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Microorganisms Feb 2022Few data exist on the human gut mycobiome in relation to lifestyle, ethnicity, and dietary habits. To understand the effect of these factors on the structure of the...
Mycobiome-Host Coevolution? The Mycobiome of Ancestral Human Populations Seems to Be Different and Less Diverse Than Those of Extant Native and Urban-Industrialized Populations.
Few data exist on the human gut mycobiome in relation to lifestyle, ethnicity, and dietary habits. To understand the effect of these factors on the structure of the human gut mycobiome, we analyzed sequences belonging to two extinct pre-Columbian cultures inhabiting Puerto Rico (the Huecoid and Saladoid) and compared them to coprolite samples found in Mexico and Ötzi, the Iceman's large intestine. Stool mycobiome samples from extant populations in Peru and urban cultures from the United States were also included. The ancient Puerto Rican cultures exhibited a lower fungal diversity in comparison to the extant populations. Dissimilarity distances showed that the Huecoid gut mycobiome resembled that from ancient Mexico. Fungal genera including spp., spp., spp., spp., spp., spp., spp., and spp. were differentially abundant in the ancient and extant populations. Despite cultural differences, certain fungal taxa were present in all samples. These results suggest that culture and diet may impact the gut mycobiome and emphasize that modern lifestyles could be associated with the alteration of gut mycobiome diversity. The present study presents data on ancient and extant human gut mycobiomes in terms of lifestyle, ethnicity, and diet in the Americas.
PubMed: 35208912
DOI: 10.3390/microorganisms10020459 -
Current Biology : CB Mar 2022The horizontal transfer of large gene clusters by mobile elements is a key driver of prokaryotic adaptation in response to environmental stresses. Eukaryotic microbes...
The horizontal transfer of large gene clusters by mobile elements is a key driver of prokaryotic adaptation in response to environmental stresses. Eukaryotic microbes face similar stresses; however, a parallel role for mobile elements has not been established. A stress faced by many microorganisms is toxic metal ions in their environment. In fungi, identified mechanisms for protection against metals generally rely on genes that are dispersed within an organism's genome. Here, we discover a large (∼85 kb) region that confers tolerance to five metal/metalloid ions (arsenate, cadmium, copper, lead, and zinc) in the genomes of some, but not all, strains of a fungus, Paecilomyces variotii. We name this region HEPHAESTUS (Hφ) and present evidence that it is mobile within the P. variotii genome with features characteristic of a transposable element. HEPHAESTUS contains the greatest complement of host-beneficial genes carried by a transposable element in eukaryotes, suggesting that eukaryotic transposable elements might play a role analogous to bacteria in the horizontal transfer of large regions of host-beneficial DNA. Genes within HEPHAESTUS responsible for individual metal tolerances include those encoding a P-type ATPase transporter-PcaA-required for cadmium and lead tolerance, a transporter-ZrcA-providing tolerance to zinc, and a multicopper oxidase-McoA-conferring tolerance to copper. In addition, a subregion of Hφ confers tolerance to arsenate. The genome sequences of other fungi in the Eurotiales contain further examples of HEPHAESTUS, suggesting that it is responsible for independently assembling tolerance to a diverse array of ions, including chromium, mercury, and sodium.
Topics: Byssochlamys; Cadmium; Copper; DNA Transposable Elements; Zinc
PubMed: 35063120
DOI: 10.1016/j.cub.2021.12.048 -
Frontiers in Microbiology 2021Polymicrobial co-fermentation is among the distinct character of high-temperature Daqu. However, fungal communities in the three types of high-temperature Daqu, namely,...
Polymicrobial co-fermentation is among the distinct character of high-temperature Daqu. However, fungal communities in the three types of high-temperature Daqu, namely, white high-temperature Daqu, black high-temperature Daqu, and yellow high-temperature Daqu, are yet to be characterized. In this study, the fungal diversity, taste, and aroma profiles in the three types of high-temperature Daqu were investigated by Illumina MiSeq high-throughput sequencing, electronic tongue, and electronic nose, respectively. Ascomycota and Basidiomycota were detected as the absolute dominant fungal phylum in all types of high-temperature Daqu samples, whereas , , , , , and were identified as the dominant fungal genera. The fungal communities of the three types of high-temperature Daqu differed significantly ( < 0.05), and , , and could serve as the biomarkers in white high-temperature Daqu, black high-temperature Daqu, and yellow high-temperature Daqu, respectively. The three types of high-temperature Daqu had an extremely significant difference ( < 0.01) in flavor: white high-temperature Daqu was characterized by sourness, bitterness, astringency, richness, methane, alcohols, ketones, nitrogen oxides, and sulfur organic compounds; black high-temperature Daqu was characterized by aftertaste-A, aftertaste-B, methane-aliph, hydrogen, and aromatic compounds; and yellow high-temperature Daqu was characterized by saltiness, umami, methane, alcohols, ketones, nitrogen oxides, and sulfur organic compounds. The fungal communities in the three types of high-temperature Daqu were significantly correlated with taste but not with aroma, and the aroma of high-temperature Daqu was mainly influenced by the dominant fungal genera including , , , and . The result of the present study enriched and refined our knowledge of high-temperature Daqu, which had positive implications for the development of traditional brewing technique.
PubMed: 34925290
DOI: 10.3389/fmicb.2021.784651 -
Allergy Mar 2022
Topics: Allergens; Byssochlamys; Humans; Paecilomyces
PubMed: 34773271
DOI: 10.1111/all.15176 -
Frontiers in Plant Science 2021Biochar has been reported to play a positive role in disease suppression against airborne pathogens in plants. The mechanisms behind this positive trait are not...
Biochar has been reported to play a positive role in disease suppression against airborne pathogens in plants. The mechanisms behind this positive trait are not well-understood. In this study, we hypothesized that the attraction of plant growth-promoting rhizobacteria (PGPR) or fungi (PGPF) underlies the mechanism of biochar in plant protection. The attraction of PGPR and PGPF may either activate the innate immune system of plants or help the plants with nutrient uptake. We studied the effect of biochar in peat substrate (PS) on the susceptibility of strawberry, both on leaves and fruits, against the airborne fungal pathogen . Biochar had a positive impact on the resistance of strawberry fruits but not the plant leaves. On leaves, the infection was more severe compared with plants without biochar in the PS. The different effects on fruits and plant leaves may indicate a trade-off between plant parts. Future studies should focus on monitoring gene expression and metabolites of strawberry fruits to investigate this potential trade-off effect. A change in the microbial community in the rhizosphere was also observed, with increased fungal diversity and higher abundances of amplicon sequence variants classified into , , and surrounding the plant root, where the latter two were reported as biocontrol agents. The change in the microbial community was not correlated with a change in nutrient uptake by the plant in either the leaves or the fruits. A decrease in the defense gene expression in the leaves was observed. In conclusion, the decreased infection of in strawberry fruits mediated by the addition of biochar in the PS is most likely regulated by the changes in the microbial community.
PubMed: 34497619
DOI: 10.3389/fpls.2021.700479 -
Scientific Reports Aug 2021Paecilomyces variotii xylanase was, produced in stirred tank bioreactor with yield of 760 U/mL and purified using 70% ammonium sulfate precipitation and ultra-filtration...
Paecilomyces variotii xylanase was, produced in stirred tank bioreactor with yield of 760 U/mL and purified using 70% ammonium sulfate precipitation and ultra-filtration causing 3.29-fold purification with 34.47% activity recovery. The enzyme purity was analyzed on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) confirming its monomeric nature as single band at 32 KDa. Zymography showed xylan hydrolysis activity at the same band. The purified enzyme had optimum activity at 60 °C and pH 5.0. The pH stability range was 5-9 and the temperature stability was up 70 °C. Feand Fe exhibited inhibition of xylanase enzyme while Cu, Ca, Mg and Mn stimulated its activity. Mercaptoethanol stimulated its activity; however, Na-EDTA and SDS inhibited its activity. The purified xylanase could hydrolyze beechwood xylan but not carboxymethyl cellulose (CMC), avicel or soluble starch. Paecilomyces variotii xylanase K and V for beechwood were determined to be 3.33 mg/mL and 5555 U/mg, respectively. The produced xylanase enzyme applied on beech xylan resulted in different types of XOS. The antioxidant activity of xylo-oligosaccharides increased from 15.22 to 70.57% when the extract concentration was increased from 0.1 to 1.5 mg/mL. The enzyme characteristics and kinetic parameters indicated its high efficiency in the hydrolysis of xylan and its potential effectiveness in lignocellulosic hydrolysis and other industrial application. It also suggests the potential of xylanase enzyme for production of XOS from biomass which are useful in food and pharmaceutical industries.
Topics: Antioxidants; Bioreactors; Byssochlamys; Electrophoresis, Polyacrylamide Gel; Endo-1,4-beta Xylanases; Glucuronates; Hydrogen-Ion Concentration; Oligosaccharides
PubMed: 34389757
DOI: 10.1038/s41598-021-95965-w -
Frontiers in Microbiology 2021Wheat-originated microbes play an important role in shaping the quality of high-temperature which is commonly used as a starter for producing sauce-flavor . However,...
Wheat-originated microbes play an important role in shaping the quality of high-temperature which is commonly used as a starter for producing sauce-flavor . However, the shifts of microbiota from raw material to fresh and then to mature remain unclear. Hence, in the present study, the inner and outer of fresh and mature were collected to explore the correlation between microbiota and metabolites as well as the source of the microbiota in . Results indicated that the activities of amylase and protease between the inner and outer of fresh varied significantly while both parts became similar after maturation. The predominant bacteria shifted from (outer) and (inner) to (both outer and inner), while the predominant fungi shifted from (both outer and inner) to (outer) and (inner). A combining analysis of headspace solid-phase micro extraction-gas chromatography-mass spectrometry, headspace gas chromatography-ion mobility spectrometry, and nuclear magnetic resonance was employed to detect the metabolites. The network analysis was conducted to perform the relationships between microbes and metabolites. The results showed that the bacteria, especially , , and , had a strong correlation with the productions of esters, amino acids and their derivatives, and sugars and their derivatives, while most fungi such as , were negatively correlated with the phenylalanine, trimethylamine n-oxide, and isovalerate. SourceTracker analysis indicated that wheat was the important source of the microbiota, especially, the microorganisms in the inner of might be the drivers of the microbial succession during maturation. This study provided a comprehensive exploration to understand the microbial sources and shifts in high-temperature during maturation.
PubMed: 34322112
DOI: 10.3389/fmicb.2021.714726 -
Journal of Fungi (Basel, Switzerland) May 2021Two novel xylanolytic enzymes, a xylanase and a β-xylosidase, were simultaneously isolated and characterized from the extracellular medium of ATHUM 8891 (anamorph...
Two novel xylanolytic enzymes, a xylanase and a β-xylosidase, were simultaneously isolated and characterized from the extracellular medium of ATHUM 8891 (anamorph ATHUM 8891), grown on Brewer's Spent Grain as a sole carbon source. They represent the first pair of characterized xylanolytic enzymes of the genus and the first extensively characterized xylanolytic enzymes of the family . In contrast to other xylanolytic enzymes isolated from the same family, both enzymes are characterized by exceptional thermostability and stability at low pH values, in addition to activity optima at temperatures around 65 °C and acidic pH values. Applying nano-LC-ESI-MS/MS analysis of the purified SDS-PAGE bands, we sequenced fragments of both proteins. Based on sequence-comparison methods, both proteins appeared conserved within the genus . Xylanase was classified within Glycoside Hydrolase family 11 (GH 11), while β-xylosidase in Glycoside Hydrolase family 3 (GH 3). The two enzymes showed a synergistic action against xylan by rapidly transforming almost 40% of birchwood xylan to xylose. The biochemical profile of both enzymes renders them an efficient set of biocatalysts for the hydrolysis of xylan in demanding biorefinery applications.
PubMed: 34072339
DOI: 10.3390/jof7060430 -
Plants (Basel, Switzerland) Apr 2021Hydroponic systems have gained interest and are increasingly used in hot and dry desert areas. Numbers of benefits are offered by hydroponic systems such as the ability...
Hydroponic systems have gained interest and are increasingly used in hot and dry desert areas. Numbers of benefits are offered by hydroponic systems such as the ability to save water, enhance nutrients use efficiency, easy environmental control, and prevention of soil-borne diseases. However, the high consumption of chemical fertilizers for nutrient solution and the sensitivity of closed hydroponic systems to salinity are issues that need solutions. Thus, the main goal of our research activities is to isolate plant growth promoting fungi in order to develop sustainable hydroponic systems. We are working on isolating and testing the possibility to incorporate the cell-free filtrate (CFF) of plant growth promoting fungi (PGPF) in the composition of the nutrient solution. In this work, we isolated six strains of PGPF from the rhizosphere of the halophyte grass . Phylogenetic analyses of DNA sequences amplified by ITS1 and ITS4 primers identified the isolated fungi as: , , , , , and . The promoting of vigor in tobacco seedlings was used as criteria to evaluate the biostimulant activity of these fungi by adding either their mycelia (DE: direct effect) or their cell-free filtrates (CFF: indirect effect) to the plant-growth media. The best significant growth stimulation was obtained with plants treated by . However, only the CFFs of (A5.1) and (A8) when added at a dilution factor of 1/50 to half-strength nutritive solution (0.5NS) resulted in significant improvement of all assessed growth parameters. Indeed, the A5.1CFF and A8CFF in 0.5NS induced a significant better increase in the biomass production when compared to NS or 0.5NS alone. All fungi produced indole acetic acid in the CFFs, which could be one of the key factors explaining their biostimulant activities. Furthermore, six genes involved in nitrogen-metabolism ( and ), auxin biosynthesis ( and ), and brassinosteroid biosynthesis ( and ) were shown to be induced in roots or leaves following treatment of plants with the all CFFs. This work opens up a prospect to study in deep the biostimulant activity of PGPFs and their applications to decrease the requirement of chemical fertilizers in the hydroponic growing systems.
PubMed: 33923476
DOI: 10.3390/plants10040784 -
Frontiers in Microbiology 2020Lipopeptide biosurfactants produced by sp. were assessed regarding their antimicrobial activity against foodborne pathogenic and food spoilage microorganisms. Both...
Lipopeptide biosurfactants produced by sp. were assessed regarding their antimicrobial activity against foodborne pathogenic and food spoilage microorganisms. Both Gram-positive and Gram-negative bacteria were found not to be susceptible to these lipopeptides. However, mycosubtilin and mycosubtilin/surfactin mixtures were very active against the filamentous fungi and , with minimum inhibitory concentrations (MICs) of 1-16 mg/L. They were also active against , MIC = 16-64 mg/L. Moreover it was found that the antifungal activity of these lipopeptides was not affected by differences in isoform composition and/or purity. Furthermore their cytotoxicity tested on two different cell lines mimicking ingestion and detoxification was comparable to those of approved food preservatives such as nisin. Overall, for the first time here mycosubtilin and mycosubtilin/surfactin mixtures were found to have high antifungal activity against food relevant fungi at concentrations lower than their toxicity level hence, suggesting their application for extending the shelf-life of products susceptible to these moulds. In addition combining nisin with mycosubtilin or mycosubtiliin/surfactin mixtures proved to be an effective approach to produce antimicrobials with broader spectrum of action.
PubMed: 33505362
DOI: 10.3389/fmicb.2020.561060