The hygrophorones, a class of cyclopentenones isolated from fruiting bodies of the genus Hygrophorus (basidiomycetes), show promising antifungal activity. While the constitution of ...4,6-diacetylhygrophorone A super(12) (3) and the relative configuration of the stereogenic centers in the cyclopentenone ring were elucidated using standard NMR and MS techniques, the relative configuration of the exocyclic stereogenic center could not be assigned. By introducing a sample of 3 into an alignment medium and measuring anisotropic NMR parameters, namely, residual dipolar couplings, we were able to unambiguously determine the relative configuration of all three stereogenic centers in 4,6-diacetylhygrophorone A super(12) simultaneously by fitting several structure proposals to the experimental data.
Nemania aenea SF 10099-1, a basidiomycete isolated from a forest soil sample, regio- and stereoselectively epoxidized beta -caryophyllene (Car) to (-)- beta -caryophyllene oxide (Car-Ox) in a ...liquid-liquid interface bioreactor (L-L IBR) consisted of a liquid medium (a bottom phase), a fungus-ballooned microsphere (MS) mat (a middle phase), and an organic phase containing Car (a top phase). The cultivation conditions, such as carbon and nitrogen sources, kind of MS, initial medium pH and Car concentration, were optimized in the L-L IBR system. The best carbon and nitrogen sources were xylose and tryptone, respectively. The most suitable polyacrylonitrile MS was MMF-DE-1 (former MFL-80SDE; non-coated type). Although the strain could not grow below pH 5.5, the endocyclic epoxidation of Car efficiently proceeded at a wide range of initial medium pH (6.0 to 9.0). The bioconversion system exhibited an excellent alleviation effect toward substrate and product inhibitions. While Car could be added into an organic phase (KF-96L-1CS, dimethyl silicone oil) at 50% (w/v), the accumulation of Car-Ox reached over 30 g/l in spite of these strong microbial toxicities. Moreover, the epoxidation reaction smoothly proceeded in a novel L-L IBR system, a multistory L-L IBR systems, consisted of 5 stacked reactor units. The optical rotation of Car-Ox produced was (-) and the enantiomeric excesses of (-)- beta -Car-Ox purified by 1st and 2nd recrystallization from methanol reached 97.51 and 99.33%, respectively.
Understanding the origin and evolution of pathogenicity and biotrophic life-style of rust fungi has remained a conundrum for decades. Research on the molecular mechanisms responsible for rust fungi ...evolution has been hampered by their biotrophic life-style until the sequencing of some rust fungi genomes. With the availability of multiple whole genomes and EST data for this group, it is now possible to employ genome-wide surveys and investigate how natural selection shaped their evolution. In this work, we employed a phylogenomics approach to search for positive selection and genes undergoing accelerated evolution at the origin of rust fungi on an assembly of single copy genes conserved across a broad range of basidiomycetes. Up to 985 genes were screened for positive selection on the phylogenetic branch leading to rusts, revealing a pervasive signal of positive selection throughout the data set with the proportion of positively selected genes ranging between 19.6-33.3%. Additionally, 30 genes were found to be under accelerated evolution at the origin of rust fungi, probably due to a mixture of positive selection and relaxation of purifying selection. Functional annotation of the positively selected genes revealed an enrichment in genes involved in the biosynthesis of secondary metabolites and several metabolism and transporter classes.
DESTRUCTION OF XENOBIOTICS BY CULTURE FILTRATE FROM XYLOTROPHIC BASIDIOMYCETES Fedotov, O. V., Donetsk National University, Vinnitsa. o.fedotov@donnu.edu.ua; Klimenko, S. Yu
Biolohichnyĭ visnyk Melitopolʹsʹkoho derz͡h︡avnoho pedahohichnoho universytetu imeni Bohdana Khmelʹnyt͡s︡koho,
11/2015, Volume:
5, Issue:
3
Journal Article
Peer reviewed
Open access
The article deals with the efficiency of pollutants biodegradation by xylotrophic basidiomycetes submerged cultures grown on standard glucose-peptone medium (GPM). The efficiency of pollutants ...biodegradation was determined by the model compound – dye Methyl Orange. The purpose of the work is screening of 19 species 81 strains xylotrophic basidiomycetes cultures on the indicator of the dye oxidative degradation efficiency and exploring the possibility of induction of this indicator by modifying the culture medium. The biodegradation efficiency was determined by following method. Assigned amount of culture filtrate (experiment) or medium (control) was added to the 0.001% solution of Methyl Orange in sodium acetate buffer. pH of the reaction mixture was 4.4 units. Samples were incubated at +40°C for 48 hours. Then pH of the reaction mixture was set up at 3.1 units using sodium acetate buffer and the optical density of solutions at a wavelength of 506 nm was measured. The efficiency of biodegradation was calculated by the difference of the optical density of control and experiment as a percentage. The most promising strains – F. velutipes F-1105, P. eryngii P-er, T. hirsuta Th-11 and D. quercina Dq-08 were selected. The composition of the glucose-peptone medium was modified for these strains by the introduction in the medium lignosulfonate, Tween 80, Kirk’s minerals solution and selecting the concentration of these components. According to the study for the purpose of pollutants degradation it is advisable to cultivate F. velutipes F-1105 strain on modified GPM, which further comprises at 1 l: lignosulfonate – 3.5 g; Tween 80 – 1.0 g, Kirk’s minerals solution – 70 ml; P. eryngii P-er strain – 5.0 g, 1.0 g, 70 ml; T. hirsuta Th-11 strain – 5.0 g, 1.0 g, 105 ml; and D. quercina Dq-08 strain – 6.5 g, 1.0 g, 105 ml, respectively. This allowed to increase the model compound degradation efficiency by the culture filtrate of strain F. velutipes F-1105 in 9,3; D. quercina Dq-08 – in 9,6; P. eryngii P-er – in 13,3 and T. hirsuta Th-11 – 19,2 times. Thus, GPS modifications were designed that enhance the model compound oxidative degradation efficiency and are the basis for further optimization of the selected xylotrophic basidiomycetes strains submerged cultivation conditions to increase biodegradation of xenobiotics. Keywords: xylotrophic basidiomycetes, submerged cultivation, biodegradation, Methyl Orange.
Millions of tons of fungal spores are dispersed in the atmosphere every year. These living cells, along with plant spores and pollen grains, may act as nuclei for condensation of water in clouds. ...Basidiospores released by mushrooms form a significant proportion of these aerosols, particularly above tropical forests. Mushroom spores are discharged from gills by the rapid displacement of a droplet of fluid on the cell surface. This droplet is formed by the condensation of water on the spore surface stimulated by the secretion of mannitol and other hygroscopic sugars. This fluid is carried with the spore during discharge, but evaporates once the spore is airborne. Using environmental electron microscopy, we have demonstrated that droplets reform on spores in humid air. The kinetics of this process suggest that basidiospores are especially effective as nuclei for the formation of large water drops in clouds. Through this mechanism, mushroom spores may promote rainfall in ecosystems that support large populations of ectomycorrhizal and saprotrophic basidiomycetes. Our research heightens interest in the global significance of the fungi and raises additional concerns about the sustainability of forests that depend on heavy precipitation.
The basidiomycete fungus Coprinopsis cinerea is an important model system for multicellular development. Fruiting bodies of C. cinerea are typical mushrooms, which can be produced synchronously on ...defined media in the laboratory. To investigate the transcriptome in detail during fruiting body development, high-throughput sequencing (RNA-seq) was performed using cDNA libraries strand-specifically constructed from 13 points (stages/tissues) with two biological replicates. The reads were aligned to 14,245 predicted transcripts, and counted for forward and reverse transcripts. Differentially expressed genes (DEGs) between two adjacent points and between vegetative mycelium and each point were detected by Tag Count Comparison (TCC). To validate RNA-seq data, expression levels of selected genes were compared using RPKM values in RNA-seq data and qRT-PCR data, and DEGs detected in microarray data were examined in MA plots of RNA-seq data by TCC. We discuss events deduced from GO analysis of DEGs. In addition, we uncovered both transcription factor candidates and antisense transcripts that are likely to be involved in developmental regulation for fruiting.
To elucidate the mechanisms of fruit body development in H. marmoreus, a total of 43609521 high-quality RNA-seq reads were obtained from four developmental stages, including the mycelial knot (H-M), ...mycelial pigmentation (H-V), primordium (H-P) and fruiting body (H-F) stages. These reads were assembled to obtain 40568 unigenes with an average length of 1074 bp. A total of 26800 (66.06%) unigenes were annotated and analyzed with the Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and Eukaryotic Orthologous Group (KOG) databases. Differentially expressed genes (DEGs) from the four transcriptomes were analyzed. The KEGG enrichment analysis revealed that the mycelium pigmentation stage was associated with the MAPK, cAMP, and blue light signal transduction pathways. In addition, expression of the two-component system members changed with the transition from H-M to H-V, suggesting that light affected the expression of genes related to fruit body initiation in H. marmoreus. During the transition from H-V to H-P, stress signals associated with MAPK, cAMP and ROS signals might be the most important inducers. Our data suggested that nitrogen starvation might be one of the most important factors in promoting fruit body maturation, and nitrogen metabolism and mTOR signaling pathway were associated with this process. In addition, 30 genes of interest were analyzed by quantitative real-time PCR to verify their expression profiles at the four developmental stages. This study advances our understanding of the molecular mechanism of fruiting body development in H. marmoreus by identifying a wealth of new genes that may play important roles in mushroom morphogenesis.
The biological activity of the edible basidiomycete Antrodia cinnamomea (AC) has been studied extensively. Many effects, such as anti-cancer, anti-inflammatory, and antioxidant activities, have been ...reported from either crude extracts or compounds isolated from AC. However, research addressing the function of AC in enhancing immunity is rare. The aim of the present study is to investigate the active components and the mechanism involved in the immunostimulatory effect of AC. We found that polysaccharides (PS) in the water extract of AC played a major role in dendritic cell (DC) activation, which is a critical leukocyte in initiating immune responses. We further size purified and identified that the high-molecular weight PS fraction (greater than 100 kDa) exhibited the activating effect. The AC high-molecular weight PSs (AC hmwPSs) promoted pro-inflammatory cytokine production by DCs and the maturation of DCs. In addition, DC-induced antigen-specific T cell activation and Th1 differentiation were increased by AC hmwPSs. In studying the molecular mechanism, we confirmed the activation of the MAPK and NF- Kappa B pathways in DCs after AC hmwPSs treatment. Furthermore, we demonstrated that TLR2 and TLR4 are required for the stimulatory activity of AC hmwPSs on DCs. In a mouse tumor model, we demonstrated that AC hmwPSs enhanced the anti-tumor efficacy of the HER-2/neu DNA vaccine by facilitating specific Th1 responses. Thus, we conclude that hmwPSs are the major components of AC that stimulate DCs via the TLR2/TLR4 and NF- Kappa B/MAPK signaling pathways. The AC hmwPSs have potential to be applied as adjuvants.
In grasslands, saprotrophic fungi, including basidiomycetes, are major decomposers of dead organic matter, although spatial distributions of their mycelial assemblages are little described. The aim ...of this study was to characterise the scale and distribution of saprotrophic fungal communities in a coastal grassland soil using terminal restriction fragment length polymorphism (T-RFLP). Soil fungi were sampled at Point Reyes, California, USA, by taking forty-five 26 mm diam. cores in a spatially defined manner. Within each sampled core, complete core sections at 1-2 cm and 14-15 cm depths were removed and sub-sampled for DNA extraction and amplification using the primer pairs ITS1F-FAM/ITS4 (general fungi) or ITS1F-FAM/ITS4B (basidiomycete-specific). Nonmetric Multidimensional Scaling showed that general fungal communities could be clearly separated by depth, although basidiomycete communities could not. There were no strong patterns of community similarity or dissimilarity for general or basidiomycete fungal communities at horizontal geographical distances from 25 cm to 96 m in the upper horizon. These results show considerable vertical, but little horizontal, variability in fungal community structure in a semi-natural grassland at the spatial scales measured here.
Anthropogenic release of biologically available N has increased atmospheric N deposition in forest ecosystems, which may slow decomposition by reducing the lignolytic activity of white-rot fungi. We ...investigated the potential for atmospheric N deposition to reduce the abundance and alter the composition of lignolytic basidiomycetes in a regional network of four northern hardwood forest stands receiving experimental NO super(-) sub(3) deposition (30 kg NO super(-) sub(3) -N ha super(-1) year super(-1)) for a decade. To estimate the abundance of basidiomycetes with lignolytic potential, we used PCR primers targeting laccase (polyphenol oxidase) and quantitative fluorescence PCR to estimate gene copy number. Natural variation in laccase gene size permitted use of length heterogeneity PCR to profile basidiomycete community composition across two sampling dates in forest floor and mineral soil. Although past work has identified significant and consistent negative effects of NO super(-) sub(3) deposition on lignolytic enzyme activity, microbial biomass, soil respiration, and decomposition rate, we found no consistent effect of NO super(-) sub(3) deposition on basidiomycete laccase gene abundance or community profile. Rather, laccase abundance under NO super(-) sub(3) deposition was lower (-52%), higher (+223%), or unchanged, depending on stand. Only a single stand exhibited a significant change in basidiomycete laccase gene profile. Basidiomycete laccase genes occurring in mineral soil were a subset of the genes observed in the forest floor. Moreover, significant effects on laccase abundance were confined to the forest floor, suggesting that species composition plays some role in determining how lignolytic basidiomycetes are affected by N deposition. Community profiles differed between July and October sampling dates, and basidiomycete communities sampled in October had lower laccase gene abundance in the forest floor, but higher laccase abundance in mineral soil. Although experimental N deposition significantly suppresses lignolytic activity in these forests, this change is not related to the abundance or community composition of basidiomycete fungi with laccase genes. Understanding the expression of laccases and other lignolytic enzymes by basidiomycete fungi and other lignin-decaying organisms appears to hold promise for explaining the consistent decline in lignolytic activity elicited by experimental N deposition.
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