Search Results (6)

Bacterial strain TSO55 was isolated from a commercial field of wheat (Triticum turgidum L. subsp. durum), under organic amendments, located in the Yaqui Valley, Mexico. Morphological and microscopical characterization showed off-white irregular colonies and Gram-positive bacillus, respectively. The draft genome sequence of this strain revealed a genomic size of 5,489,151 bp, with a G + C content of 35.21%, N50 value of 245,934 bp, L50 value of 8, and 85 contigs. Taxonomic affiliation showed that strain TSO55 belongs to Bacillus paranthracis, reported as an emergent human pathogen. Genome annotation identified 5743 and 5587 coding DNA sequences (CDSs), respectively, highlighting genes associated with indole production, phosphate and potassium solubilization, and iron acquisition. Further in silico analysis indicated the presence of three CDSs related to pathogenicity islands and a high pathogenic potential (77%), as well as the presence of multiple gene clusters related to antibiotic resistance. The in vitro evaluation of plant growth promotion traits was negative for indole production and phosphate and potassium solubilization, and it was positive but low (18%) for siderophore production. The biosynthetic gene cluster for bacillibactin (siderophore) biosynthesis was confirmed. Antifungal bioactivity of strain TSO55 evaluated against wheat pathogenic fungi (Alternaria alternata TF17, Bipolaris sorokiniana TPQ3, and Fusarium incarnatum TF14) showed minimal fungal inhibition. An antibiotic susceptibility assay indicated resistance to three of the six antibiotics evaluated, up to a concentration of 20 µg/mL. The beta hemolysis result on blood agar reinforced TSO55’s pathogenic potential. Inoculation of B. paranthracis TSO55 on wheat seedlings resulted in a significant decrease in root length (−8.4%), total plant height (−4.2%), root dry weight (−18.6%), stem dry weight (−11.1%), and total plant dry weight (−15.2%) compared to the control (uninoculated) treatment. This work highlights the importance of analyzing the microbiological safety of organic amendments before application. Comprehensive genome-based taxonomic affiliation and bioprospecting of microbial species introduced to the soil by organic agricultural practices and any microbial inoculant will prevent the introduction of dangerous species with non-beneficial traits for crops, which affect sustainability and generate potential health risks for plants and humans. Full article

The exploration of new pharmacological compounds from endophytic fungi offers infinite possibilities. The aim of this study was to evaluate the antibacterial and antioxidant activities of extracts from the leaves of Ziziphus lotus and five of its endophytic fungi and investigate the chemical diversity of the secondary metabolites produced. Isolated, purified, and molecularly identified endophytes and plant leaves were subjected to ethyl acetate extraction. The antibacterial potential of the extracts was assessed by the disc diffusion method against five bacterial strains: Staphylococcus aureus ATCC 25923; Staphylococcus aureus MU50; Enterococcus faecalis WDCM00009; Escherichia coli ATCC 25922; and Pseudomonas aeruginosa ATCC 27853. DPPH and reducing power tests were performed to assess antioxidant potential. GC–MS analysis was used to identify volatile compounds in extracts. Fungal endophytes were identified as Aspergillus cavernicola, Aspergillus persii, Alternaria alternata, Cladosporium asperlatum, and Fusarium incarnatum–equiseti complex, with respective accession numbers DTO 412-G6, DTO 412-I5, DTO 413-E7, DTO 412-G4, and DTO 414-I2. GC–MS analysis revealed a large number of bioactive compounds. All extracts showed antibacterial activity against at least two of the bacteria tested, and most showed antioxidant activity. The Aspergillus cavernicola extract stood out for its higher phenolic content and higher antioxidant and antibacterial activities in all tests. Full article

Popular edible mushrooms Ganoderma lucidum and Gloeostereum incarnatum can improve physical health as a prebiotic and positively alter intestinal microbiota. Our research investigated the prebiotic effects of Ganoderma lucidum and Gloeostereum incarnatum on colon inflammation through G. lucidum water extraction polysaccharides (GLP), G. incarnatum water extraction polysaccharides (GIP), G. lucidum ethanol extraction (GLE), and G. incarnatum ethanol extraction (GIE) administered in mice after 7 days of dextran sulphate sodium (DSS) administration. Among the extracts, GLE showed reduced mortality rates, prevention of weight loss, mitigated colon length shortening, and decreased disease activity indices and histological scores. COX-2, MPO, and iNOS activities and the inflammatory cytokines’ expressions were determined to demonstrate the inhibition inflammation by GLE. Meanwhile, GLE upregulated the levels of MUC2, ZO-1, claudin-3, and occluding to protect the intestinal barrier. Furthermore, GLE modulated the composition of gut microbiota disturbed by DSS, as it decreased the abundance of Bacteroides, Staphylococcus, and Escherichia_Shigella, and increased Turicibacter and Bifidobacterium. Through cell experiment, GLE had a positive influence on adherens junction, tight junction, and TRAF6/MyD88/NF-κB signaling pathways. In conclusion, GLE supplementation promotes DSS-induced colitis recovery by regulating inflammatory cytokines, preserving the intestinal mucosal barrier, positively modulating microbiota changes, and positively influences immune response in TRAF6/MyD88/NF-κB signaling pathways. Full article

Malaysia has begun to locally mass-cultivate grain corn to reduce import dependency for animal feed industries. Since the Malaysian tropical climate constantly exposes grain corn to fungal colonization and mycotoxin production by mycotoxigenic species, it is, therefore, important to investigate the presence of fungal species, especially the mycotoxigenic strains in the Malaysian grain corn agroecosystem. In the present work, corn kernel, tassel, plant debris, and soil were collected from two pioneer grain corn farms (Kampong Dadong, KD; Rhu Tapai, RT), and morphological and molecular identifications were conducted. A total of 131 fungal isolates from 30 fungal species were recovered. Both KD and RT yielded log 4.7–6.7 CFU/g total fungal loads. Fusarium verticillioides was predominant in both farms, followed by the phytopathogenic Lasiodiplodia theobromae and the mycotoxigenic Aspergillus flavus, A. niger, F. incarnatum, and F. proliferatum. Mycotoxin analyses by high-performance liquid chromatography revealed that among 30 mycotoxigenic isolates tested for aflatoxins, deoxynivalenol, fumonisins, HT-2, T-2, ochratoxins A, and zearalenone, approximately 25 of the isolates could produce at least one mycotoxin in vitro. The present work serves as a baseline for more comprehensive research to better predict and control fungal contamination and the subsequent mycotoxin accumulation in Malaysian grain corn agroecosystems. Full article

Crimson clover (Trifolium incarnatum L.) is the most common legume cover crop in the United States. Previous research found limited genetic variation for crimson clover within the National Plant Germplasm System (NPGS) collection. The aim of this study was to assess the phenotypic and nodule microbial diversity within the NPGS crimson clover collection, focusing on traits important for cover crop performance. Experiments were conducted at the Beltsville Agricultural Research Center (Maryland, USA) across three growing seasons (2012–2013, 2013–2014, 2014–2015) to evaluate 37 crimson clover accessions for six phenotypic traits: fall emergence, winter survival, flowering time, biomass per plant, nitrogen (N) content in aboveground biomass, and proportion of plant N from biological nitrogen fixation (BNF). Accession effect was significant across all six traits. Fall emergence of plant introductions (PIs) ranged from 16.0% to 70.5%, winter survival ranged from 52.8% to 82.0%, and growing degree days (GDD) to 25% maturity ranged from 1470 GDD to 1910 GDD. Biomass per plant ranged from 1.52 to 6.51 g, N content ranged from 1.87% to 2.24%, and proportion of plant N from BNF ranged from 50.2% to 85.6%. Accessions showed particularly clear differences for fall emergence and flowering time, indicating greater diversity and potential for selection in cover crop breeding programs. Fall emergence and winter survival were positively correlated, and both were negatively correlated with biomass per plant and plant N from BNF. A few promising lines performed well across multiple key traits, and are of particular interest as parents in future breeding efforts, including PIs 369045, 418900, 561943, 561944, and 655006. In 2014–2015, accessions were also assessed for nodule microbiome diversity, and 11 genera were identified across the sampled nodules. There was large variation among accessions in terms of species diversity, but this diversity was not associated with observed plant traits, and the functional implications of nodule microbiome diversity remain unclear. Full article

Gloeostereum incarnatum is a precious edible mushroom that is widely grown in Asia and known for its useful medicinal properties. Here, we present a high-quality genome of G. incarnatum using the single-molecule real-time (SMRT) sequencing platform. The G. incarnatum genome, which is the first complete genome to be sequenced in the family Cyphellaceae, was 38.67 Mbp, with an N50 of 3.5 Mbp, encoding 15,251 proteins. Based on our phylogenetic analysis, the Cyphellaceae diverged ~174 million years ago. Several genes and gene clusters associated with lignocellulose degradation, secondary metabolites, and polysaccharide biosynthesis were identified in G. incarnatum, and compared with other medicinal mushrooms. In particular, we identified two terpenoid-associated gene clusters, each containing a gene encoding a sesterterpenoid synthase adjacent to a gene encoding a cytochrome P450 enzyme. These clusters might participate in the biosynthesis of incarnal, a known bioactive sesterterpenoid produced by G. incarnatum. Through a transcriptomic analysis comparing the G. incarnatum mycelium and fruiting body, we also demonstrated that the genes associated with terpenoid biosynthesis were generally upregulated in the mycelium, while those associated with polysaccharide biosynthesis were generally upregulated in the fruiting body. This study provides insights into the genetic basis of the medicinal properties of G. incarnatum, laying a framework for future characterization of bioactive proteins and pharmaceutical uses of this fungus. Full article