Project description:Six new sorbicillinoids, trichoreeseione A (1) and B (2), trichodermolide B (3), 13-hydroxy-trichodermolide (4), 24-hydroxy-trichodimerol (5), 15-hydroxy-bisvertinol (7), together with three known analogs, trichodimerol (6), 24-hydroxy-bisvertinol (8), and bisvertinol (9), were isolated from the sponge-derived fungus Trichoderma reesei (HN-2016-018). Their structures including absolute configurations were elucidated by analysis of NMR, MS data, and calculated ECD spectra. Compounds 1 and 2 with a characteristic naphthalene-trione ring were firstly reported in sorbicillinoid family. Compounds 3 and 4 were two rare sorbicillinoids containing a unique bicycle [3.2.1] lactone skeleton, while 3 with a propan-2-one moiety was also recorded first time in this family. Compound 5 displayed cytotoxic activity against A549, MCF-7, and HCT116 cell lines with the IC50 values of 5.1, 9.5, and 13.7 μM, respectively.
Project description:Three new dimeric sorbicillinoids (1-3) and one new 3,4,6-trisubstituted α-pyrone (5), along with seven analogues (4 and 6-11), were isolated from the mangrove endophytic fungus Trichoderma reesei SCNU-F0042 under the guidance of molecular networking approach. Their chemical structures were established by 1D and 2D NMR HR-ESI-MS and ECD analysis. In a bioassay, compound 2 exhibited moderate SARS-CoV-2 inhibitory activity with an EC50 value of 29.0 μM.
Project description:Sorbicillinoids (also termed yellow pigment) are derived from either marine or terrestrial fungi, exhibit various biological activities and therefore show potential as commercial products for human or animal health. The cellulolytic filamentous fungus Trichoderma reesei is capable to biosynthesize sorbicillinoids, but the underlying regulatory mechanism is not yet completely clear. Herein, we identified a histone H3 lysine 9 (H3K9) methyltransferase, Dim5, in T. reesei. TrDIM5 deletion caused an impaired vegetative growth as well as conidiation, whereas the ∆Trdim5 strain displayed a remarkable increase in sorbicillinoid production. Post TrDIM5 deletion, the transcription of sorbicillinoid biosynthesis-related (SOR) genes was significantly upregulated with a more open chromatin structure. Intriguingly, hardly any expression changes occurred amongst those genes located on both flanks of the SOR gene cluster. In addition, the assays provided evidence that H3K9 triple methylation (H3K9me3) modification acted as a repressive marker at the SOR gene cluster and thus directly mediated the repression of sorbicillinoid biosynthesis. Transcription factor Ypr1 activated the SOR gene cluster by antagonizing TrDim5-mediated repression and therefore contributed to forming a relatively more open local chromatin environment, which further facilitated its binding and SOR gene expression. The results of this study will contribute to understanding the intricate regulatory network in sorbicillinoid biosynthesis and facilitate the endowment of T. reesei with preferred features for sorbicillinoid production by genetic engineering.
Project description:Antibacterial activity assessment and high performance liquid chromatography associated with nuclear magnetic resonance (HPLC/NMR) data revealed that the EtOAc extract of the fermented endophytic fungus Trichoderma saturnisporum DI-IA, obtained from the marine sponge Dictyonella incisa, contained conjugated olefinic metabolites with antibacterial activity. Chemical examination of the fungal strain resulted in the isolation of eight new sorbicillinoid-based compounds, namely saturnispols A⁻H (1⁻8). Their structures were determined on the basis of extensive spectroscopic analysis, including the experimental and calculated electronic circular dichroism (ECD) data for the configurational assignments. Saturnispol F exerted significant inhibition against a panel of bacteria strains including vancomycin-resistant enterococci (VRE) with a minimum inhibitory concentrations (MIC) ranging from 1.63 to 12.9 μg/mL, while saturnispol H showed selective effects against VRE and B. subtilis.
Project description:Three new sorbicillinoid derivatives, citrinsorbicillinol A-C (1-3), along with three known compounds, such as trichosorbicillin G (4), dibutyl phthalate (5), and 3-(4-methoxyphenyl) propanoic acid (6), were isolated from the endophyte Trichoderma citrinoviride of Coptis chinensis. Their structures were elucidated through extensive analyses of spectroscopic data, computer-assisted structure elucidation (ACD/Structure Elucidator), density functional theory (DFT) calculations of the nuclear magnetic resonance (NMR) spectra, and electronic circular dichroism (ECD). Biologically, compounds 1-4 exhibited potential antioxidant activity, as assessed using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, with IC50 values ranging from 27.8 to 89.6 μM. In particular, compounds 2 and 3 demonstrated radical scavenging activity comparable to that of the positive control, ascorbic acid, with IC50 values of 27.8 and 31.2 μM, respectively. Moreover, compound 1 exhibited potential anti-inflammatory activity by inhibiting nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages, with an IC50 value of 52.7 μM. These findings underscore the therapeutic potential of the new sorbicillinoid derivatives for antioxidant and anti-inflammatory applications.
Project description:Sorbicillinoids are a diverse group of yellow secondary metabolites that are produced by a range of not closely related ascomycetes, including Penicillium chrysogenum, Acremonium chrysogenum, and Trichoderma reesei. They share a similarity to the name-giving compound sorbicillin, a hexaketide. Previously, a conserved gene cluster containing two polyketide synthases has been identified as the source of sorbicillin, and a model for the biosynthesis of sorbicillin in P. chrysogenum has been proposed. In this study, we deleted the major genes of interest of the cluster in T. reesei, namely sor1, sor3, and sor4. Sor1 is the homolog of P. chrysogenum SorA, which is the first polyketide synthase of the proposed biosynthesis pathway. Sor3 is a flavin adenine dinucleotide (FAD)-dependent monooxygenase, and its homolog in P. chrysogenum, SorC, was shown to oxidize sorbicillin and 2',3'-dihydrosorbicillin to sorbicillinol and 2',3'-dihydrosorbicillinol, respectively, in vitro. Sor4 is an FAD/flavin mononucleotide-containing dehydrogenase with an unknown function. We measured the amounts of synthesized sorbicillinoids throughout growth and could verify the roles of Sor1 and Sor3 in vivo in T. reesei. In the absence of Sor4, two compounds annotated to dihydrosorbicillinol accumulate in the supernatant and only small amounts of sorbicillinol are synthesized. Therefore, we suggest extending the current biosynthesis model about Sor4 reducing 2',3'-dihydrosorbicillin and 2',3'-dihydrosorbicillinol to sorbicillinol and sorbicillinol, respectively. Sorbicillinol turned out to be the main chemical building block for most sorbicillinoids, including oxosorbicillinol, bisorbicillinol, and bisvertinolon. Further, we detected the sorbicillinol-dependent synthesis of 5-hydroxyvertinolide at early time points, which contradicts previous models for biosynthesis of 5-hydroxyvertinolide. Finally, we investigated whether sorbicillinoids from T. reesei have a growth limiting effect on the fungus itself or on plant pathogenic fungi or on pathogenic bacteria.
Project description:BackgroundTrichoderma reesei is the most important industrial producer of lignocellulolytic enzymes. These enzymes play an important role in biomass degradation leading to novel applications of this fungus in the biotechnology industry, specifically biofuel production. The secretory pathway of fungi is responsible for transporting proteins addressed to different cellular locations involving some cellular endomembrane systems. Although protein secretion is an extremely efficient process in T. reesei, the mechanisms underlying protein secretion have remained largely uncharacterized in this organism.ResultsHere, we report for the first time the isolation and characterization of T. reesei extracellular vesicles (EVs). Using proteomic analysis under cellulose culture condition, we have confidently identified 188 vesicular proteins belonging to different functional categories. Also, we characterized EVs production using transmission electron microscopy in combination with light scattering analysis. Biochemical assays revealed that T. reesei extracellular vesicles have an enrichment of filter paper (FPase) and β-glucosidase activities in purified vesicles from 24, 72 and 96, and 72 and 96 h, respectively. Furthermore, our results showed that there is a slight enrichment of small RNAs inside the vesicles after 96 h and 120 h, and presence of hsp proteins inside the vesicles purified from T. reesei grown in the presence of cellulose.ConclusionsThis work points to important insights into a better understanding of the cellular mechanisms underlying the regulation of cellulolytic enzyme secretion in this fungus.
Project description:The properties and enzymic activity of endoglucanases (EC 3.2.1.4) of the fungus Trichoderma reesei were studied by means of immunological methods and by using polyglycosidic substrates. Endoglucanases exist in the culture liquid as a series of immunologically related components. The most active endoglucanase component has an Mr of 43 000 and pI value of 4.0. The most abundant components have a value of pI about 5.0, an Mr of 56 000-67 000 and specific activity only one-fifth of that of the pI-4.0 component. During purification and storage the endoglucanases are spontaneously modified; the relative proportion of components having greater Mr values, more alkaline pI values and lower specific activities is increased. The hexose content of the endoglucanase components is 2-7%. Endoglucanases hydrolyse soluble beta-1,4 glycans. The enzymes described here differ from endoglucanase preparations described previously in not showing activity towards insoluble substrates. The role of endoglucanases in wood hydrolysis is consequently limited to the stage where wood constituents are already in soluble form.
Project description:Filamentous fungi have wide applications in biotechnology. The CRISPR/Cas9 system is a powerful genome-editing method that facilitates genetic alterations of genomes in a variety of organisms. However, a genome-editing approach has not been reported in filamentous fungi. Here, we demonstrated the establishment of a CRISPR/Cas9 system in the filamentous fungus Trichoderma reesei by specific codon optimization and in vitro RNA transcription. It was shown that the CRISPR/Cas9 system was controllable and conditional through inducible Cas9 expression. This system generated site-specific mutations in target genes through efficient homologous recombination, even using short homology arms. This system also provided an applicable and promising approach to targeting multiple genes simultaneously. Our results illustrate that the CRISPR/Cas9 system is a powerful genome-manipulating tool for T. reesei and most likely for other filamentous fungal species, which may accelerate studies on functional genomics and strain improvement in these filamentous fungi.
Project description:Five new naphthalenones, two enantiomers (−)-1 and (+)-1 leptothalenone A, (−)-4,8-dihydroxy-7-(2-hydroxy-ethyl)-6-methoxy-3,4-dihydro-2H-naphthalen-1-one ((−)-2), (4S, 10R, 4’S)-leptotha-lenone B (5), (4R, 10S, 4’S)-leptothalenone B (6), and a new isocoumarine, 6-hydroxy-5,8-dimethoxy-3-methyl-1H-isochromen-1-one (4), along with two known compounds (+)-4,8-dihydroxy-7-(2-hydroxy-ethyl)-6-methoxy-3,4-dihydro-2H-naphthalen-1-one ((+)-2) and (+)-10-norparvulenone (3) were isolated from the marine-derived fungus Leptosphaerulina chartarum 3608. The structures of new compounds were elucidated by HR-ESIMS, NMR, and ECD analysis. All compounds were evaluated for cytotoxicity and anti-inflammatory activity. Compound 6 showed moderate anti-inflammatory activity by inhibiting the production of nitric oxide (NO) in lipopolysaccharide-stimulated RAW264.7 cells, with an IC50 value of 44.5 μM.