Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

Article Types

Countries / Regions

Search Results (45)

Search Parameters:
Keywords = β-(1,3)-glucan synthase

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
16 pages, 12585 KB  
Article
Structural Features and Anti-Inflammatory Activity of a Low-Molecular-Weight Oligosaccharide Fraction from Lotus Bee Pollen
by Gongliang Liu, Jinxia Guo, Lantao Li, Weidong Bai and Hong Wang
Foods 2026, 15(14), 2512; https://doi.org/10.3390/foods15142512 - 16 Jul 2026
Viewed by 364
Abstract
A novel low-molecular-weight water-soluble oligosaccharide fraction (LBPP-1) was prepared from lotus bee pollen via microwave-assisted extraction, followed by Sevag deproteinization and diethylaminoethyl (DEAE)-cellulose-52 chromatography purification. Ion chromatography (IC) indicated a glucose-rich composition (84.6 mol% glucose), with minor amounts of arabinose, glucosamine, and galactose. [...] Read more.
A novel low-molecular-weight water-soluble oligosaccharide fraction (LBPP-1) was prepared from lotus bee pollen via microwave-assisted extraction, followed by Sevag deproteinization and diethylaminoethyl (DEAE)-cellulose-52 chromatography purification. Ion chromatography (IC) indicated a glucose-rich composition (84.6 mol% glucose), with minor amounts of arabinose, glucosamine, and galactose. Fourier transform-infrared spectroscopy (FT-IR), methylation analysis, and 1H nuclear magnetic resonance (NMR) collectively supported the assignment of LBPP-1 as a glucan-rich, structurally heterogeneous oligosaccharide fraction containing candidate →4)-Glcp-rich domains and minor arabinose/galactose-related linkages. However, the marked difference between the IC composition and the sugar-type distribution estimated from PMAA peak areas limits quantitative interpretation of the residue proportions and branching architecture. Furthermore, in vitro biological assays demonstrated that LBPP-1 significantly attenuated lipopolysaccharide (LPS)-induced inflammatory responses in RAW264.7 macrophages. It effectively reduced the secretion of nitric oxide (NO) and the levels of inducible nitric oxide synthase (iNOS), interleukin (IL)-6, and tumor necrosis factor (TNF)-α in RAW264.7 macrophages. Reverse transcription–quantitative polymerase chain reaction (RT-qPCR) analysis further revealed that LBPP-1 selectively suppressed the mRNA expression of cyclooxygenase-2 (COX-2), IL-1β, IL-6, iNOS, and transforming growth factor (TGF)-β1. These findings collectively suggest that LBPP-1, as a bioactive carbohydrate fraction derived from lotus bee pollen, holds promise as a natural functional food ingredient for managing inflammation-related conditions. Full article
(This article belongs to the Special Issue Bioactive Compounds in Bee Products: From Analysis to Health Benefits)
Show Figures

Graphical abstract

25 pages, 9782 KB  
Article
Small Molecular Peptides and Their Potential Antifungal Activities During the Pile-Fermentation of Post-Fermented Tea
by Xueli Pan, Mengyi Guo, Song Wu, Huan Huang, Yan Luo, Zhenjun Zhao, Xun Chen, Xianchun Hu, Huawei Wu and Xinghui Li
Foods 2026, 15(7), 1263; https://doi.org/10.3390/foods15071263 - 7 Apr 2026
Viewed by 760
Abstract
This study systematically investigated the dynamic diversity, potential sources, and antifungal activities of small molecular peptides during the pile-fermentation process of post-fermented tea. By analyzing the damaging effects of small molecular peptide extracts from tea samples at different pile-fermentation stages on the spore [...] Read more.
This study systematically investigated the dynamic diversity, potential sources, and antifungal activities of small molecular peptides during the pile-fermentation process of post-fermented tea. By analyzing the damaging effects of small molecular peptide extracts from tea samples at different pile-fermentation stages on the spore cell membranes of Aspergillus carbonarius (A. carbonarius) and the inhibitory activity against β-1,3-glucan synthase (β-1,3-GS), it was confirmed that some small molecular peptides exhibit significant antifungal effects. The main findings are as follows: (1) The number of identified small molecular peptides showed a trend of first increasing and then decreasing with the progress of pile-fermentation, peaking at 4453 species on the 35th day of pile-fermentation, and were dominated by hexapeptides and heptapeptides with molecular weights ranging from 600 to 800 Da. (2) Based on orthogonal partial least squares discriminant analysis (OPLS-DA), the samples were divided into three characteristic stages according to the differences in small molecular peptide composition at different stages, and 156 characteristic peptides with a relative abundance higher than 0.1% were screened out. Their precursor proteins were derived from 148 proteins belonging to 16 genera, including Camellia, Aspergillus, Saccharomyces, Penicillium, and Bacillus. (3) BLAST alignment results showed that five out of the 156 characteristic peptides were degradation fragments of known antifungal peptides originating from Aspergillus and Bacillus. (4) Combining molecular docking screening and in vitro verification of synthetic peptides, a total of 27 small molecular peptides with antifungal activity were obtained, and their mechanism of action was the inhibition of β-1,3-GS activity. (5) The small molecular peptides related to antifungal activity could be classified into two categories: enzymatic hydrolysates of known antifungal peptides, and the enzymatic hydrolysates of tea-derived proteins or macromolecular peptides. Both categories were mainly distributed in the three stages of pile-fermentation, and there was a significant positive correlation among the population size of dominant microorganisms, microbial peptidase activity, and the abundance of small molecular peptides. This study reveals the dynamic generation pattern and antifungal potential of small molecular peptides during the pile-fermentation of post-fermented tea, providing a new scientific basis for evaluating the dynamic changes in microbial communities in tea and effectively controlling the contamination of harmful fungi during the pile-fermentation process. Full article
Show Figures

Figure 1

19 pages, 2690 KB  
Article
Integrated Metabolomics and Proteomics Analyses of the Grain-Filling Process and Differences in the Quality of Tibetan Hulless Barleys
by Yanrong Pang, Yuping Yang, Kaifeng Zheng, Xiaozhuo Wu, Yanfen Zhang, Jinyuan Chen, Guigong Geng, Feng Qiao and Shengcheng Han
Plants 2025, 14(13), 1946; https://doi.org/10.3390/plants14131946 - 25 Jun 2025
Cited by 1 | Viewed by 1408
Abstract
Tibetan hulless barley (qingke) grains are becoming more popular because of their high nutritional benefits. Comparative metabolomics and proteomics analyses of qingke grains (at 16, 20, 36, and 42 days after flowering) were conducted to explore the metabolic dynamics during grain filling and [...] Read more.
Tibetan hulless barley (qingke) grains are becoming more popular because of their high nutritional benefits. Comparative metabolomics and proteomics analyses of qingke grains (at 16, 20, 36, and 42 days after flowering) were conducted to explore the metabolic dynamics during grain filling and compare the differences in quality among three different varieties, Dulihuang, Kunlun 14, and Heilaoya. A total of 728 metabolites and 4864 proteins were identified. We first found that both the metabolite and protein profiles were more closely associated with the grain developmental stage in each cultivar than across different stages in a single cultivar. Next, we focused on the energy metabolism and biosynthesis pathways of key quality components, such as flavonoids, starch, and β-glucans in qingke grains. Quantitative analysis revealed significant variation in the abundance of cellulose synthase-like enzyme (CslF) among the three cultivars. Notably, Heilaoya displayed substantially lower CslF6 levels at 36 and 42 DAF than Kunlun 14 and Dulihuang did. These observed differences in CslF6 abundance may represent a key regulatory mechanism underlying the distinct β-glucan biosynthesis patterns among the three cultivars. Collectively, our results enhance the understanding of metabolic networks involved in qingke grain development and serve as a foundation for advancing breeding studies. Full article
(This article belongs to the Collection Feature Papers in Plant Physiology and Metabolism)
Show Figures

Figure 1

16 pages, 14665 KB  
Article
The Membrane-Targeting Synergistic Antifungal Effects of Walnut-Derived Peptide and Salicylic Acid on Prickly Pear Spoilage Fungus
by Yue Hu, Na Liu, Caiqing Ma, Difeng Ren, Dujun Wang, Yueling Shang, Fengwei Li, Yongmei Lyu, Chen Cai, Long Chen, Wenjing Liu and Xiaohong Yu
Foods 2025, 14(6), 951; https://doi.org/10.3390/foods14060951 - 11 Mar 2025
Cited by 2 | Viewed by 1648
Abstract
Fermented walnut (FW) meal exhibits antifungal activity against Penicillium victoriae (the fungus responsible for prickly pear spoilage), which is mainly attributed to the synergistic effect of antimicrobial peptides and salicylic acid (SA). This study aimed to investigate the synergistic mechanism between YVVPW (YW-5, [...] Read more.
Fermented walnut (FW) meal exhibits antifungal activity against Penicillium victoriae (the fungus responsible for prickly pear spoilage), which is mainly attributed to the synergistic effect of antimicrobial peptides and salicylic acid (SA). This study aimed to investigate the synergistic mechanism between YVVPW (YW-5, the peptide with the highest antifungal activity) and SA against the cell membrane of P. victoriae. Treatment enhanced prickly pear’s rot rate, polyphenol concentration, and superoxide dismutase (SOD) activity by 38.11%, 8.11%, and 48.53%, respectively, while reducing the microbial count by 19.17%. Structural analyses revealed β-sheets as YW-5′s predominant structure (41.18%), which increased to 49.0% during SA interaction. Molecular docking demonstrated YW-5′s stronger binding to β-(1,3)-glucan synthase and membrane protein amino acids via hydrogen bonds, hydrophobic forces, and π-π conjugate interactions. Spectroscopic analyses demonstrated SA’s major role in YW-5 synergy at the interface and polar head region of phospholipids, enhancing lipid chain disorder and the leakage of cell components. Malondialdehyde and SOD levels increased nearly two-fold and six-fold when treated with YW-5/SA, and YW-5 showed a more pronounced effect. Scanning electron and transmission electron microscopy confirmed that SA caused greater damage to spore morphology and cell ultrastructure. These findings support this formulation’s functions as an efficient antifungal substance in fruit storage. Full article
(This article belongs to the Section Food Quality and Safety)
Show Figures

Figure 1

19 pages, 4807 KB  
Article
Optimization of Protoplast Preparation Conditions in Lyophyllum decastes and Transcriptomic Analysis Throughout the Process
by Xiaobin Li, Ying Qin, Yufei Kong, Samantha Chandranath Karunarathna, Yunjiang Liang and Jize Xu
J. Fungi 2024, 10(12), 886; https://doi.org/10.3390/jof10120886 - 21 Dec 2024
Cited by 14 | Viewed by 2722
Abstract
Protoplasts are essential tools for genetic manipulation and functional genomics research in fungi. This study systematically optimized protoplast preparation conditions and examined transcriptional changes throughout the preparation and regeneration processes to elucidate the molecular mechanisms underlying the formation and regeneration of protoplasts in [...] Read more.
Protoplasts are essential tools for genetic manipulation and functional genomics research in fungi. This study systematically optimized protoplast preparation conditions and examined transcriptional changes throughout the preparation and regeneration processes to elucidate the molecular mechanisms underlying the formation and regeneration of protoplasts in Lyophyllum decastes. The results indicated an optimal protoplast yield of 5.475 × 106 cells/mL under conditions of fungal age at 10 days, digestion time of 2.25 h, enzyme concentration of 2%, and digestion temperature of 28 °C. The Z5 medium supplemented with L. decastes mycelial extract achieved a high regeneration rate of 2.86. RNA-seq analysis revealed 2432 differentially expressed genes (DEGs) during protoplast formation and 5825 DEGs during regeneration. Casein kinase I, cytochrome P450 (CYP52), and redox-regulated input receptor (PEX5) were significantly upregulated during the protoplast stage, while β-1,3-glucan synthase (SKN1), chitin synthase (CHS2), hydrophobin-1, and hydrophobin-2 showed significant upregulation during the protoplast regeneration phase. These findings provide a reference for the efficient preparation and regeneration of protoplasts and offer new insights into the molecular mechanisms of protoplast formation and cell wall regeneration in fungi. Full article
(This article belongs to the Special Issue Current Trends in Mycological Research in Southeast Asia)
Show Figures

Figure 1

15 pages, 4248 KB  
Article
Globospiramine Exhibits Inhibitory and Fungicidal Effects against Candida albicans via Apoptotic Mechanisms
by Joe Anthony H. Manzano, Simone Brogi, Vincenzo Calderone, Allan Patrick G. Macabeo and Nicanor Austriaco
Biomolecules 2024, 14(6), 610; https://doi.org/10.3390/biom14060610 - 22 May 2024
Cited by 9 | Viewed by 4108
Abstract
Candidiasis is considered an emerging public health concern because of the occurrence of drug-resistant Candida strains and the lack of an available structurally diverse antifungal drug armamentarium. The indole alkaloid globospiramine from the anticandidal Philippine medicinal plant Voacanga globosa exhibits a variety of [...] Read more.
Candidiasis is considered an emerging public health concern because of the occurrence of drug-resistant Candida strains and the lack of an available structurally diverse antifungal drug armamentarium. The indole alkaloid globospiramine from the anticandidal Philippine medicinal plant Voacanga globosa exhibits a variety of biological activities; however, its antifungal properties remain to be explored. In this study, we report the in vitro anticandidal activities of globospiramine against two clinically relevant Candida species (C. albicans and C. tropicalis) and the exploration of its possible target proteins using in silico methods. Thus, the colony-forming unit (CFU) viability assay revealed time- and concentration-dependent anticandidal effects of the alkaloid along with a decrease in the number of viable CFUs by almost 50% at 60 min after treatment. The results of the MIC and MFC assays indicated inhibitory and fungicidal effects of globospiramine against C. albicans (MIC = 8 µg/mL; MFC = 8 µg/mL) and potential fungistatic effects against C. tropicalis at lower concentrations (MIC = 4 µg/mL; MFC > 64 µg/mL). The FAM-FLICA poly-caspase assay showed metacaspase activation in C. albicans cells at concentrations of 16 and 8 µg/mL, which agreed well with the MIC and MFC values. Molecular docking and molecular dynamics simulation experiments suggested globospiramine to bind strongly with 1,3-β-glucan synthase and Als3 adhesin—enzymes indirectly involved in apoptosis-driven candidal inhibition. Full article
Show Figures

Figure 1

20 pages, 2750 KB  
Article
Metagenomic Insights into the Taxonomic and Functional Features of Traditional Fermented Milk Products from Russia
by Alexander G. Elcheninov, Kseniya S. Zayulina, Alexandra A. Klyukina, Mariia K. Kremneva, Ilya V. Kublanov and Tatiana V. Kochetkova
Microorganisms 2024, 12(1), 16; https://doi.org/10.3390/microorganisms12010016 - 21 Dec 2023
Cited by 26 | Viewed by 5239
Abstract
Fermented milk products (FMPs) contain probiotics that are live bacteria considered to be beneficial to human health due to the production of various bioactive molecules. In this study, nine artisanal FMPs (kefir, ayran, khurunga, shubat, two cottage cheeses, bryndza, khuruud and suluguni-like cheese) [...] Read more.
Fermented milk products (FMPs) contain probiotics that are live bacteria considered to be beneficial to human health due to the production of various bioactive molecules. In this study, nine artisanal FMPs (kefir, ayran, khurunga, shubat, two cottage cheeses, bryndza, khuruud and suluguni-like cheese) from different regions of Russia were characterized using metagenomics. A metagenomic sequencing of ayran, khurunga, shubat, khuruud and suluguni-like cheese was performed for the first time. The taxonomic profiling of metagenomic reads revealed that Lactococcus species, such as Lc. lactis and Lc. cremoris prevailed in khuruud, bryndza, one sample of cottage cheese and khurunga. The latter one together with suluguni-like cheese microbiome was dominated by bacteria, affiliated to Lactobacillus helveticus (32–35%). In addition, a high proportion of sequences belonging to the genera Lactobacillus, Lactococcus and Streptococcus but not classified at the species level were found in the suluguni-like cheese. Lactobacillus delbrueckii, as well as Streptococcus thermophilus constituted the majority in another cottage cheese, kefir and ayran metagenomes. The microbiome of shubat, produced from camel’s milk, was significantly distinctive, and Lentilactobacillus kefiri, Lactobacillus kefiranofaciens and Bifidobacterium mongoliense represented the dominant components (42, 7.4 and 5.6%, respectively). In total, 78 metagenome-assembled genomes with a completeness ≥ 50.2% and a contamination ≤ 8.5% were recovered: 61 genomes were assigned to the Enterococcaceae, Lactobacillaceae and Streptococcaceae families (the Lactobacillales order within Firmicutes), 4 to Bifidobacteriaceae (the Actinobacteriota phylum) and 2 to Acetobacteraceae (the Proteobacteria phylum). A metagenomic analysis revealed numerous genes, from 161 to 1301 in different products, encoding glycoside hydrolases and glycosyltransferases predicted to participate in lactose, alpha-glucans and peptidoglycan hydrolysis as well as exopolysaccharides synthesis. A large number of secondary metabolite biosynthetic gene clusters, such as lanthipeptides, unclassified bacteriocins, nonribosomal peptides and polyketide synthases were also detected. Finally, the genes involved in the synthesis of bioactive compounds like β-lactones, terpenes and furans, nontypical for fermented milk products, were also found. The metagenomes of kefir, ayran and shubat was shown to contain either no or a very low count of antibiotic resistance genes. Altogether, our results show that traditional indigenous fermented products are a promising source of novel probiotic bacteria with beneficial properties for medical and food industries. Full article
Show Figures

Figure 1

20 pages, 5631 KB  
Article
Based on Transcriptome Sequencing of Cell Wall Deficient Strain, Research on Arabinosyltransferase Inhibition’s Effect on the Synthesis of Cell Wall in Chlamydomonas reinhardtii
by Wenhua Zhang, Menghui Shang, Lexin Qiu, Bin Liu and Xiaonan Zang
Int. J. Mol. Sci. 2023, 24(24), 17595; https://doi.org/10.3390/ijms242417595 - 18 Dec 2023
Cited by 3 | Viewed by 2197
Abstract
To explore the key genes involved in cell wall synthesis and understand the molecular mechanism of cell wall assembly in the model alga-Chlamydomonas reinhardtii, transcriptome sequencing was used to discover the differentially expressed genes in the cell wall defective strain. In [...] Read more.
To explore the key genes involved in cell wall synthesis and understand the molecular mechanism of cell wall assembly in the model alga-Chlamydomonas reinhardtii, transcriptome sequencing was used to discover the differentially expressed genes in the cell wall defective strain. In the glucose metabolism, lipid metabolism, and amino acid metabolism pathways, the gene expressions involved in the synthesis of cell wall functional components were analyzed. The results showed that in the cell wall defective strain, arabinosyltransferase gene (XEG113, RRA) related to synthesis of plant extensin and some cell wall structural protein genes (hyp, PHC19, PHC15, PHC4, PHC3) were up-regulated, 1,3-β-glucan synthase gene (Gls2) and endoglucanase gene (EG2) about synthesis and degradation of glycoskeleton were both mainly up-regulated. Then, ethambutol dihydrochloride, an arabinosyltransferase inhibitor, was found to affect the permeability of the cell wall of the normal strain, while the cell wall deficient strain was not affected. To further research the function of arabinosyltransferase, the RRA gene was inactivated by knockout in the normal cell wall algal strain. Through a combination of microscope observation and physiological index detection, it was found that the cell wall of the mutant strains showed reduced structure levels, suggesting that the structure and function of the cell wall glycoprotein were weakened. Therefore, arabinosyltransferase may affect the glycosylation modification of cell wall glycoprotein, further affecting the structure assembly of cell wall glycoprotein. Full article
(This article belongs to the Special Issue Latest Research on Plant Cell Wall)
Show Figures

Figure 1

41 pages, 6786 KB  
Article
Boswellia Essential Oil: Natural Antioxidant as an Effective Antimicrobial and Anti-Inflammatory Agent
by Diana Obiștioiu, Anca Hulea, Ileana Cocan, Ersilia Alexa, Monica Negrea, Iuliana Popescu, Viorel Herman, Ilinca Merima Imbrea, Gabriel Heghedus-Mindru, Mukhtar Adeiza Suleiman, Isidora Radulov and Florin Imbrea
Antioxidants 2023, 12(10), 1807; https://doi.org/10.3390/antiox12101807 - 27 Sep 2023
Cited by 29 | Viewed by 8410
Abstract
The research aimed to determine the chemical composition, the antioxidant and anti-inflammatory activity as well as the antimicrobial activity against Gram-positive, Gram-negative and two fungal Candida ATCC strains of a commercial Boswellia essential oil (BEO) containing Boswellia carteri, Boswellia sacra, Boswellia [...] Read more.
The research aimed to determine the chemical composition, the antioxidant and anti-inflammatory activity as well as the antimicrobial activity against Gram-positive, Gram-negative and two fungal Candida ATCC strains of a commercial Boswellia essential oil (BEO) containing Boswellia carteri, Boswellia sacra, Boswellia papryfera, and Boswellia frereana. Additionally, molecular docking was carried out to show the molecular dynamics of the compounds identified from the essential oil against three bacterial protein targets and one fungal protein target. The major components identified by GC-MS (Gas Chromatography-Mass Spectrometry) were represented by α-pinene, followed by limonene. Evaluation of antioxidant activity using the DPPH (2,2-Diphenyl-1-Picrylhydrazyl) method showed high inhibition comparable to the synthetic antioxidant used as a control. Oxidative stability evaluation showed that BEO has the potential to inhibit primary and secondary oxidation products with almost the same efficacy as butylated hydroxyanisole (BHA). The use of BEO at a concentration of 500 ppm provided the best protection against secondary oxidation during 30 days of storage at room temperature, which was also evident in the peroxide value. Regarding the in vitro anti-inflammatory activity, the membrane lysis assay and the protein denaturation test revealed that even if the value of protection was lower than the value registered in the case of dexamethasone, the recommendation of using BEO as a protective agent stands, considering the lower side effects. Gram-positive bacteria proved more sensitive, while Pseudomonas aeruginosa presented different sensitivity, with higher MICs (minimal inhibitory concentration). Haemophilus influenzae demonstrated a MIC at 2% but with consecutive inhibitory values in a negative correlation with the increase in concentration, in contrast to E. coli, which demonstrated low inhibitory rates at high concentrations of BEO. The computational tools employed revealed interesting binding energies with compounds having low abundance. The interaction of these compounds and the proteins (tyrosyl-tRNA synthetase, DNA gyrase, peptide deformylase, 1,3-β-glucan synthase) predicts hydrogen bonds with amino acid residues, which are reported in the active sites of the proteins. Even so, compounds with low abundance in BEO could render the desired bioactive properties to the overall function of the oil sustained by physical factors such as storage and temperature. Interestingly, the findings from this study demonstrated the antioxidant and antimicrobial potential of Boswellia essential oil against food-related pathogens, thus making the oil a good candidate for usage in food, feed or food-safety-related products. Full article
(This article belongs to the Special Issue Antioxidant Potential in Medicinal Plants)
Show Figures

Figure 1

25 pages, 5125 KB  
Article
Exploration of Baicalein-Core Derivatives as Potent Antifungal Agents: SAR and Mechanism Insights
by Heyang Zhou, Niao Yang, Wei Li, Xuemi Peng, Jiaxiao Dong, Yuanying Jiang, Lan Yan, Dazhi Zhang and Yongsheng Jin
Molecules 2023, 28(17), 6340; https://doi.org/10.3390/molecules28176340 - 30 Aug 2023
Cited by 8 | Viewed by 3311
Abstract
Baicalein (BE), the major component of Scutellaria Baicalensis, exhibited potently antifungal activity against drug-resistant Candida albicans, and strong inhibition on biofilm formation. Therefore, a series of baicalein-core derivatives were designed and synthesized to find more potent compounds and investigate [...] Read more.
Baicalein (BE), the major component of Scutellaria Baicalensis, exhibited potently antifungal activity against drug-resistant Candida albicans, and strong inhibition on biofilm formation. Therefore, a series of baicalein-core derivatives were designed and synthesized to find more potent compounds and investigate structure–activity relationship (SAR) and mode of action (MoA). Results demonstrate that A4 and B5 exert a more potent antifungal effect (MIC80 = 0.125 μg/mL) than BE (MIC80 = 4 μg/mL) when used in combination with fluconazole (FLC), while the MIC80 of FLC dropped from 128 μg/mL to 1 μg/mL. SAR analysis indicates that the presence of 5-OH is crucial for synergistic antifungal activities, while o-dihydroxyls and vic-trihydroxyls are an essential pharmacophore, whether they are located on the A ring or the B ring of flavonoids. The MoA demonstrated that these compounds exhibited potent antifungal effects by inhibiting hypha formation of C. albicans. However, sterol composition assay and enzymatic assay conducted in vitro indicated minimal impact of these compounds on sterol biosynthesis and Eno1. These findings were further confirmed by the results of the in-silico assay, which assessed the stability of the complexes. Moreover, the inhibition of hypha of this kind of compound could be attributed to their effect on the catalytic subunit of 1,3-β-d-glucan synthase, 1,3-β-d-glucan-UDP glucosyltransferase and glycosyl-phosphatidylinositol protein, rather than inhibiting ergosterol biosynthesis and Eno1 activity by Induced-Fit Docking and Molecular Dynamics Simulations. This study presents potential antifungal agents with synergistic effects that can effectively inhibit hypha formation. It also provides new insights into the MoA. Full article
Show Figures

Graphical abstract

16 pages, 1418 KB  
Article
In Vitro Killing Activities of Anidulafungin and Micafungin with and without Nikkomycin Z against Four Candida auris Clades
by Awid Adnan, Andrew M. Borman, Zoltán Tóth, Lajos Forgács, Renátó Kovács, Dávid Balázsi, Bence Balázs, Gergely Udvarhelyi, Gábor Kardos and László Majoros
Pharmaceutics 2023, 15(5), 1365; https://doi.org/10.3390/pharmaceutics15051365 - 29 Apr 2023
Cited by 7 | Viewed by 2862
Abstract
Candida auris is a multidrug-resistant pathogen against which echinocandins are the drug of choice. However, information on how the chitin synthase inhibitor nikkomycin Z influences the killing activities of echinocandins against C. auris is currently lacking. We determined the killing activities of anidulafungin [...] Read more.
Candida auris is a multidrug-resistant pathogen against which echinocandins are the drug of choice. However, information on how the chitin synthase inhibitor nikkomycin Z influences the killing activities of echinocandins against C. auris is currently lacking. We determined the killing activities of anidulafungin and micafungin (0.25, 1, 8, 16 and 32 mg/L each) with and without nikkomycin Z (8 mg/L) against 15 isolates representing four C. auris clades (South Asian n = 5; East Asian n = 3; South African n = 3; South American n = 4, two of which were of environmental origin). Two and one isolates from the South Asian clade harbored mutations in the hot-spot 1 (S639Y and S639P) and 2 (R1354H) regions of the FKS1 gene, respectively. The anidulafungin, micafungin and nikkomycin Z MIC ranges were 0.015-4, 0.03-4 and 2->16 mg/L, respectively. Anidulafungin and micafungin alone exerted weak fungistatic activity against wild-type isolates and the isolate with a mutation in the hot-spot 2 region of FKS1 but was ineffective against the isolates with a mutation in the hot-spot 1 region. The nikkomycin Z killing curves were always similar to their respective controls. Twenty-two of sixty (36.7%) anidulafungin plus nikkomycin Z and twenty-four of sixty (40%) micafungin plus nikkomycin Z combinations produced at least 100-fold decreases in the CFUs (synergy), with a 41.7% and 20% fungicidal effect, respectively, against wild-type isolates. Antagonism was never observed. Similar results were found with the isolate with a mutation in hot-spot 2 of FKS1, but the combinations were ineffective against the two isolates with prominent mutations in hot-spot 1 of FKS1. The simultaneous inhibition of β-1,3 glucan and chitin synthases in wild-type C. auris isolates produced significantly greater killing rates than either drug alone. Further studies are warranted to verify the clinical efficacy of echinocandin plus nikkomycin Z combinations against echinocandin susceptible C. auris isolates. Full article
(This article belongs to the Section Pharmacokinetics and Pharmacodynamics)
Show Figures

Figure 1

19 pages, 1429 KB  
Review
The Mushroom Glucans: Molecules of High Biological and Medicinal Importance
by János Vetter
Foods 2023, 12(5), 1009; https://doi.org/10.3390/foods12051009 - 27 Feb 2023
Cited by 120 | Viewed by 19105
Abstract
Carbohydrates, including polysaccharide macromolecules, are the main constituents of the fungal cell wall. Among these, the homo- or heteropolymeric glucan molecules are decisive, as they not only protect fungal cells but also have broad, positive biological effects on the animal and human bodies. [...] Read more.
Carbohydrates, including polysaccharide macromolecules, are the main constituents of the fungal cell wall. Among these, the homo- or heteropolymeric glucan molecules are decisive, as they not only protect fungal cells but also have broad, positive biological effects on the animal and human bodies. In addition to the beneficial nutritional properties of mushrooms (mineral elements, favorable proteins, low fat and energy content, pleasant aroma, and flavor), they have a high glucan content. Folk medicine (especially in the Far East) used medicinal mushrooms based on previous experience. At the end of the 19th century, but mainly since the middle of the 20th century, progressively more scientific information has been published. Glucans from mushrooms are polysaccharides that contain sugar chains, sometimes of only one kind (glucose), sometimes having several monosaccharide units, and they have two (α and β) anomeric forms (isomers). Their molecular weights range from 104 to 105 Da, and rarely 106 Da. X-ray diffraction studies were the first to determine the triple helix configuration of some glucans. It seems that the existence and integrity of the triple helix structure are criteria for their biological effects. Different glucans can be isolated from different mushroom species, and several glucan fractions can be obtained. The biosynthesis of glucans takes place in the cytoplasm, the processes of initiation and then chain extension take place with the help of the glucan synthase enzyme complex (EC 2.4.1.34), and the sugar units are provided by sugar donor UDPG molecules. The two methods used today for glucan determination are the enzymatic and Congo red methods. True comparisons can only be made using the same method. Congo red dye reacts with the tertiary triple helix structure, and the resulting glucan content better reflects the biological value of glucan molecules. The biological effect of β-glucan molecules is proportional to the integrity of the tertiary structure. The glucan contents of the stipe exceed the values of the caps. The glucan levels of individual fungal taxa (including varieties) differ quantitatively and qualitatively. This review presents in more detail the glucans of lentinan (from Lentinula edodes), pleuran (from Pleurotus ostreatus), grifolan (from Grifola frondose), schizophyllan (from Schizophyllum commune), and krestin (from Trametes versicolor), along with their main biological effects. Full article
Show Figures

Figure 1

23 pages, 7750 KB  
Article
Analysis of the Localization of Schizosaccharomyces pombe Glucan Synthases in the Presence of the Antifungal Agent Caspofungin
by Esther San-Quirico, M. Ángeles Curto, Laura Gómez-Delgado, M. Belén Moreno, Pilar Pérez, Juan Carlos Ribas and Juan Carlos G. Cortés
Int. J. Mol. Sci. 2023, 24(5), 4299; https://doi.org/10.3390/ijms24054299 - 21 Feb 2023
Cited by 1 | Viewed by 2721
Abstract
In recent years, invasive fungal infections have emerged as a common source of infections in immunosuppressed patients. All fungal cells are surrounded by a cell wall that is essential for cell integrity and survival. It prevents cell death and lysis resulting from high [...] Read more.
In recent years, invasive fungal infections have emerged as a common source of infections in immunosuppressed patients. All fungal cells are surrounded by a cell wall that is essential for cell integrity and survival. It prevents cell death and lysis resulting from high internal turgor pressure. Since the cell wall is not present in animal cells, it is an ideal target for selective invasive fungal infection treatments. The antifungal family known as echinocandins, which specifically inhibit the synthesis of the cell wall β(13)glucan, has been established as an alternative treatment for mycoses. To explore the mechanism of action of these antifungals, we analyzed the cell morphology and glucan synthases localization in Schizosaccharomyces pombe cells during the initial times of growth in the presence of the echinocandin drug caspofungin. S. pombe are rod-shaped cells that grow at the poles and divide by a central division septum. The cell wall and septum are formed by different glucans, which are synthesized by four essential glucan synthases: Bgs1, Bgs3, Bgs4, and Ags1. Thus, S. pombe is not only a perfect model for studying the synthesis of the fungal β(1-3)glucan, but also it is ideal for examining the mechanisms of action and resistance of cell wall antifungals. Herein, we examined the cells in a drug susceptibility test in the presence of either lethal or sublethal concentrations of caspofungin, finding that exposure to the drug for long periods at high concentrations (>10 µg/mL) induced cell growth arrest and the formation of rounded, swollen, and dead cells, whereas low concentrations (<10 µg/mL) permitted cell growth with a mild effect on cell morphology. Interestingly, short-term treatments with either high or low concentrations of the drug induced effects contrary to those observed in the susceptibility tests. Thus, low drug concentrations induced a cell death phenotype that was not observed at high drug concentrations, which caused transient fungistatic cell growth arrest. After 3 h, high concentrations of the drug caused the following: (i) a decrease in the GFP-Bgs1 fluorescence level; (ii) altered locations of Bgs3, Bgs4, and Ags1; and (iii) a simultaneous accumulation of cells with calcofluor-stained incomplete septa, which at longer times resulted in septation uncoupling from plasma membrane ingression. The incomplete septa revealed with calcofluor were found to be complete when observed via the membrane-associated GFP-Bgs or Ags1-GFP. Finally, we found that the accumulation of incomplete septa depended on Pmk1, the last kinase of the cell wall integrity pathway. Full article
(This article belongs to the Special Issue State-of-the-Art Molecular Microbiology in Spain)
Show Figures

Figure 1

12 pages, 3129 KB  
Article
Comparative Transcriptome Analysis Reveals OsBGs and OsGSLs Influence Sugar Transport through Callose Metabolism under Heat Stress in Rice
by Ruiwei Luan, Jingyang Liu, Longxing Tao, Guanfu Fu and Caixia Zhang
Int. J. Mol. Sci. 2023, 24(4), 3175; https://doi.org/10.3390/ijms24043175 - 6 Feb 2023
Cited by 3 | Viewed by 2821
Abstract
Heat or high temperature stress have caused huge damage to many crops and have become the largest threat in terms of the future. Although a huge amount of research has been conducted to explore the mechanisms of heat tolerance and many achievements were [...] Read more.
Heat or high temperature stress have caused huge damage to many crops and have become the largest threat in terms of the future. Although a huge amount of research has been conducted to explore the mechanisms of heat tolerance and many achievements were accomplished, the mechanism by which how heat stress (HS) influences the yield is still unclear. In this study, RNA-seq analysis indicated that nine 1,3-β-glucanases (BGs) belonging to the carbohydrate metabolic pathway were expressed differently during heat treatment. Therefore, we identified the BGs and glucan-synthase-likes (GSLs) in three rice ecotypes and processed the analyses of gene gain and loss, phylogenetic relationship, duplication, and syntenic relationship. We found the possibility of an environmental adaption based on BGs and GSLs during evolution. Submicrostructure and dry matter distribution analysis confirmed that HS might block the endoplasmic sugar transport pathway by increasing callose synthesis, which may lead to decreased yield and quality in rice production. This study provides a new clue regarding rice yield and quality under HS and provides guidance to rice cultivation and heat tolerance breeding. Full article
(This article belongs to the Special Issue How Rice Plants Response to Abiotic Stresses)
Show Figures

Figure 1

22 pages, 3315 KB  
Article
Potential Treatment of Dermatophyte Trichophyton rubrum in Rat Model Using Topical Green Biosynthesized Silver Nanoparticles with Achillea santolina Extract
by Basem M. Abdallah, Peramaiyan Rajendran and Enas M. Ali
Molecules 2023, 28(4), 1536; https://doi.org/10.3390/molecules28041536 - 5 Feb 2023
Cited by 25 | Viewed by 5838
Abstract
Trichophyton rubrum is the most common dermatophyte, and can cause cutaneous infections in humans and animals (dermatophytosis). In this study, we investigated the anti-dermatophytic potential of green synthesized silver nanoparticles using Achillea santolina extract (AS-AgNPs) in an in vitro and in vivo rat [...] Read more.
Trichophyton rubrum is the most common dermatophyte, and can cause cutaneous infections in humans and animals (dermatophytosis). In this study, we investigated the anti-dermatophytic potential of green synthesized silver nanoparticles using Achillea santolina extract (AS-AgNPs) in an in vitro and in vivo rat model of dermal T. rubrum dermatophytosis (TRD). The green synthesis of AS-AgNPs was performed using A. santolina extract and characterized by UV-VIS spectroscopy, zeta potential, imaging (transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Energy dispersive X-ray analysis (EDX). The antifungal activity of AS-AgNPs was determined by the broth microdilution method, conidial germination, and hyphal growth inhibition. TEM and SEM were used to study the mode of the antifungal action of AS-AgNPs. AS-AgNPs inhibited the growth of T. rubrum with an MIC of 128 μg/mL, and suppressed the conidial germination and hyphal growth by 55.3% 84.6%, respectively. AS-AgNPs caused modified mycelial structures, increased cell membrane permeability, and cell wall damage. AS-AgNPs significantly increase the permeability of the fungal membrane, as revealed by reducing ergosterol biosynthesis. An increase in the intracellular ROS and the induction of apoptosis were also observed during AS-AgNP treatment. In addition, AS-AgNPs reduced the cell wall integrity, as shown by the reduction in the β-(1,3)-d-glucan synthase and chitin synthase activities. AS-AgNPs showed very low toxicity on primary human dermal fibroblasts (HDF) at the MIC. The topical treatment of the infected skin in the TRD rat model with AS-AgNPs showed a significant reduction in the fugal burden after 7 days and a complete clearance of fungal conidia, with a high recovery of epidermal and dermal structures after 14 days, compared to control rats. Interestingly, AS-AgNPs significantly attenuated the infiltrated inflammatory cells, in association with reducing the tissue proinflammatory cytokines including TNF-α, IL-1, IL-6, MOP and IL-17. In conclusion, our data prove AS-AgNPs to be a novel green topical therapy for dermatophytosis caused by T. rubrum. Full article
(This article belongs to the Section Nanochemistry)
Show Figures

Figure 1

Back to TopTop