate ROS: (i) constraining Fenton reactant concentrations (H2O2, Fe2+), (ii) quenching ROS via antioxidants, and (iii) secreting ROS-tolerant enzymes. These results not only offer insight into natural decomposition pathways but also generate targets for biotechnological development.

Antifungal activity of novel synthetic peptides by accumulation of reactive oxygen species (ROS) and disruption of cell wall against Candida albicans

Peptides ◽  
2011 ◽  
Vol 32 (8) ◽  
pp. 1732-1740 ◽  
Author(s):  
Indresh Kumar Maurya ◽  
Sarika Pathak ◽  
Monika Sharma ◽  
Hina Sanwal ◽  
Preeti Chaudhary ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Cell Wall ◽  
Candida Albicans ◽  
Antifungal Activity ◽  
Synthetic Peptides ◽  
Reactive Oxygen ◽  
Oxygen Species

Design and Synthesis of a Series of Piperazine-1-carboxamidine Derivatives with Antifungal Activity Resulting from Accumulation of Endogenous Reactive Oxygen Species

ChemMedChem ◽  
2009 ◽  
Vol 4 (10) ◽  
pp. 1714-1721 ◽  
Author(s):  
Isabelle E. François ◽  
Karin Thevissen ◽  
Klaartje Pellens ◽  
Els M. Meert ◽  
Jan Heeres ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Antifungal Activity ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Design And Synthesis ◽  
Endogenous Reactive Oxygen Species
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