Structure and Function of Bacterial Microbiota in Eucommia ulmoides Bark.

The study aimed to explore the bacterial community composition and the functions of core microbiota in Eucommia ulmoides bark. The bark samples of E. ulmoides were collected from Wangcang Sichuan Province, Cili Hunan Province, and Zunyi Guizhou Province, in China, respectively. Through the high-throughput sequencing methods and techniques, the community composition, core microbiota, and function of the bacteria were studied. The bacterial community of E. ulmoides bark consisted of 9 phyla, 11 classes, 22 orders, 28 families, 31 genera, and 37 OTUs. At the genus level, the dominant genus was the unclassified bacteria of Cyanobacteria, with a relative abundance of 97.01%. The bacterial communities of E. ulmoides bark from different areas have their unique units except for the common microbiota. The core microbiota of bacteria included an unclassified genus of Cyanobacteria, an unclassified genus of Mitochondria, Pseudomonas, Sphingobium, Rhizobium, Novosphingobium, Enterobacter, Rhodococcus, Curtobacterium, and Ralstonia. FAPROTAX function prediction suggested that the core microbiota has a substantial potential for photoautotrophy, phototrophy, aerobic chemoheterotrophy, chemoheterotrophy. Ten taxa composed the core microbiota, and the majority of them were related to the pharmacologically active ingredients of E. ulmoides bark. The research provides a scientific basis for the biological marker of genuineness and microbial technology for improving the content of medicinal ingredients of E. ulmoides.

Radicicol rescues yeast cell death triggered by expression of human α-synuclein and its A53T mutant, but not by human ßA4 peptide and proapoptotic protein bax.

Aggregation/misfolding of α-synuclein and ßA4 proteins cause neuronal cell death (NCD) associated with Parkinson's and Alzheimer's disease. It has been suggested that a heat shock protein-90 (Hsp90) inhibitor can prevent NCD by activating the heat shock transcription factor-1 which, in turn, upregulates molecular chaperones such as Hsp70 that targets aggregated/misfolded proteins for refolding/degradation. We have isolated radicicol, an Hsp90 inhibitor, from a fungus occurring in the crevices of marble rocks of Central India. Radicicol, which was found to be a strong antioxidant, was tested for its ability to rescue yeast cells from death induced by expression of wild-type α-synuclein, its more toxic A53T mutant, and ßA4. It effectively overcomes wild-type/mutant α-synuclein mediated yeast cell death, concomitantly diminishes ROS levels, reverses mitochondrial dysfunction and prevents nuclear DNA-fragmentation, a hallmark of apoptosis. Surprisingly however, radicicol is unable to rescue yeast cells from death triggered by expression of secreted ßA4. Moreover, although radicicol acts as an antioxidant it fails to prevent yeast cell death inflicted by the proapoptotic protein, Bax. Our results indicate that radicicol specifically targets aggregated/misfolded α-synuclein's toxicity and opens up the possibility of using multiple yeast assays to screen natural product libraries for compounds that would unambiguously target α-synuclein aggregation/misfolding.

An Aspergillus aculateus strain was capable of producing agriculturally useful nanoparticles via bioremediation of iron ore tailings.

Mining waste such as iron ore tailing is environmentally hazardous, encouraging researchers to develop effective bioremediation technologies. Among the microbial isolates collected from iron ore tailings, Aspergillus aculeatus (strain T6) showed good leaching efficiency and produced iron-containing nanoparticles under ambient conditions. This strain can convert iron ore tailing waste into agriculturally useful nanoparticles. Fourier-transform Infrared Spectroscopy (FT-IR analysis) established the at the particles are protein coated, with energy dispersive X-ray Spectroscopy (EDX analysis) showing strong signals for iron. Transmission Electron Microscopy (TEM analysis) showed semi-quasi spherical particles having average size of 15 ±â€¯5 nm. These biosynthesized nanoparticles when tested for their efficacy on seed emergence activity of mungbean (Vigna radiata) seeds, and enhanced plant growth at 10 and 20 ppm.

Development of a novel myconanomining approach for the recovery of agriculturally important elements from jarosite waste.

In this study, an ecofriendly and economically viable waste management approach have been attempted towards the biosynthesis of agriculturally important nanoparticles from jarosite waste. Aspergillus terreus strain J4 isolated from jarosite (waste from Debari Zinc Smelter, Udaipur, India), showed good leaching efficiency along with nanoparticles (NPs) formation under ambient conditions. Fourier-transform infrared spectroscopy (FT-IR) and transmission electron microscopy (TEM) confirmed the formation of NPs. Energy dispersive X-ray spectroscopy (EDX analysis) showed strong signals for zinc, iron, calcium and magnesium, with these materials being leached out. TEM analysis and high resolution transmission electron microscopy (HRTEM) showed semi-quasi spherical particles having average size of 10-50nm. Thus, a novel biomethodology was developed using fungal cell-free extract for bioleaching and subsequently nanoconversion of the waste materials into nanostructured form. These biosynthesized nanoparticles were tested for their efficacy on seed emergence activity of wheat (Triticum aestivum) seeds and showed enhanced growth at concentration of 20ppm. These nanomaterials are expected to enhance plant growth properties and being targeted as additives in soil fertility and crop productivity enhancement.

Fungal Endophytes: A Potential Source of Antibacterial Compounds.

Antibiotic resistance is becoming a burning issue due to the frequent use of antibiotics for curing common bacterial infections, indicating that we are running out of effective antibiotics. This has been more obvious during recent corona pandemics. Similarly, enhancement of antimicrobial resistance (AMR) is strengthening the pathogenicity and virulence of infectious microbes. Endophytes have shown expression of various new many bioactive compounds with significant biological activities. Specifically, in endophytic fungi, bioactive metabolites with unique skeletons have been identified which could be helpful in the prevention of increasing antimicrobial resistance. The major classes of metabolites reported include anthraquinone, sesquiterpenoid, chromone, xanthone, phenols, quinones, quinolone, piperazine, coumarins and cyclic peptides. In the present review, we reported 451 bioactive metabolites isolated from various groups of endophytic fungi from January 2015 to April 2021 along with their antibacterial profiling, chemical structures and mode of action. In addition, we also discussed various methods including epigenetic modifications, co-culture, and OSMAC to induce silent gene clusters for the production of noble bioactive compounds in endophytic fungi.

Recent Advances in the Discovery of Antiviral Metabolites from Fungi.

As the world manages the impact of a global pandemic caused by COVID-19, the discovery of new antiviral agents has become way more relevant and urgent. Viruses are submicroscopic infectious agents that replicate inside the living cells of different organisms. These viruses use nucleic acids (both DNA and RNA) for further replication and maturity inside the cells. Some of the viruses responsible for various human and plant diseases belong to the classes of Picornaviridae, Retroviridae, Orthomyxoviridae, Flaviviridae, Pneumoviridae, Virgaviridae, and Hepadnaviridae, and their treatment options are limited or non-existent. The consistent reemergence and resistance development in the viral strains demand the discovery and development of new antiviral drugs possessing better efficacy. Bio-active compounds isolated from fungi can be the source of new compounds with enhanced potency and new mechanisms of action. Fungi are known to produce a diverse lot of secondary metabolites due to their existence in harsh and testing climates which are often inhabitable for many organisms. Because of these unique environments, fungi produce a variety of secondary metabolites of different chemical classes like alkaloids, quinones, furanone, pyrones, benzopyranoids, xanthones, terpenes, steroids, peptides, and many acyclic compounds. Fungal metabolites are known to display a wide range of bioactive attributes, i.e., anticancer, antibacterial, antifungal, and anti-Alzheimer's, along with antiviral properties. In this review article, we report over 300 antiviral compounds from fungal sources during the period of 2009 to 2019. The source of these compounds is marine and endophytic fungi and they are arranged based on their antiviral action against different viral families. These compounds offer promise for their use and development as future antiviral drugs.

Incidence of keratinophilic fungi from the soils of Vedanthangal Water Bird Sanctuary (India).

Fifty-three soil samples were collected from various sites in the vicinity of Vedanthangal Water Bird Sanctuary and screened for the presence of keratinophilic fungi using the hair baiting techniques for isolation. Twenty-eight isolates were recovered and identified by recognition of their macro- and micromorphological features. Seven species related to five genera were recorded viz. Auxarthron conjugatum (1.89%), Chrysosporium fluviale (3.77%), Chrysosporium indicum (20.75%), Chrysosporium tropicum (7.55%), Chrysosporium state of Ctenomyces serratus (5.66%), Gymnoascus petalosporus (1.89%) and Microsporum gypseum complex (11.32%). The study shows that migratory birds harbour a variety of keratinophiles and may be a potential source of transfer of these fungi from one location to another.

Keratinophilic fungi from the feathers of Emu (Dromaius novaehollandiae) in Maharastra India.

A total of 70 feathers samples of Emu (Dromaius novaehollandiae) were collected from 7 Emu farms situated at two districts (Raigad and Thane) of Maharashtra (India) and screened for resident keratinophilic fungi. Among them, 44 isolates were recovered and identified by evaluating characteristic macro- and micro-morphological features. Further gene products corresponding to the ITS1-5.8S-ITS2 rDNA region from all isolates were amplified and sequenced. Homology search was performed using BLAST program against non-redundant nucleotide database, and significantly matched DNA sequences deposited to the NCBI Gene Bank for reference purposes. Eight identified fungal species belongs to 7 different genera named as Aphanoascus terreus Ac_MW577456 (21.43%), Microsporum gypseum Ac_MW580920 (14.29%), Ctenomyces serratus Ac_MW577459 (10.0%), Uncinocarpus orissi Ac_MW577461 (5.17%), Aphanoascus verrucosus Ac_MW577458 (4.29%), Gymnascella dankaliensis Ac_MW577460 (2.86%), Gymnoascoideus petalosporus Ac_MW577462 (2.86%) and Arthroderma tuberculatum Ac_MW577457 (1.43%).

Exophiarin, an isocoumarin from the fungus Exophiala sp. with antihyperglycemic activity.

Chemical characterization of ethyl acetate extract of Exophiala sp. has afforded the isolation of three compounds including a new isocoumarin named exophiarin (1). Exophiala sp. was obtained from the soil containing dumped organic waste (litter). Initially, LC-UV-MS analysis of the extract of Exophiala sp. revealed the presence of a new compound having molecular weight 438 (1) and previously reported TPI-2 and TPI-5. The novelty was established using advanced database search comprising of biological source, molecular weight and UV profile. 1D, 2D NMR and HRMS data have been used for structure elucidation. Exophiarin with TPI-2 and TPI-5 have displayed moderate improvement in glucose uptake activity when tested in rat skeletal muscle cell line L6.

Bacterial Community Analysis and Potential Functions of Core Taxa in Different Parts of the Fungus Cantharellus cibarius.

Cantharellus cibarius is a widely distributed, popular, edible fungus with high nutritional and economic value. However, significant challenges persist in the microbial ecology and artificial cultivation of C. cibarius. Based on the 16S rRNA sequencing data, this study analyzed bacterial community structures and diversity of fruit bodies and rhizomorph parts of C. cibarius and mycosphere samples (collected in the Wudang District, Guiyang, Guizhou Province, China). It explored the composition and function of the core bacterial taxa. The analyzed results showed that the rhizomorph bacterial community structure was similar to mycosphere, but differed from the fruit bodies. Members of the Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium complex had the highest abundance in the fruit bodies. However, they were either absent or low in abundance in the rhizomorphs and mycosphere. At the same time, members of the Burkholderia-Caballeronia-Paraburkholderia complex were abundant in the fruit bodies and rhizomorphs parts of C. cibarius, as well as mycosphere. Through functional annotation of core bacterial taxa, we found that there was an apparent trend of potential functional differentiation of related bacterial communities in the fruit body and rhizomorph: potential functional groups of core bacterial taxa in the fruit bodies centered on nitrogen fixation, nitrogen metabolism, and degradation of aromatic compounds, while those in rhizomorphs focused on aerobic chemoheterotrophy, chemoheterotrophy, defense against soil pathogens, decomposition of complex organic compounds, and uptake of insoluble inorganic compounds. The analysis of functional groups of bacteria with different structures is of great significance to understand that bacteria promote the growth and development of C. cibarius.

Phylogeny and taxonomy of two new Plectosphaerella (Plectosphaerellaceae, Glomerellales) species from China.

The genus Plectosphaerella is the largest genus in the family Plectosphaerellaceae. Some species are plant pathogens, whereas others are soil-borne. Seven Plectosphaerella isolates were collected from various locations in the southwest of China. Using multi-locus phylogenetic (LSU, ITS, EF1α, RPB2) analyses combined with morphological characteristics, two new species, Plectosphaerella guizhouensis sp. nov. and Plectosphaerella nauculaspora sp. nov. are described, illustrated and compared with related species.

Mangrove-Associated Fungi: A Novel Source of Potential Anticancer Compounds.

Cancer is the second leading cause of death worldwide, and the number of cases is increasing alarmingly every year. Current research focuses on the development of novel chemotherapeutic drugs derived from natural as well as synthetic sources. The abundance and diversity in natural resources offer tremendous potential for the discovery of novel molecules with unique mechanisms for cancer therapy. Mangrove-derived fungi are rich source of novel metabolites, comprising novel structure classes with diverse biological activities. Across the globe, coastal areas are primarily dominated by mangrove forests, which offer an intensely complex environment and species that mostly remain unexplored. In recent years, many structurally diverse compounds with unique skeletons have been identified from mangrove fungi and evaluated for their antiproliferative properties. These compounds may serve as lead molecules for the development of new anticancer drugs. Mangrove endophytes can be modulated using epigenetic means or culture optimization methods to improve the yield or to produce various similar analogs. The present review provides an insight into the bioactive metabolites from mangrove endophytes reported during the period from 2012 to 2018 (up to April, 2018) along with their cytotoxic properties, focusing on their chemical structures and mode of action, as indicated in the literature.

Endophytic Fungi: A Source of Potential Antifungal Compounds.

The emerging and reemerging forms of fungal infections encountered in the course of allogeneic bone marrow transplantations, cancer therapy, and organ transplants have necessitated the discovery of antifungal compounds with enhanced efficacy and better compatibility. A very limited number of antifungal compounds are in practice against the various forms of topical and systemic fungal infections. The trends of new antifungals being introduced into the market have remained insignificant while resistance towards the introduced drug has apparently increased, specifically in patients undergoing long-term treatment. Considering the immense potential of natural microbial products for the isolation and screening of novel antibiotics for different pharmaceutical applications as an alternative source has remained largely unexplored. Endophytes are one such microbial community that resides inside all plants without showing any symptoms with the promise of producing diverse bioactive molecules and novel metabolites which have application in medicine, agriculture, and industrial set ups. This review substantially covers the antifungal compounds, including volatile organic compounds, isolated from fungal endophytes of medicinal plants during 2013⁻2018. Some of the methods for the activation of silent biosynthetic genes are also covered. As such, the compounds described here possess diverse configurations which can be a step towards the development of new antifungal agents directly or precursor molecules after the required modification.

Marine Fungi: A Source of Potential Anticancer Compounds.

Metabolites from marine fungi have hogged the limelight in drug discovery because of their promise as therapeutic agents. A number of metabolites related to marine fungi have been discovered from various sources which are known to possess a range of activities as antibacterial, antiviral and anticancer agents. Although, over a thousand marine fungi based metabolites have already been reported, none of them have reached the market yet which could partly be related to non-comprehensive screening approaches and lack of sustained lead optimization. The origin of these marine fungal metabolites is varied as their habitats have been reported from various sources such as sponge, algae, mangrove derived fungi, and fungi from bottom sediments. The importance of these natural compounds is based on their cytotoxicity and related activities that emanate from the diversity in their chemical structures and functional groups present on them. This review covers the majority of anticancer compounds isolated from marine fungi during 2012-2016 against specific cancer cell lines.

Nonribosomal Peptides from Marine Microbes and Their Antimicrobial and Anticancer Potential.

Marine environments are largely unexplored and can be a source of new molecules for the treatment of many diseases such as malaria, cancer, tuberculosis, HIV etc. The Marine environment is one of the untapped bioresource of getting pharmacologically active nonribosomal peptides (NRPs). Bioprospecting of marine microbes have achieved many remarkable milestones in pharmaceutics. Till date, more than 50% of drugs which are in clinical use belong to the nonribosomal peptide or mixed polyketide-nonribosomal peptide families of natural products isolated from marine bacteria, cyanobacteria and fungi. In recent years large numbers of nonribosomal have been discovered from marine microbes using multi-disciplinary approaches. The present review covers the NRPs discovered from marine microbes and their pharmacological potential along with role of genomics, proteomics and bioinformatics in discovery and development of nonribosomal peptides drugs.

The Pharmacological Potential of Non-ribosomal Peptides from Marine Sponge and Tunicates.

Marine biodiversity is recognized by a wide and unique array of fascinating structures. The complex associations of marine microorganisms, especially with sponges, bryozoans, and tunicates, make it extremely difficult to define the biosynthetic source of marine natural products or to deduce their ecological significance. Marine sponges and tunicates are important source of novel compounds for drug discovery and development. Majority of these compounds are nitrogen containing and belong to non-ribosomal peptide (NRPs) or mixed polyketide-NRP natural products. Several of these peptides are currently under trial for developing new drugs against various disease areas, including inflammatory, cancer, neurodegenerative disorders, and infectious disease. This review features pharmacologically active NRPs from marine sponge and tunicates based on their biological activities.

Endophytic fungi: a reservoir of antibacterials.

Multidrug drug resistant bacteria are becoming increasingly problematic particularly in the under developed countries of the world. The most important microorganisms that have seen a geometric rise in numbers are Methicillin resistant Staphylococcus aureus, Vancomycin resistant Enterococcus faecium, Penicillin resistant Streptococcus pneumonia and multiple drug resistant tubercule bacteria to name a just few. New drug scaffolds are essential to tackle this every increasing problem. These scaffolds can be sourced from nature itself. Endophytic fungi are an important reservoir of therapeutically active compounds. This review attempts to present some data relevant to the problem. New, very specific and effective antibiotics are needed but also at an affordable price! A Herculean task for researchers all over the world! In the Asian subcontinent indigenous therapeutics that has been practiced over the centuries such as Ayurveda have been effective as "handed down data" in family generations. May need a second, third and more "in-depth investigations?"