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This study was conducted with the aim of isolating endophytic fungi from some xerophyte plants. In this study, three fungi were isolated from the internal tissues of some plants spread in the city of Basrah, Xenomyrothecium tongaense from the stem of Suaeda aegyptiace, Chaetomium megalocarpum from the roots, stem and leaves of Caroxylon jordanicola and Cephaliophora irregularis from the leaves of Cressa cretica. Fungus was identified based on its morphological features and molecular based on the amplification of the ITS gene region and the nucleolide sequence of the fungi was deposited in the genebank under accession number NR154511.1, KT371335.1 and OM245865.1 for fungi Xenomyrothecium tongaense, Chaetomium megalocarpum and Cephaliophora irregularis, respectively. This is the first study in which these fungi are isolated from desert in Iraq. [ABSTRACT FROM AUTHOR]

Rosa‐associated fungi are rich in species and diverse in function, with many potential new taxa. However, only a few publications have reported Rosa‐associated endophytic fungi using a combination of molecular systematics and morphology. Rosa roxburghii is an economically important source of medicine and food. We reported earlier the diversity and antimicrobial activities of the fungal endophytes of this plant, but further confirmation is needed for possible new taxa. In this study, we describe 10 novel species and two new host records isolated from healthy tissues of R. roxburghii while identifying three new combinations, all belonging to the Sordariomycetes. The new species described herein include Chaetomium rosifloricola, Chaetomium rosiradicicola, Chrysofolia fructicola, Coniella cili, Hypoxylon florendophyticum, Hypoxylon rosicaulendophyticum, Ilyonectria radicigena, Neopestalotiopsis caulicola, Neopestalotiopsis fructicola, and Seimatosporium endophyticum. Monochaetia bulbophylli, Neopestalotiopsis anacardii, and Neopestalotiopsis termitarii were introduced as new combinations, while Coniella quercicola and Hypoxylon pulicicidum were described as new host records on R. roxburghii. All the taxa have been described, illustrated, and phylogenetically analyzed, in addition to the lifestyles of each genus. Altogether, the results of this study have important implications for identifying novel endophytic fungi and developing potential applications of these fungi in the future. [ABSTRACT FROM AUTHOR]

The endophytic fungus Chaetomium nigricolor culture filtrate's hexane extract was used to identify a cytotoxic very long-chain fatty acid. Based on multiple spectroscopic investigations, the structure of the compound was predicted to be an unsaturated fatty acid, Nonacosenoic acid (NA). Using the MTT assay, the compound's cytotoxic potential was evaluated against MCF-7, A-431, U-251, and HEK-293 T cells. The compound was moderately cytotoxic to breast carcinoma cell line, MCF-7 cells and negligibly cytotoxic to non-cancerous cell line HEK-293 T cells. The compound exhibited mild cytotoxic activity against A-431 and U-251 cells. The compound also induced ROS generation and mitochondrial depolarization in MCF-7 cells when assessed via the NBT and JC-1 assays, respectively. This is the first report on the production of nonacosenoic acid from the endophytic fungus Chaetomium nigricolor and the assessment of its bioactivity. The isolation, structure elucidation and cytotoxic potential of a fungal fatty acid, Nonacosenoic acid has been reported. [ABSTRACT FROM AUTHOR]

Endophytic fungi reside within plant tissues throughout their entire or partial life cycle, establishing a mutually beneficial symbiotic relationship with their host plant, free from causing any adverse effects or diseases. In addition, endophytic fungi are known as a rich source of new and physiologically active natural chemicals with great therapeutic potentials. Endophytic fungi can promote their host's growth and improve tolerance towards biotic and abiotic stresses. The endophytic fungi associated with mangoes have been infrequently studied, and most isolates lack both morphological characteristics and phylogenetic analyses. When investigating fungal endophytes associated with mango, we isolated four species of Chaetomium from fresh mango leaves, which were collected from mango trees under commercial cultivation in Honghe Prefecture, Yunnan Province, China. Based on morphological comparisons and the results of phylogenetic analyses of concatenated LSU, ITS, rpb2, and tub2 sequence data, here we introduce a new species: Chaetomium hongheensis (KUNCC22-10764, 22-10750); and two new host records: C. cochliodes (KUNCC22-10741) and C. globosum (KUNCC22-10752) from mango leaves. The two new host records were frequently reported on various substrates in China previously. In addition, the new host and country record Chaetomium unguicola (KUNCC22-10758) is first reported in this study as a mango endophyte in China. [ABSTRACT FROM AUTHOR]

Histone acetylation modifications in filamentous fungi play a crucial role in epigenetic gene regulation and are closely linked to the transcription of secondary metabolite (SM) biosynthetic gene clusters (BGCs). Histone deacetylases (HDACs) play a pivotal role in determining the extent of histone acetylation modifications and act as triggers for the expression activity of target BGCs. The genus Chaetomium is widely recognized as a rich source of novel and bioactive SMs. Deletion of a class I HDAC gene of Chaetomium olivaceum SD-80A, g7489, induces a substantial pleiotropic effect on the expression of SM BGCs. The C. olivaceum SD-80A ∆g7489 strain exhibited significant changes in morphology, sporulation ability, and secondary metabolic profile, resulting in the emergence of new compound peaks. Notably, three polyketides (A1–A3) and one asterriquinone (A4) were isolated from this mutant strain. Furthermore, our study explored the BGCs of A1–A4, confirming the function of two polyketide synthases (PKSs). Collectively, our findings highlight the promising potential of molecular epigenetic approaches for the elucidation of novel active compounds and their biosynthetic elements in Chaetomium species. This finding holds great significance for the exploration and utilization of Chaetomium resources. Key points: • Deletion of a class I histone deacetylase activated secondary metabolite gene clusters. • Three polyketides and one asterriquinone were isolated from HDAC deleted strain. • Two different PKSs were reported in C. olivaceum SD-80A. [ABSTRACT FROM AUTHOR]

Premna serratifolia Linn, a medicinally prominent plant is widely used in Ayruvedic, Siddha and Homeopathy medicinal treatments. In this study, out of its leaf fungal endophytes, about 68 Chaetomium sp. exhibited highest percentage similarity to the nearest genera (98.6 %) and thus were evaluated for its therapeutic properties. Chaetomium ethyl acetate extract contained flavonoids and phenolic compounds exhibited promising antioxidant activity against the 2,2-diphenyl-1-picrylhydrazyl radical. Chaetomium ethyl acetate extract induced cytotoxicity to MDA-MB-231, human breast cancer cells. Maximum cytotoxic activity and cell death was obtained with half maximal effective concentration of 96.82±5.23 µg upon exposure for 48 h. Apoptosis with chromatin condensation was visualized with acridine orange and propidium iodide dual staining at these conditions. It could stimulate cancerous MDA-MB-231 cells to undergo apoptosis (60.24 %) as evidenced by flow cytometer analysis mediated through elevated levels of reactive oxygen species (7.5 folds). Such excess reactive oxygen species generation resulted structural injury of the mitochondrial membrane its dissipation of membrane potential as identified by shift from red to green fluorescence of 5,5,6,6'-tetrachloro-1,1',3,3' tetraethylbenzimi-dazoylcarbocyanine iodide dye. One of the bioactive bestowing therapeutic potential was identified as chrysin, a flavone, by high performance liquid chromatography analysis of the extract against the standard chrysin (Rt, 24.68 min). Thus, an effective MDA-MB-231 apoptotic event by the extract is reported. [ABSTRACT FROM AUTHOR]

Armochaetoglasins L (1) and M (2), two new cytochalasans, were isolated from the EtOAc extract of an arthropod-derived fungus Chaetomium globosum. Armochaetoglasin L (1) is a rare 19,20-seco-chaetoglobosin. Their structures were elucidated by NMR spectroscopy and comparison of their electronic circular dichroism (ECD) data. Compounds 1 and 2 were evaluated for anti-inflammatory activity against the NO production by using LPS-stimulated murine macrophage RAW264.7 cells and antibacterial activity against three drug-resistant microbial pathogens. [ABSTRACT FROM AUTHOR]

New technological approaches harness the potential of endophytic fungi as growth promoters, utilizing their bioactive compounds to protect against herbivores, insects, and various unfavourable abiotic stresses, including temperature, salinity, drought, and heavy metals. Zea mays (L.) is considered as a staple food source in many countries including South Africa. Endophytic fungi are natural growth promoters without causing any disease or symptoms of diseases. In the current study, nine endophytic fungi were examined for abiotic stress tolerance and were inoculated in the maize seeds prior to plantation. The construction of the phylogenetic tree was based on consensus sequences (ITS) using endophytic fungi produced three clades with four subgroups. Among the 9 endophytic fungi, only 3 fungal isolates (END 15, MHE 55, RNK 4) grew on 3% and 6% salinity PDA. Boeremia exigua was the only isolate that could withstand 6%. Fusarium solani (MHE 55) survived at low pH. Furthermore, Neurospora sp. (GG 9) and Fusarium solani (MHE 55) grew at 37 °C. Greenhouse experiments were conducted to establish the growth promoting properties. The highest plant height was observed in the treatment which was inoculated with Fusarium oxysporum (GG 8) followed by Fusarium solani (MHE 55), reaching 46 cm and 44 cm respectively. The significant enhancement in plant height, root weight, fresh weight and leaf size, demonstrate the potential use of the selected isolate as a growth promoter for maize. In contrast Chaetomium (PG 9) and Alternaria (MHE 68) displayed none to limited growth promoting properties. To the best of our knowledge, this is the first report on the potential use of F. solani isolated from South African geranium as a growth promoter. As the world is aiming at a more sustainable and eco-friendly agriculture, the use of such endophytes will contribute to better crop production and protection, hence more food availability. [ABSTRACT FROM AUTHOR]

• Biostimulants T. harzianum, C. gloubosum protected tomato plants against early blight disease caused by Alternaria alternata. • Soil application of biostimulants reduced disease incidence and severity. • Treatments enhanced the photosynthetic pigments, NPK uptake and tomato growth attributes. • All stress hallmarks H2O2, electrolyte leakage and MDA were reduced. • The plant defense enzymes peroxidases (POX) and polyphenoloxidase (PPO) activities were improved. Early blight disease caused by Alternaria alternata severely affects tomato growth and productivity. Therefore, to substantiate the increasing demand for tomato fruits, it is essential to explore new strategies to combat the negative effects of the disease. The objectives of this study were to (1) evaluate the effectiveness of Trichoderma harzianum and Chaetomium globosum on disease suppression, (2) determine the influence of the biostimulants on tomato physiological and biochemical traits, and (3) assess the plant innate defense response. In pot experiment, fungal agents were applied to tomato-challenged plants as soil drenches in 8 different treatments. Results revealed that all inoculated plants (T3, T4, T5) exhibited a substantial reduction of disease incidence and severity reached 34 %, 35 %, 26 % and 31 %, 31 %, 16 % respectively compared to infected plants (T2). Such disease stress tolerance was correlated with a significant escalation of tomato growth attributes i.e. plant length, plant FW and DW. The obtained results were consolidated with a noticeable enhancement of the photosynthetic pigments (chlorophyll a, b, and carotenoids) as well as the nitrogen, phosphorus, and potassium (NPK) uptake. Furthermore, a significant reduction in cell stress markers like hydrogen peroxide (H 2 O 2) production, membrane ion leakage and lipid peroxidation (MDA) was detected. Moreover, all enhancements of tomato physiological traits were significantly concurred with up-regulation of plant defense enzymes like peroxidase (POX), polyphenol oxidase (PPO), superoxide dismutase (SOD) and catalase (CAT) 24 h post inoculation reached 3.4, 1.3 1.2, 1.2 folds respectively. Furthermore, both biostimulants were examined for extracellular indole-3-acetic acid (IAA) production. T. harzianum expressed a significant ability for IAA production over C. globosum. Remarkably, the biostimulants consortium showed a significant ability to protect tomato plants. Hence, application of the biostimulants could be a feasible approach for achieving early blight disease resistance. [ABSTRACT FROM AUTHOR]

The chemical engineering of natural extracts has emerged as an effective strategy for the production of diverse libraries of chemicals, making it integral to drug discovery. A chemical engineering strategy based on the epoxidation and ring-opening reactions was used to prepare diversity-enhanced extracts of Chaetomium madrasense 375. Eleven unnatural cytochalasan derivatives (1-11) with unique functional groups, such as amine and isoxazole, were isolated and characterized from these chemically engineered extracts of C. madrasense 375. The identification of these new structures was accomplished through comprehensive spectroscopic analysis, supplemented by synthetic considerations. Notably, compounds 5 and 13-16 displayed potent phytotoxic effects on Arabidopsis thaliana, while compounds 1, 2, 5, 10, and 12 demonstrated inhibitory activities on LPS-induced NO production in RAW264.7 cells. Among them, compound 1 was found to be able to inhibit the upregulated expression of the inducible nitric oxide synthase (iNOS) protein induced by LPS, while also decreasing the production of pro-inflammatory cytokines (IL-6) and influencing the phosphorylation of p38, ERK1/2, and JNK at 100 μM. Our findings demonstrate that the chemical engineering of natural product extracts can be an efficient technique for the generation of novel bioactive molecules. [ABSTRACT FROM AUTHOR]

The association of endophytic fungi with plants was recorded from an early stage of evolution. Endophytic fungi of medicinally important plants are given importance as they mimic the synthesis of bioactive compounds by the host plant. Chromolaena odorata is a wild medicinal plant used in ethnomedicine by different communities. From the root part of C. odorata, an endophytic fungus, Chaetomium sp. R1C1, was isolated, and its biological activities were evaluated. The ITS-rDNA gene sequencing of Chaetomium sp. R1C1 showed 99.21% similarity with Chaetomium globosum. Chaetomium sp. R1C1 was found to secrete protease, amylase, lipase, and cellulose and also produce ammonia. The isolate shows strong antifungal activities against all the nine tested phytopathogens, with the highest inhibition against U. virens (97.45%), followed by A. flavus (94.70%), C. lunata (89.09%), A. brassicicola (78.41%), F. oxysporum (77.71%), R. solani (70.27%), C. capsici (64.41%), A. niger (57.06%), and A. alternata (45.35%). The antibacterial activity evaluated using the agar-well diffusion method and 96-well microtitre method shows that the crude extract was more efficient against gram-negative bacteria, with the highest activity against S. typhi. The DPPH radical scavenging activity shows inhibition of 60.18% and an IC50 value of 85.88 µg/mL, which makes it a strong antioxidant. GC-MS and LC-MS are powerful tools employed to reveal the compounds present in the secondary metabolite of Chaetomium sp. R1C1. This study highlights the importance and applications of the endophytic fungus Chaetomium sp. R1C1 in the fields of agriculture, medicine, and industries. [ABSTRACT FROM AUTHOR]

Biological methods present a sustainable approach for treating various waste polymers due to green, low-cost, mild condition and simple operation. This study, a novel biological method to process nitrocellulose (NC) to obtain NC with low nitrogen via nitrate ester removal using fungal Chaetomium elatum is proposed. The N% of NC continuously declined during the course of six days, from 13.06% to 11.71%, and the intensity of its energetic groups (O-NO2, -NO2) also weakened. An examination of the thermal properties of NC revealed that the weight-loss ratio decreased after biotreatment from 86.33% (untreated NC) to 66.20% (treated NC).Furthermore, the kinetic parameters of the thermal decomposition reaction with DSC were calculated and the activation energy (Ea) of biotreated NC was higher than that of the original, indicating the thermal stability was enhanced. Hence, this structure exploration and thermal analysis provide new methods for further investigating the mechanism of the biological denitrification process and assessing the safety of biotreated NC. [ABSTRACT FROM AUTHOR]

Chaetomium subaffine LB‐1 is a biocontrol strain screened by our laboratory. Mycolytic effect and its action mechanism was researched in this study with Botrytis cinerea and Alternaria solani as test phytopathogenic fungi. Microscopic observation found that hyphae of the test fungi exhibited vacuolated and flocculent when cultured in LB‐1 culture filtrate for 48 h. Physio‐biochemical detection indicated that hyphae of the test fungi displayed red fluorescence with propidium iodide (PI) staining when cultured in LB‐1 culture filtrate 24 h later; conductivity and the leakage value of the extracellular fluid of the test fungi were significantly higher (p ≤.05) than corresponding control fluid of test fungi cultured in potato dextrose broth (PDB), but the malondialdehyde (MDA) contents in hyphae of the test fungi have not significant difference (p ≤.05) between treatment and control. Colorimetric determination showed that the activities of alkaline protease, neutral protease, acidic protease and β‐l,3‐glucanase in LB‐1 culture filtrate were significant. In RNA‐seq analysis, 3644 differentially expressed genes (DEGs) were found in 6 days shaking‐cultured LB‐1 as compared to that of 0 days shaking‐cultured, of which 1756 were up‐regulated and 1888 were down‐regulated. In significantly up‐regulated DEGs, 12 were annotated as cell wall hydrolase, 13 as enzyme of antibiotic substance production and 18 as membrane transporter. The above results indicated that C. subaffine LB‐1 might exert mycolytic effect through altering the permeability of cell membrane and the integrity of cell wall of phytopathogenic fungi, and this altering effect was closely related with cell wall hydrolase, antifungal substance and membrane transporter. [ABSTRACT FROM AUTHOR]

The present study aimed to identify fungal species, specifically Chaetomium bostrychodes and Neoscytalidium novaehollandiae, isolated from seeds of five wheat cultivars: Mahmoudia (MHD), Babil (BBL), Bohooth (BTH), Adena (ADN), and Wefia (WAF). Phenotypic identification of both fungi was conducted based on morphological and microscopic characteristics. Molecular diagnosis, employing internal transcribed spacer primers (ITS1 and ITS4), was utilized to ascertain the species' identity. The morphometric and microscopic results for both fungi demonstrated a consistent agreement with previously published findings related to fungal features. Molecular sequences further confirmed the identity of these species, with a sequence similarity percentage of 90% for C. bostrychodes (KP216865.1 deposited at https://www.ncbi.nlm.nih.gov/genbank/) and 98% for N. novaehollandiae (MT397136.1). Notably, this study marks the first documentation of C. bostrychodes and N. novaehollandiae as wheat seed-borne fungi in Iraq. The molecular confirmation adds a robust layer to the identification process, providing a comprehensive understanding of the fungal species present in the examined wheat cultivars. This novel report contributes valuable insights into the fungal diversity associated with wheat seeds in the region. [ABSTRACT FROM AUTHOR]

The antimicrobial resistance of pathogenic microorganisms against commercial drugs has become a major problem worldwide. This study is the first of its kind to be carried out in Egypt to produce antimicrobial pharmaceuticals from isolated native taxa of the fungal Chaetomium, followed by a chemical investigation of the existing bioactive metabolites. Here, of the 155 clinical specimens in total, 100 pathogenic microbial isolates were found to be multi-drug resistant (MDR) bacteria. The Chaetomium isolates were recovered from different soil samples, and wild host plants collected from Egypt showed strong inhibitory activity against MDR isolates. Chaetomium isolates displayed broad-spectrum antimicrobial activity against C. albicans, Gram-positive, and Gram-negative bacteria, with inhibition zones of 11.3 to 25.6 mm, 10.4 to 26.0 mm, and 10.5 to 26.5 mm, respectively. As a consecutive result, the minimum inhibitory concentration (MIC) values of Chaetomium isolates ranged from 3.9 to 62.5 µg/mL. Liquid chromatography combined with tandem mass spectrometry (LC-MS/MS) analysis was performed for selected Chaetomium isolates with the most promising antimicrobial potential against MDR bacteria. The LC-MS/MS analysis of Chaetomium species isolated from cultivated soil at Assuit Governate, Upper Egypt (3), and the host plant Zygophyllum album grown in Wadi El-Arbaein, Saint Katherine, South Sinai (5), revealed the presence of alkaloids as the predominant bioactive metabolites. Most detected bioactive metabolites previously displayed antimicrobial activity, confirming the antibacterial potential of selected isolates. Therefore, the Chaetomium isolates recovered from harsh habitats in Egypt are rich sources of antimicrobial metabolites, which will be a possible solution to the multi-drug resistant bacteria tragedy. [ABSTRACT FROM AUTHOR]

کوه‌های شهیون و سالندکوه (دزفول، خوزستان)، کبیرکوه (آبدانان، ایلام) و ززوماهرو (الیگودرز، لرستان) بخش‌های بسیار کوچکی از جنگل‌های زاگرس در ایران را تشکیل می‌دهند. در فاصله سال‌های 1400-1398، تعداد 50 نمونه بیمار از درختان جنگلی شامل زالزالک، افرا، بلوط، بنه، بادام کوهی و کنار دارای علائم سوختگی برگ‌، لکه‌برگی، پوسیدگی میوه، خشکیدگی، زوال و مرگ سرشاخه‌ها جمع آوری گردید. تعداد 153 جدایه قارچی روی محیط کشت سیب‌زمینی-دکستروز-آگار (PDA) بدست آمد که 17 جدایه از آن‌ها بر اساس تلفیق ویژگی‌های ریخت‌شناختی و توالی ژن‌های نشانگر مورد شناسایی قرار گرفتند. ویژگی‌های ریخت‌شناختی و شاخص‌های رشدی جدایه‌ها روی محیط‌های کشت آرد یولاف-آگار (OA) و PDA بررسی شدند. ناحیه ITS-rDNA (در بعضی جدایه‌ها) و بخش‌هایی از ژن‌های tub2 (تمام جدایه‌ها) و rpb2 (در بعضی جدایه‌ها) تکثیر و توالی‌یابی شدند. توالی‌های به دست آمده با استفاده از الگوریتم جستجوی بلاست در بانک داده‌های ژنی NCBI مقایسه شدند و تجزیه و تحلیل تبارشناختی آنها بر اساس یک یا چند ناحیه ژنی انجام گرفت. بر اساس نتایج حاصله در تحقیق حاضر، گونه‌های Chaetomium anastomosans، C. ascotrichoides، C. subglobosum، Didymella pomorum، D. prolaticolla و Paramicrosphaeropsis iranica از میزبان­های دارای علایم بیماری شناسایی شدند. با توجه به منابع موجود، این اولین گزارش از گونه‌های C. anastomosans، C. subglobosum و D. prolaticolla برای میکوبیوتای ایران است. همچنین، میزبان‌های جدیدی برای گونه‌های C. anastomosans (بنه، بلوط و زالزالک)، C. ascotrichoides (افرا)، C. subglobosum (بلوط) و P. iranica (بادام کوهی و بنه) گزارش شد.

This article, published in Chemistry of Natural Compounds, discusses the secondary metabolites of Chaetomium angustispirale, a fungus with over 400 species. The study focuses on the extraction and isolation of compounds from the fermented extract of C. angustispirale. Six compounds were identified, including orsellinic acid, orsellide A, shanorellin, adenosine, cochliodinol, and ergosterol. These compounds have novel chemical structures and exhibit significant biological activities, making them valuable resources for drug development. The research was funded by various organizations in Henan Province, China. [Extracted from the article]

Background: Endophytic fungi have proven to be a rich source of novel natural products with a wide-array of biological activities and higher levels of structural diversity. Results: Chemical investigation on the liquid- and solid-state fermented products of Chaetomium globosum Km1226 isolated from the littoral medicinal herb Atriplex maximowicziana Makino resulted in the isolation of compounds 1–14. Their structures were determined by spectroscopic analysis as three previously undescribed C13-polyketides, namely aureonitol C (1), mollipilins G (2), and H (3), along with eleven known compounds 4–14. Among these, mollipilin A (5) exhibited significant nitric oxide production inhibitory activity in LPS-induced BV-2 microglial cells with an IC50 value of 0.7 ± 0.1 µM, and chaetoglobosin D (10) displayed potent anti-angiogenesis property in human endothelial progenitor cells (EPCs) with an IC50 value of 0.8 ± 0.3 µM. Conclusions: Three previously unreported compounds 1–3 were isolated and identified. Mollipilin A (5) and chaetoglobosin D (10) could possibly be developed as anti-inflammatory and anti-angiogenic lead drugs, respectively. [ABSTRACT FROM AUTHOR]

The eukaryotic guided entry of tail-anchored proteins (GET) pathway mediates the biogenesis of tail-anchored (TA) membrane proteins at the endoplasmic reticulum. In the cytosol, the Get3 chaperone captures the TA protein substrate and delivers it to the Get1/Get2 membrane protein complex (GET insertase), which then inserts the substrate via a membrane-embedded hydrophilic groove. Here, we present structures, atomistic simulations and functional data of human and Chaetomium thermophilum Get1/Get2/Get3. The core fold of the GET insertase is conserved throughout eukaryotes, whilst thinning of the lipid bilayer occurs in the vicinity of the hydrophilic groove to presumably lower the energetic barrier of membrane insertion. We show that the gating interaction between Get2 helix α3' and Get3 drives conformational changes in both Get3 and the Get1/Get2 membrane heterotetramer. Thus, we provide a framework to understand the conformational plasticity of the GET insertase and how it remodels its membrane environment to promote substrate insertion. Tail-anchored (TA) membrane protein biogenesis is mediated by the GET insertase. Here, authors present cryo-EM and X-ray structures, MD simulations and functional data for human and fungal insertases showing membrane remodeling for TA insertion. [ABSTRACT FROM AUTHOR]

Chaetomium globosum Kunze, an internationally recognized biocontrol fungus. It mycoparasitizes various plant pathogens and produce antifungal metabolites to suppress the growth of pathogenic fungi. Lack of detailed genome level diversity studies has delimited the development and utilization of potential C. globosum strains. The present study was taken to reveal the distribution, identification, and characterization of expressed sequence tag-simple sequence repeats (EST-SSRs) in C. globosum. RNA-Seq experiment was performed for C. globosum potential isolate Cg2 (AY429049) using Illumina HiSeq 2500. Reference-guided de novo assembly yielded 45,582 transcripts containing 27,957 unigenes. We generated a new set of 8485 EST-SSR markers distributed in 5908 unigene sequences with one SSR locus distribution density per 6.1 kb. Six distinct classes of SSR repeat motifs were identified. The most abundant were mononucleotide repeats (51.67%), followed by tri-nucleotides (36.61%). Out of 5034 EST-SSR primers, 50 primer pairs were selected and validated for the polymorphic study of 15 C. globosum isolates. Twenty-two SSR markers showed average genetic polymorphism among C. globosum isolates. The number of alleles (Na) per marker ranges from 2 to 4, with a total of 74 alleles detected for 22 markers with a mean polymorphism information content (PIC) value of 0.4. UPGMA hierarchical clustering analysis generated three main clusters of C. globosum isolates and exhibited a lower similarity index range from 0.59 to 0.85. Thus, the newly developed EST-SSR markers could replace traditional methods for determining diversity. The study will also enhance the genomic research in C. globosum to explore its biocontrol potential against phytopathogens. [ABSTRACT FROM AUTHOR]

Two novel chlorinated and nitrogenated azaphilones, namely N-butyl-2-aza-2-deoxychaetoviridin A (1) and N-hexyl-2-aza-2-deoxychaetoviridin A (2), along with a previously identified analogue, chaetoviridin A (3), were successfully obtained from Chaetomium globosum 2020HZ23, a marine algal-sourced endophytic fungus. The planar structures as well as the absolute configurations of these new metabolites were determined utilizing a synergistic approach that involved both spectroscopic techniques (1D/2D NMR and HRESIMS) and Density Functional Theory (DFT) calculations. Each compound was subject to in vitro cytotoxicity evaluation toward the A549 cancer cell line. Both compounds 1 and 2 demonstrated significant cytotoxicity, as evidenced by their respective IC50 values of 13.6 and 17.5 μM. Furthermore, 1 and 2 demonstrated potent cell migration inhibition, which elevated with increasing dose concentration. In contrast, compound 3 exhibited less cytotoxic activity relative to 1 and 2, suggesting that the cytotoxic potency escalates with N-substitution at the C-2 position and the introduction of a side chain. This finding could offer implications for future studies aimed at designing and refining lead compounds within this class. [ABSTRACT FROM AUTHOR]

Bioconsortia, based on Chaetomium globosum (isolate CgCG-2), Pseudomonas putida (PpTS-1), Bacillus subtilis (BsS2BC-1), and Trichoderma harzianum (ThS17TH), were designed to develop eco-friendly alternatives for biocontrol of vascular wilt of tomato caused by Fusarium oxysporum f. sp. lycopersici (Fol). In vitro compatibilities of microbes in these consortia were assessed for growth, antagonism, and biocontrol-related gene expression. In these bioassays, the biocontrol isolates had positive interactions for the tested parameters. In pot experiments, seed and soil applications of culture suspensions of five different isolate mixtures were assessed, in comparisons with individual isolates, for efficacy in vascular wilt control after challenge inoculations with Fol under polyhouse conditions. Compared to experimental controls, the biocontrol isolate mixtures reduced vascular wilt incidence and promoted plant growth. PpTS-1 + CgCG-2 + ThS17TH was the most effective microbial consortium, giving 71% reduction of Fusarium wilt incidence compared to non-treated controls. This reduced incidence increased plant growth by 135%. Upregulation of genes encoding for allene oxide cyclase, pathogenesis-related proteins 3, and 5, and β-1,3-glucanase in tomato plants indicated that the reduction in vascular wilt by the consortia could be partly plant-mediated. This study provides new insights into the development of microbial-based consortia for the biocontrol of vascular wilt in tomato. [ABSTRACT FROM AUTHOR]

DEAH‐box helicases play a crucial role in pre‐mRNA splicing as they are responsible for major rearrangements of the spliceosome and are involved in various quality‐ensuring steps. Prp16 is the driving force during spliceosomal catalysis, remodeling the C state into the C* state. Here, the first crystal structure of Prp16 from Chaetomium thermophilum in complex with ADP is reported at 1.9 Å resolution. Comparison with the other spliceosomal DEAH‐box helicases Prp2, Prp22 and Prp43 reveals an overall identical domain architecture. The β‐hairpin, which is a structural element of the RecA2 domain, exhibits a unique position, punctuating its flexibility. Analysis of cryo‐EM models of spliceosomal complexes containing Prp16 reveals that these models show Prp16 in its nucleotide‐free state, rendering the model presented here the first structure of Prp16 in complex with a nucleotide. [ABSTRACT FROM AUTHOR]

Apple Valsa canker (AVC) weakens apple trees and significantly reduces apple production in China and other East Asian countries. Thus far, very few AVC-targeting biocontrol resources have been described. Here, we present a thorough description of a fungal isolate (Chaetomium globosum, 61239) that has strong antagonistic action toward the AVC causal agent Cytospora mali. Potato dextrose broth culture filtrate of strain 61239 completely suppressed the mycelial growth of C. mali on potato dextrose agar, and strongly constrained the development of AVC lesions in in vitro infection assays, ultra-performance liquid chromatography (UPLC) and HPLC-MS/MS investigations supported the conclusion that strain 61239 produces chaetoglobosin A, an antimicrobial metabolite that inhibits C. mali. Using genome sequencing, we discovered a gene cluster in strain 61239 that may be responsible for chaetoglobosin A production. Two of the cluster's genes--cheA, a PKS-NRPS hybrid enzyme, and cheB, an enoyl reductase--were individually silenced, which significantly decreased chaetoglobosin A accumulation as well as the strain's antagonistic activity against C. mali. Together, the findings of our investigation illustrate the potential use of Chaetomium globosum for the management of AVC disease and emphasize the significant contribution of chaetoglobosin A to the antagonistic action of strain 61239. [ABSTRACT FROM AUTHOR]

The thermophilic fungus Chaetomium thermophilum has been used extensively for biochemical and high-resolution structural studies of protein complexes. However, subsequent functional analyses of these assemblies have been hindered owing to the lack of genetic tools compatible with this thermophile, which are typically suited to other mesophilic eukaryotic model organisms, in particular the yeast Saccharomyces cerevisiae. Hence, we aimed to find genes from C. thermophilum that are expressed under the control of different sugars and examine their associated 5' untranslated regions as promoters responsible for sugar-regulated gene expression. To identify sugar-regulated promoters in C. thermophilum, we performed comparative xylose- versus glucose-dependent gene expression studies, which uncovered a number of enzymes with induced expression in the presence of xylose but repressed expression in glucose-supplemented media. Subsequently, we cloned the promoters of the two most stringently regulated genes, the xylosidase-like gene (XYL) and xylitol dehydrogenase (XDH), obtained from this genome-wide analysis in front of a thermostable yellow fluorescent protein (YFP) reporter. With this, we demonstrated xylose-dependent YFP expression by both Western blotting and live-cell imaging fluorescence microscopy. Prompted by these results, we expressed the C. thermophilum orthologue of a well-characterized dominant-negative ribosome assembly factor mutant, under the control of the XDH promoter, which allowed us to induce a nuclear export defect on the pre-60S subunit when C. thermophilum cells were grown in xylose- but not glucose-containing medium. Altogether, our study identified xylose-regulatable promoters in C. thermophilum, which might facilitate functional studies of genes of interest in this thermophilic eukaryotic model organism. [ABSTRACT FROM AUTHOR]

Interest in cave fungal diversity is flourishing because it may represent a reservoir of new species and metabolites. However, the mycobiota remains poorly studied in the underground environment, especially in neotropical regions. During surveys that aimed to investigate the fungal diversity in quartzite and limestone caves in the Southern Espinhaço Mountain in Brazil, six Chaetomiaceae isolates were obtained from different cave substrates. Five taxonomical novelties of Chaetomiaceae in Brazilian caves were discovered based on phylogenetic analyses using DNA sequences from the ITS, LSU, TUB, and RPB2 genes. Chaetomium meridionalense, Pseudohumicola alba, and Pseudohumicola lutea are new species found in Gruta da Extração and Gruta Velha Nova caves. Parahumicola is introduced as a new genus representing a novel phylogenetic lineage with unique morphological characteristics in the family Chaetomiaceae. This new monotypic genus is typified by P. guana, which was found in a bat guano sample in the Gruta Monte Cristo cave. Furthermore, this is the first report of Collariella bostrychodes in a neotropical cave. Overall, these findings emphasise that Brazilian caves constitute an untapped source of fungal resources. [ABSTRACT FROM AUTHOR]

Rhizospheric fungi of medicinal plants are important sources for discovering novel and valuable secondary metabolites with potential pharmaceutical applications. In our research, five new dichlororesorcinols (1–5) and five known metabolites (6–10) were separated from the secondary metabolites of Chaetomium sp. SYP-F6997, which was isolated from the rhizospheric soil of Panax notoginseng. The identification of these compounds was confirmed using various spectroscopic techniques including ESI-MS, UV, IR, NMR and ECD analyses. These findings highlight the potential of rhizospheric fungi as a rich source of novel bioactive compounds. In addition, chiral HPLC was used to successfully separate the enantiomers compound 4 and compound 5, and TDDFT-ECD/optical rotation calculations were used to test their absolute configurations. This is the first report of compounds 1–10 from the genus Chaetomium, and the first report of compounds 1–5 and 7 from the family Chaetomiaceae. We proposed plausible biosynthetic pathways for dichlororesorcinols 1–6 based on their analogous carbon skeleton. These findings provide insights into the biosynthesis of these compounds and expand our understanding of the secondary metabolites produced by Chaetomium sp. SYP-F6997. To evaluate their potential as therapeutic agents, we investigated the cytotoxic activity of all the isolated metabolites against cell lines H9, HL-60, K562, THP-1 and CEM using the MTT method. The new compounds 1 and 2 exhibited significant cytotoxic activities against H9 and CEM, with IC50 values lower than 10 µM. To further explore the potential mechanisms of action, we performed molecular docking studies to investigate the interactions between compounds 1 and 2 with the potential target ERK2. Our results demonstrate that the compounds exhibited strong binding abilities and formed H-bond interactions with ERK2, providing support for their potent antitumor activities and promising potential as lead molecules for the development of antitumor therapeutics. [ABSTRACT FROM AUTHOR]

The oxoglutarate dehydrogenase complex (OGDHc) participates in the tricarboxylic acid cycle and, in a multi-step reaction, decarboxylates α-ketoglutarate, transfers succinyl to CoA, and reduces NAD+. Due to its pivotal role in metabolism, OGDHc enzymatic components have been studied in isolation; however, their interactions within the endogenous OGDHc remain elusive. Here, we discern the organization of a thermophilic, eukaryotic, native OGDHc in its active state. By combining biochemical, biophysical, and bioinformatic methods, we resolve its composition, 3D architecture, and molecular function at 3.35 Å resolution. We further report the high-resolution cryo-EM structure of the OGDHc core (E2o), which displays various structural adaptations. These include hydrogen bonding patterns confining interactions of OGDHc participating enzymes (E1o-E2o-E3), electrostatic tunneling that drives inter-subunit communication, and the presence of a flexible subunit (E3BPo), connecting E2o and E3. This multi-scale analysis of a succinyl-CoA-producing native cell extract provides a blueprint for structure-function studies of complex mixtures of medical and biotechnological value. Summary: Multi-scale and integrative structural analyses provide insight into metabolic regulation by the higher-order architecture of the Chaetomium thermophilum oxoglutarate dehydrogenase complex (OGDHc) metabolon. [ABSTRACT FROM AUTHOR]

Nucleotide Sugar Transporters (NSTs) belong to the SLC35 family (human solute carrier) of membrane transport proteins and are crucial components of the glycosylation machinery. NSTs are localized in the ER and Golgi apparatus membranes, where they accumulate nucleotide sugars from the cytosol for subsequent polysaccharide biosynthesis. Loss of NST function impacts the glycosylation of cell surface molecules. Mutations in NSTs cause several developmental disorders, immune disorders, and increased susceptibility to infection. Atomic resolution structures of three NSTs have provided a blueprint for a detailed molecular interpretation of their biochemical properties. In this work, we have identified, cloned, and expressed 18 members of the SLC35 family from various eukaryotic organisms in Saccharomyces cerevisiae. Out of 18 clones, we determined Vrg4 from Chaetomium thermophilum (CtVrg4) is a GDP-mannose transporter with an enhanced melting point temperature (Tm) of 56.9°C, which increases with the addition of substrates, GMP and GDP-mannose. In addition, we report—for the first time—that the CtVrg4 shows an affinity to bind to phosphatidylinositol lipids. [ABSTRACT FROM AUTHOR]

Chaetomium globosum is a common plant endophytic fungi that exhibits great biocontrol potential in plant disease. Fusarium crown rot (FCR) is an important disease in wheat that seriously threatens wheat production worldwide. The control effect of C. globosum against wheat FCR remains unclear. In this study, we introduced an identified C. globosum 12XP1-2-3 and tested its biological control potential against wheat FCR. The hypha and fermentation broth exhibited an antagonistic effect against Fusarium pseudograminearum. Results from indoor experiments showed that C. globosum 12XP1-2-3 might delay the onset of symptoms of brown stem base and significantly reduced the disease index (37.3%). Field trials showed that wheat seeds coated with a spore suspension of 12XP1-2-3 grew better than the control seeds, had control effects of 25.9-73.1% on FCR disease, and increased wheat yield by 3.2-11.9%. Analysis of rhizosphere microorganisms revealed that seeds coated with C. globosum ('Cg' treatment) had a greater effect on fungal rather than on bacterial alpha diversity and may improve the health state of rhizosphere microorganisms, as reflected by the significantly increased fungal Shannon index at Feekes 11 and the increased complexity of the bacterial co-occurrence network but decreased complexity of the fungal network. Moreover, the accumulation of beneficial bacteria such as Bacillus and Rhizobium at Feekes 3, and Sphingomonas at Feekes 7 in the 'Cg' treatment may be the important contributions to healthier wheat growth state, significantly reduced relative abundance of Fusarium at Feekes 11, and reduced occurrence of FCR disease. These results provide a basis for further research on the mechanism of action of C. globosum and its application in the biological control of FCR in the field. [ABSTRACT FROM AUTHOR]

Flavonoids encompass a heterogeneous group of secondary metabolites with exceptional health benefits. Chrysin, a natural dihydroxyflavone, possesses numerous bioactive properties, such as anticancer, antioxidative, antidiabetic, anti-inflammatory, etc. However, using traditional sources of chrysin involves extracting honey from plants, which is non-scalable, unsustainable, and depends on several factors, including geography, climatic conditions, and the season, which limits its production at a larger scale. Recently, microbial production of desirable metabolites has garnered attention due to the cost-effectiveness, easy scale-up, sustainability, and low emission of waste. We previously reported for the first time the chrysin-producing marine endophytic fungus Chaetomium globosum, associated with a marine green alga. To extend our understanding of chrysin biosynthesis in C. globosum, in the present study, we have assessed the presence of flavonoid pathway intermediates in C. globosum extracts using LC-MS/MS. The presence of several key metabolites, such as dihydrokaempferol, chalcone, galangin, baicalein, chrysin, p-Coumaroyl-CoA, and p-Cinnamoyl-CoA, indicates the role of flavonoid biosynthesis machinery in the marine fungus. Further, we have aimed to enhance the production of chrysin with three different strategies: (1) optimizing the fermentation parameters, namely, growth medium, incubation time, pH, and temperature; (2) feeding key flavonoid pathway intermediates, i.e., phenylalanine and cinnamic acid; (3) elicitation with biotic elicitors, such as polysaccharide, yeast extract, and abiotic elicitors that include UV radiation, salinity, and metal stress. The combined effect of the optimized parameters resulted in a 97-fold increase in the chrysin yield, resulting in a fungal cell factory. This work reports the first approach for enhanced production of chrysin and can serve as a template for flavonoid production enhancement using marine endophytic fungi. [ABSTRACT FROM AUTHOR]

The disintegration of cytoplasm-to-vacuole targeting (Cvt) bodies and autophagic bodies in vacuoles is essential to the Cvt pathway and macroautophagy in yeast. Atg15 is a vacuolar lipase required for the degradation of both Cvt and autophagic bodies. However, the molecular mechanism of their degradation by Atg15 remains poorly understood. In a recent study, we showed that recombinant Chaetomium thermophilum Atg15 (CtAtg15) possesses phospholipase activity, and that this activity is significantly elevated by proteolytic cleavage at a site away from the active center. The proteolytic cleavage of CtAtg15 causes a conformational change around the active center, resulting in the active open state. Interestingly, activated CtAtg15 can degrade not only Cvt and autophagic bodies but also organelle membranes. On the basis of these results, we propose an activation mechanism by which Atg15, as an "organellase," functions only in vacuoles. [ABSTRACT FROM AUTHOR]

Glycosylation, especially N-glycosylation, is one of the most common protein modifications, with immense importance at the molecular, cellular, and organismal level. Thus, accurate and reliable N-glycan analysis is essential in many areas of pharmaceutical and food industry, medicine, and science. However, due to the complexity of the cellular glycosylation process, in-depth glycoanalysis is still a highly challenging endeavor. Contamination of samples with oligosaccharide impurities (OSIs), typically linear glucose homo-oligomers, can cause further complications. Due to their physicochemical similarity to N-glycans, OSIs produce potentially overlapping signals, which can remain unnoticed. If recognized, suspected OSI signals are usually excluded in data evaluation. However, in both cases, interpretation of results can be impaired. Alternatively, sample preparation can be repeated to include an OSI removal step from samples. However, this significantly increases sample amount, time, and effort necessary. To overcome these issues, we investigated the option to enzymatically degrade and thereby remove interfering OSIs as a final sample preparation step. Therefore, we screened ten commercially available enzymes concerning their potential to efficiently degrade maltodextrins and dextrans as most frequently found OSIs. Of these enzymes, only dextranase from Chaetomium erraticum and glucoamylase P from Hormoconis resinae enabled a degradation of OSIs within only 30 min that is free of side reactions with N-glycans. Finally, we applied the straightforward enzymatic degradation of OSIs to N-glycan samples derived from different standard glycoproteins and various stem cell lysates. [ABSTRACT FROM AUTHOR]

Endophytic fungi have proved to be a major source of secondary metabolites, wherein the genus Chaetomium has emerged as a source of multifarious bioactive natural compounds belonging to diverse classes such as chaetoglobosins, epipolythiodioxopiperazines, azaphilones, xanthones, anthraquinone, chromones, depsidones, terpenoids, and steroids. The objective of this review is to encapsulate recent findings on various Chaetomium strains, such as C. globosum, C. cupreum, C. elatum, C. subspirale, C. olivaceum, C. indicum, and C. nigricolor known for production of beneficial secondary metabolites, with an insight into their origin and function. A thorough literature survey was conducted for obtaining Chaetomium-derived secondary metabolites, with a scope of future application into drug development efforts. More than 100 secondary metabolites, with various beneficial properties such as antitumor, cytotoxic, antimalarial, and enzyme inhibitory activities, were enlisted. We believe this review will enhance the understanding of beneficial effects conferred by various Chaetomium-derived secondary metabolites and emphasize their potential in serving novel drug development efforts. Key points: • IdentifiedChaetomium-derived metabolites with potential for drug development. • More than 100 beneficial metabolites are enlisted. • Benefits include anti-cancerous, antimalarial, and anti-enzymatic properties. [ABSTRACT FROM AUTHOR]

Aim Simultaneous management of FOL and RKN causing wilt complex in tomato by chaetoglobosin-producing Chaetomium globosum. Methods and results Random survey was carried out to isolate Fusarium and Chaetomium. Twelve Fusarium isolates were characterized, and FOL4 (virulent) was molecularly identified. Wilt complex by FOL, RKN was assessed individually and in combination under greenhouse. RKN (1000 juveniles ml−1) inoculation followed by FOL4 (5 × 105 spores ml−1) accounted for 90% incidence. The chaetoglobosin-producing Chaetomium was isolated, characterized morphologically and molecularly. Among 55 isolates, nine showed >50% inhibition against FOL, and crude culture filtrate showed a significant reduction in RKN egg hatching (15.66%) and juvenile mortality (100%). Chaetomium Cg 40 was confirmed as C. globosum using SCAR marker (OK032373). Among 40 volatile compounds, hexadecanoic acid and 1,2-epoxy-5,9-cyclododecadiene exhibited antifungal and nematicidal properties in GC–MS. High-performance liquid chromatography revealed chaetoglobosin A (0.767 μg μl−1), and the presence of bioactive molecules chaetoglobosin (528.25  m/z), chaetomin (710  m/z), chaetocin (692.8  m/z), chaetoviridin (432.85  m/z), and chaetomugilin (390  m/z) was confirmed by LC/MS/MS. Cg 40 and Cg 6 were able to synthesize the pks1 a, b gene responsible for chaetoglobosin, sporulation, and melanin biosynthesis was confirmed by PCR. The application of an aqueous formulation as seed treatment, seedling dip, and soil drenching (application) recorded lowest wilt incidence (11.11%) and gall index (1) with the maximum growth parameter (plant height 51.9 cm), fruit yield (287.5 g), and lycopene content (11.46 mg/100 g). Conclusions Cg 40 and Cg 6, containing polyketides, secondary metabolites, antibiotics, chaetoglobosin, and plant growth-promoting ability, showed antifungal and nematicidal properties against the FOL–RKN wilt complex in tomato in vitro and pot culture experiments. [ABSTRACT FROM AUTHOR]

This paper presents the effect of water extracts from the leaves of various Mentha spp. on the growth of selected fungi causing the gray decay of wood. The study determined which of the Mentha spp. extracts used had the best effect on inhibiting the development of fungi on various substrates including pine wood. The best results in the complete inhibition of fungi growth on an agar medium were obtained for the M. × piperita 'Almira' extract. Biocidal properties were not achieved on wood samples, although it was noticed that at doses of extracts of 600 g/m2 and higher, the growth of fungi in the initial stages of cultivation was clearly inhibited. Chemical substances in the obtained extracts were characterized by gas chromatography. Oxygen monoterpenes were the dominant group of substances, substances belonging to sesquiterpene hydrocarbons, monoterpene hydrocarbons containing oxygen sesquiterpenes, and one substance belonging to non-terpene hydrocarbons were also identified. [ABSTRACT FROM AUTHOR]

DNA polymerase δ (Pol δ) is a key enzyme for the maintenance of genome integrity in eukaryotic cells, acting in concert with the sliding clamp processivity factor PCNA (proliferating cell nuclear antigen). Three of the four subunits of human Pol δ interact directly with the PCNA homotrimer via a short, conserved protein sequence known as a PCNA interacting protein (PIP) motif. Here, we describe the identification of a PIP motif located towards the N terminus of the PolD4 subunit of Pol δ (equivalent to human p12) from the thermophilic filamentous fungus Chaetomium thermophilum and present the X‐ray crystal structure of the corresponding peptide bound to PCNA at 2.45 Å. Like human p12, the fungal PolD4 PIP motif displays non‐canonical binding to PCNA. However, the structures of the human p12 and fungal PolD4 PIP motif peptides are quite distinct, with the fungal PolD4 PIP motif lacking the 310 helical segment that characterises most previously identified PIP motifs. Instead, the fungal PolD4 PIP motif binds PCNA via conserved glutamine that inserts into the Q‐pocket on the surface of PCNA and with conserved leucine and phenylalanine sidechains forming a compact 2‐fork plug that inserts into the hydrophobic pocket on PCNA. Despite the unusual binding mode of the fungal PolD4, isothermal calorimetry (ITC) measurements show that its affinity for PCNA is similar to that of its human orthologue. These observations add to a growing body of information on how diverse proteins interact with PCNA and highlight how binding modes can vary significantly between orthologous PCNA partner proteins. [ABSTRACT FROM AUTHOR]

Endophytic fungi live in inter-cellular spaces of healthy plant tissues without causing any apparent symptoms of diseases for the host plant. Some fungal endophytes help their plant hosts to survive under biotic and abiotic stresses. In this study, we collected healthy mango leaves at the Honghe mango plantations (Yunnan Province) in the winter. A total of 34 different fungal endophytic strains were isolated, and their phylogenetic placements were estimated based on the ITS gene. Members of genus Chaetomium were the dominant fungal endophytes (26%). Common bacterial plant pathogens (Erwinia amylovora and Pseudomonas syringae) and fungal plant pathogens (Botrytis cinerea and Penicillium digitatum) were selected to test the antagonism of the fungal endophytes isolated from mango leaves through co-cultivation in vitro assay. Three strains of Chaetomium sp. viz. KUNCC22-0749, UNCC22-10750, and KUNCC22-10752 showed great inhibition against two bacterial pathogens viz. Erwinia amylovora and Pseudomonas syringae, and Alternaria sp. KUNCC22-10760, Chaetomium sp. KUNCC22-10749, Daldinia sp. KUNCC22-10744, and Rosellinia sp. KUNCC22-10751 also showed great to moderate antagonistic effects against two fungal pathogens viz. Botrytis cinerea and Penicillium digitatum. [ABSTRACT FROM AUTHOR]

Chaetomium cupreum, a root endophyte in Miscanthus sinensis, enhances Al tolerance in M. sinensis by changing aluminum (Al) localization and the production of a siderophore, oosporein, which chelates Al for detoxification. Oosporein has various functions, including insecticidal activity, phytotoxicity, antifungal activity, and a siderophore. In our study, we focused on the detoxification effect of oosporein as a siderophore and on the growth of M. sinensis under Al exposure. In addition, the phytotoxicity of oosporein to M. sinensis was confirmed to compare with those in Lactuca sativa and Oryza sativa as control plants. Under Al stress, oosporein promoted plant growth in M. sinensis seedlings at 10 ppm, which was the same concentration as that detected in M. sinensis roots infected with C. cupreum in our previous study. Oosporein also showed low phytotoxicity to M. sinensis compared with L. sativa at even high concentrations of oosporein. These results suggest that the concentration of oosporein in M. sinensis roots would be maintained at the appropriate concentration to detoxify Al and would promote M. sinensis growth under Al stress, although oosporein would show low phytotoxicity to the natural host plant, M. sinensis, compared with the non-host plant, L. sativa. [ABSTRACT FROM AUTHOR]

Exonucleases are often found associated with polymerase or helicase domains in the same enzyme or can function as autonomous entities to maintain genome stability. Here, we uncovered Chaetomium thermophilum RecQ family proteins that also have exonuclease activity in addition to their main helicase function. The novel exonuclease activity is separate from the helical core domain and coexists with the latter two enzymatic activities on the same polypeptide. The Ct RecQ121-366 exonuclease region performs independently as an exonuclease. We describe its catalytic mechanism and biological characteristics. We demonstrate unequivocally that Ct RecQ121-366 exclusively displays exonuclease activity and that this activity has a 3′–5′ polarity that can both hydrolyze ssDNA and cleave dsDNA substrates. The hydrolytic activity of majority exonuclease is driven by bimetal ions, and this appears to be the case for the Ct RecQ121-366 exonuclease as well. Additionally, the maximum activity of Ct RecQ121-366 was observed at pH 8.0–9.0, low salt with Mg2+. The two helices in the structure, a6 and a7, play significant roles in the execution by anticipating their shape and changing essential amino acids. • CtRecQ helicase and DNA nuclease activities reside on the same polypeptide. • Ct RecQ121-366 is a 3′-5′exonuclease that can degrade ssDNA. • Ct RecQ121-366 is a 3′-5′exonuclease that can degrade dsDNA. • The maximum activity of Ct RecQ121-366 was observed at pH 8.0–9.0, low salt, Mg2+. • The two helices in the structure of Ct RecQ121-366, a6 and a7, play significant roles. [ABSTRACT FROM AUTHOR]

Chaetoglobosin A (CheA), a well-known macrocyclic alkaloid with prominently highly antimycotic, antiparasitic, and antitumor properties, is mainly produced by Chaetomium globosum. However, a limited understanding of the transcriptional regulation of CheA biosynthesis has hampered its application and commercialization in agriculture and biomedicine. Here, a comprehensive study of the CgXpp1 gene, which encodes a basic helix-loop-helix family regulator with a putative role in the regulation of fungal growth and CheA biosynthesis, was performed by employing CgXpp1-disruption and CgXpp1-complementation strategies in the biocontrol species C. globosum. The results suggest that the CgXpp1 gene could be an indirect negative regulator in CheA production. Interestingly, knockout of CgXpp1 considerably increased the transcription levels of key genes and related regulatory factors associated with the CheA biosynthetic. Disruption of CgXpp1 led to a significant reduction in spore production and attenuation of cell development, which was consistent with metabolome analysis results. Taken together, an in-depth analysis of pleiotropic regulation influenced by transcription factors could provide insights into the unexplored metabolic mechanisms associated with primary and secondary metabolite production. [ABSTRACT FROM AUTHOR]

Dextran problem restricts the development of the sugar industry. Although the enzymatic treatment based on α-dextranase from Chaetomium gracile (α-dextranase (CG)) has been effective in solving this issue, the lack of immobilization products hinder its industrial applications. This research described a novel and suitable method to immobilize α-dextranase (CG). The purified α-dextranase (CG) was immobilized via cross-linking using modified chitosan as carriers. In addition, this study used a deep eutectic solvent that greatly improved the enzymatic properties of immobilized α-dextranase (CG). α-dextranase (CG) was immobilized by adding deep eutectic solvent (DES-IM-α-dextranase (CG)) showed better temperature tolerance and storage properties than free and ordinary immobilized counterparts. It can eliminate dextran by 59.71% in mixed sugarcane juice and 38.71% in clarified sugarcane juice. The achieved results were considerably better than those obtained using free and other immobilized enzymes. Altogether, these findings confirmed that DES-IM-α-dextranase (CG) displayed great potential in solving the dextran problem. [ABSTRACT FROM AUTHOR]

The antimicrobial resistance of pathogenic microorganisms against commercial drugs has become a major problem worldwide. This study is the first of its kind to be carried out in Egypt to produce antimicrobial pharmaceuticals from isolated native taxa of the fungal Chaetomium, followed by a chemical investigation of the existing bioactive metabolites. Here, of the 155 clinical specimens in total, 100 pathogenic microbial isolates were found to be multi-drug resistant (MDR) bacteria. The Chaetomium isolates were recovered from different soil samples, and wild host plants collected from Egypt showed strong inhibitory activity against MDR isolates. Chaetomium isolates displayed broad-spectrum antimicrobial activity against C. albicans, Gram-positive, and Gram-negative bacteria, with inhibition zones of 11.3 to 25.6 mm, 10.4 to 26.0 mm, and 10.5 to 26.5 mm, respectively. As a consecutive result, the minimum inhibitory concentration (MIC) values of Chaetomium isolates ranged from 3.9 to 62.5 µg/mL. Liquid chromatography combined with tandem mass spectrometry (LC-MS/MS) analysis was performed for selected Chaetomium isolates with the most promising antimicrobial potential against MDR bacteria. The LC-MS/MS analysis of Chaetomium species isolated from cultivated soil at Assuit Governate, Upper Egypt (3), and the host plant Zygophyllum album grown in Wadi El-Arbaein, Saint Katherine, South Sinai (5), revealed the presence of alkaloids as the predominant bioactive metabolites. Most detected bioactive metabolites previously displayed antimicrobial activity, confirming the antibacterial potential of selected isolates. Therefore, the Chaetomium isolates recovered from harsh habitats in Egypt are rich sources of antimicrobial metabolites, which will be a possible solution to the multi-drug resistant bacteria tragedy.

The fungal community of biodeteriorated 17th century mural paintings within the nave and altar portion of the old Church of the Holy Ascension (Veliki Krčimir, Nišava District, Serbia) has been studied via an array of microscopic analyses in order to detect actively growing fungi and assess their potential damage to the painted layer and mortar. In situ microscopy, performed with portable microscopes, together with optical and scanning electron microscopy, has revealed impairments of the painted layer in the form of cracks and biopitting, along with surface salt deposits and hidden, symptomless fungal growth. Various structures, such as fully developed fruiting bodies and melanized mycelia, clusters of microcolonial fungi and lichen soredia, as well as a conidial apparatus and numerous conidia in mass have been observed, all attesting to the presence of actively growing fungal community on the surface of the painted layer and in the interspaces between the painted layer and mortar. Based on the observed reproductive structures, the main agents of biodeterioration have been identified as fungi of Chaetomium and Cladosporium genera. The documented deterioration symptoms are most likely due to hyphal penetration and formation of fruiting bodies and other fungal structures.

C. globosum is an endophytic fungus, which is recorded effective against several fungal and bacterial diseases in plants. The exclusively induce defense as mechanism of biocontrol for C. globosum against phytopathogens is reported. Our pervious study states the effectiveness of induced defense by C. globosum (Cg), in tomato against Alternaria solani. In this study the temporal transcriptome analysis of tomato plants after treatment with C. globosum was performed for time points at 0 hpCi, 12 hpCi, 24 hpCi and 96 phCi. The temporal expression analysis of genes belonging to defense signaling pathways indicates the maximum expression of genes at 12 h post Cg inoculation. The sequential progression in JA signaling pathway is marked by upregulation of downstream genes (Solyc10g011660, Solyc01g005440) of JA signaling at 24 hpCi and continued to express at same level upto 96 hpCi. However, the NPR1 (Solyc07g040690), the key regulator of SA signaling is activated at 12 h and repressed in later stages. The sequential expression of phenylpropanoid pathway genes (Solyc09g007920, Solyc12g011330, Solyc05g047530) marks the activation of pathway with course of time after Cg treatment that results in lignin formation. The plant defense signaling progresses in sequential manner with time course after Cg treatment. The results revealed the involvement of signaling pathways of ISR and SAR in systemic resistance induced by Cg in tomato, but with temporal variation. [ABSTRACT FROM AUTHOR]

The antimicrobial activity of endophytic fungi isolated from Euphorbia milii was evaluated against Gram-positive, Gram-negative bacteria, unicellular yeast, and filamentous fungi. Chaetomium ovatoascomatis NRC was identified morphologically and genetically as the most active strain. The total ethyl acetate extract of C. ovatoascomatis NRC demonstrated significant antimicrobial activity against Gram-negative; Escherichia coli, Salmonella enteric, and fungi; Aspergillus niger with MIC of 62.5 ug/ml. Whereas n-hexane fraction demonstrated broader activity against Gram-positive; Bacillus subtilis, Lactobacillus cereus, Gram-negative; Escherichia coli and Salmonella enteric, fungi; Candida albicans and F. solani. LC–MS/MS analysis of ethyl acetate strain extract and GC–MS analysis of the n-hexane fraction were used to identify the metabolites of the strain extract. LC–MS/MS determined three major metabolites with potential antimicrobial activities including grevilline B, aflatoxin G2 and apigenin. GC–MS analysis of n-hexane fraction tentatively identified 30 compounds, where 9,12-octadecadienoic acid methyl ester was the major compound. [ABSTRACT FROM AUTHOR]

Chaetoglobosin A is a complex macrocyclic alkaloid with potent antimycotic, antiparasitic and antitumor properties. However, the low output and high cost of chaetoglobosin A biosynthesis have hampered the application and commercialization of chaetoglobosin A in agriculture and biomedicine. Here, the CgMfs1 gene, which encodes the major facilitator superfamily secondary transporter, was identified based on bioinformatics analysis, and an intensive study of its effects on chaetoglobosin A biosynthesis and secretion was performed using CgMfs1‐silencing and CgMfs1‐overexpression strategies. Inactivation of CgMfs1 caused a notable decrease in chaetoglobosin A yield from 58.66 mg/L to 19.95 mg/L (MFS1–3) and 17.13 mg/L (MFS1–4). The use of an efficient expression plasmid in Chaetomium globosum W7 to generate the overexpression mutant OEX13 resulted in the highest chaetoglobosin A increase to 298.77 mg/L. Interestingly, the transcription level of the polyketide synthase gene significantly fluctuated with the change in CgMfs1, confirming that the predicted efflux gene CgMfs1 could play a crucial role in chaetoglobosin A transportation. Effective efflux of chaetoglobosin A could possibly alleviate feedback inhibition, resulting in notable increase in the expression of the polyketide synthase gene. Furthermore, we utilized cornstalk as the fermentation substrate to produce chaetoglobosin A, and scanning electron microscopy and Fourier transform‐infrared spectroscopy revealed that the strain OEX13 could well degrade cornstalk, presenting significant increases in the chaetoglobosin A yield, when compared with that produced by the wild‐type strain (from 40.32 to 191.90 mg/L). Thus, this research provides a novel analogous engineering strategy for the construction of high‐yielding strain and offers new insight into large‐scale chaetoglobosin A production. [ABSTRACT FROM AUTHOR]