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1.
Photochem Photobiol Sci ; 23(5): 941-955, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38643418

RESUMEN

The identification of more efficient, clean, secure, and competitive energy supply is necessary to align with the needs of sustainable devices. For this reason, a study for developing innovative dye-sensitized solar cells (DSSCs) based on microbial pigments is reported starting from Talaromyces atroroseus GH2. The fungus was cultivated by fermentation and the extracellular pigment extract was characterized by HPLC-DAD-ESI-MS analyses. The most abundant compound among the 22 azaphilone-type pigments identified was represented by PP-O. The device's behavior was investigated in relation to electrolyte and pH for verifying the stability on time and the photovoltaic performance. Devices obtained were characterized by UV-vis measurements to verify the absorbance intensity and transmittance percentage. Moreover, photovoltaic parameters through photo-electrochemical measurements (I-V curves) and impedance characteristics by Electrochemical Impedance Spectroscopy (EIS) were determined. The best microbial device showed a short-circuit current density (Jsc) of 0.69 mA/cm2, an open-circuit photo-voltage (Voc) of 0.27 V and a Fill Factor (FF) of 0.60. Furthermore, the power conversion efficiency (PCE) of the device was 0.11%. Thus, the present study demonstrated the potential of microbial origin pigments for developing DSSCs.


Asunto(s)
Colorantes , Energía Solar , Talaromyces , Talaromyces/química , Talaromyces/metabolismo , Colorantes/química , Pigmentos Biológicos/química
2.
J Nat Prod ; 87(4): 935-947, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38575516

RESUMEN

We report on the use of nitric oxide-mediated transcriptional activation (NOMETA) as an innovative means to detect and access new classes of microbial natural products encoded within silent biosynthetic gene clusters. A small library of termite nest- and mangrove-derived fungi and actinomyces was subjected to cultivation profiling using a miniaturized 24-well format approach (MATRIX) in the presence and absence of nitric oxide, with the resulting metabolomes subjected to comparative chemical analysis using UPLC-DAD and GNPS molecular networking. This strategy prompted study of Talaromyces sp. CMB-TN6F and Coccidiodes sp. CMB-TN39F, leading to discovery of the triterpene glycoside pullenvalenes A-D (1-4), featuring an unprecedented triterpene carbon skeleton and rare 6-O-methyl-N-acetyl-d-glucosaminyl glycoside residues. Structure elucidation of 1-4 was achieved by a combination of detailed spectroscopic analysis, chemical degradation, derivatization and synthesis, and biosynthetic considerations.


Asunto(s)
Aminoglicósidos , Isópteros , Óxido Nítrico , Triterpenos , Animales , Triterpenos/farmacología , Triterpenos/química , Triterpenos/metabolismo , Óxido Nítrico/biosíntesis , Óxido Nítrico/metabolismo , Estructura Molecular , Isópteros/microbiología , Aminoglicósidos/farmacología , Australia , Activación Transcripcional/efectos de los fármacos , Hongos/metabolismo , Talaromyces/química , Talaromyces/metabolismo , Actinomyces/metabolismo , Actinomyces/efectos de los fármacos
3.
Bioorg Chem ; 147: 107417, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38701596

RESUMEN

Marine natural products play an important role in biopesticides. Seven new secondary metabolites with different structural classes, including two cycloheptapeptides, scortide A (1) and scortide B (2), two 19-nor-diterpenoids, talascortene H (3) and talascortene I (4), two diterpenoid acids, talascortene J (5) and talascortene K (6), and one triterpenoid, talascortene L (7) were isolated and identified from the sea-anemone-derived endozoic fungus Talaromyces scorteus AS-242. Their structures were comprehensively assigned by spectroscopic data analysis, single-crystal X-ray diffraction, tandem mass spectrometry, and electronic circular dichroism (ECD) calculations. The result of the antimicrobial assay demonstrated that compounds 1 - 6 have inhibitory activity against several human, aquatic, and plant pathogens with minimum inhibitory concentration (MIC) values ranging from 1 to 64 µg/mL. Specially, compounds 2 and 4 showed significant activities against the pathogenic fungus Curvularia spicifera with the MIC value of 1 µg/mL, providing an experimental basis of 2 and 4 with the potential as lead compounds to be developed into biopesticides.


Asunto(s)
Pruebas de Sensibilidad Microbiana , Talaromyces , Humanos , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Fungicidas Industriales/farmacología , Fungicidas Industriales/química , Fungicidas Industriales/aislamiento & purificación , Estructura Molecular , Relación Estructura-Actividad , Talaromyces/química , Talaromyces/metabolismo , Diterpenos/química , Diterpenos/aislamiento & purificación , Diterpenos/farmacología
4.
Phytopathology ; 114(3): 618-629, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37889191

RESUMEN

The dynamic of plant-parasitic nematode populations in soil is closely related to soil microorganisms. Fungi from Heterodera zeae cysts were isolated to explore the phenomenon of decline in the H. zeae population in the soil. Phylogenetic study of partial ITS, BenA, CaM, and RPB2 gene sequences, in addition to morphological investigations, was utilized to identify a nematode-destroying fungus. The nematicidal activity of a novel strain GX1 against H. zeae was assessed in vitro and in the greenhouse. Our findings revealed that strain GX1 is a new species of Talaromyces, named Talaromyces cystophila. It has a strong parasitic and lethal effect on H. zeae cysts, with 91.11% parasitism on cysts at 3 days after treatment. The contents of second-stage juveniles (J2s) and eggs inside the cysts were degraded and formed dense vacuoles, and the damaged eggs could not hatch normally. The spore suspension exhibited high nematophagous activity against nematodes, and fermentation filtrate exhibited marked inhibition of egg hatching and nematicidal activities on J2s. The hatching inhibition rates of eggs exposed to 1 × 108 CFU/ml spore suspensions or 20% 1-week fermentation filtrate (1-WF) for 15 days were 98.56 and 100%, respectively. The mortality of J2s exposed to 1 × 108 CFU/ml spore suspension reached 100% at 24 h; exposure to 50% 2-WF was 98.65 and 100% at 24 and 48 h, respectively. Greenhouse experiments revealed that the spore suspension and fermentation broth considerably decreased H. zeae reproduction by 56.17 to 78.76%. T. cystophila is a potential biocontrol strain with nematophagous and nematicidal activity that deserves attention and application.


Asunto(s)
Quistes , Talaromyces , Tylenchida , Tylenchoidea , Animales , Zea mays , Talaromyces/metabolismo , Filogenia , Enfermedades de las Plantas/prevención & control , Enfermedades de las Plantas/parasitología , Antinematodos/farmacología , Suelo
5.
Mar Drugs ; 22(5)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38786595

RESUMEN

Thirty-two fungal polyketide derivatives, including eleven new compounds, namely (3R,5'R)-5-hydroxytalaroflavone (1), talaroisochromenols A-C (3, 5, and 11), (8R,9R,10aR)-5-hydroxyaltenuene (13), (8R,9R,10aS)-5-hydroxyaltenuene (14), (8R,9S,10aR)-5-hydroxyaltenuene (15), nemanecins D and E (25 and 26), 2,5-dimethyl-8-iodochromone (27), and talarofurolactone A (29), together with one new naturally occurring but previously synthesized metabolite, 6-hydroxy-4-methoxycoumarin (28), were isolated and identified from the deep-sea cold-seep-derived fungus Talaromyces sp. CS-258. Among them, racemic ((±)-11) or epimeric (13-15, 25, and 26) mixtures were successfully separated by chiral or gradient elution HPLC. Meanwhile, compound 27 represents a rarely reported naturally occurring iodinated compound. Their planar structures as well as absolute configurations were determined by extensive analysis via NMR, MS, single-crystal X-ray diffraction, Mosher's method, and ECD or NMR calculation (with DP4+ probability analysis). Possible biosynthetic routes of some isolated compounds, which are related to chromone or isochromone biosynthetic pathways, were put forward. The biological analysis results revealed that compounds 7, 9, 10, 18-22, 24, 30, and 31 showed broad-spectrum antibacterial activities against several human and aquatic pathogens with MIC ranges of 0.5-64 µg/mL.


Asunto(s)
Antibacterianos , Policétidos , Talaromyces , Talaromyces/química , Talaromyces/metabolismo , Policétidos/farmacología , Policétidos/química , Policétidos/aislamiento & purificación , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Estructura Molecular
6.
Mar Drugs ; 21(12)2023 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-38132949

RESUMEN

Heterologous biosynthesis has become an effective means to activate fungal silent biosynthetic gene clusters (BGCs) and efficiently utilize fungal genetic resources. Herein, thirteen labdane diterpene derivatives, including five undescribed ones named talarobicins A-E (3-7), were discovered via heterologous expression of a silent BGC (labd) in Aspergillus nidulans. Their structures with absolute configurations were elucidated using extensive MS and NMR spectroscopic methods, as well as electronic circular dichroism (ECD) calculations. These labdanes belong to four skeleton types, and talarobicin B (4) is the first 3,18-dinor-2,3:4,18-diseco-labdane diterpene with the cleavage of the C2-C3 bond in ring A and the decarboxylation at C-3 and C-18. Talarobicin B (4) represents the key intermediate in the biosynthesis of penioxalicin and compound 13. The combinatorial heterologous expression and feeding experiments revealed that the cytochrome P450 enzymes LabdC, LabdE, and LabdF were responsible for catalyzing various chemical reactions, such as oxidation, decarboxylation, and methylation. All of the compounds are noncytotoxic, and compounds 2 and 8 displayed inhibitory effects against methicillin-resistant coagulase-negative staphylococci (MRCNS) and Bacillus cereus.


Asunto(s)
Aspergillus nidulans , Diterpenos , Talaromyces , Talaromyces/metabolismo , Diterpenos/química , Sistema Enzimático del Citocromo P-450 , Espectroscopía de Resonancia Magnética , Aspergillus nidulans/genética , Aspergillus nidulans/metabolismo , Estructura Molecular
7.
Chembiochem ; 23(2): e202100352, 2022 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-34375042

RESUMEN

The fungal metabolite Fosfonochlorin features a chloroacetyl moiety that is unusual within known phosphonate natural product biochemistry. Putative biosynthetic genes encoding Fosfonochlorin in Fusarium and Talaromyces spp. were investigated through reactions of encoded enzymes with synthetic substrates and isotope labelling studies. We show that the early biosynthetic steps for Fosfonochlorin involve the reduction of phosphonoacetaldehyde to form 2-hydroxyethylphosphonic acid, followed by oxidative intramolecular cyclization of the resulting alcohol to form (S)-epoxyethylphosphonic acid. The latter reaction is catalyzed by FfnD, a rare example of a non-heme iron/2-(oxo)glutarate dependent oxacyclase. In contrast, FfnD behaves as a more typical oxygenase with ethylphosphonic acid, producing (S)-1-hydroxyethylphosphonic acid. FfnD thus represents a new example of a ferryl generating enzyme that can suppress the typical oxygen rebound reaction that follows abstraction of a substrate hydrogen by a ferryl oxygen, thereby directing the substrate radical towards a fate other than hydroxylation.


Asunto(s)
Compuestos Ferrosos/metabolismo , Fusarium/metabolismo , Ácidos Cetoglutáricos/metabolismo , Organofosfonatos/metabolismo , Talaromyces/metabolismo , Ciclización , Hidroxilación , Compuestos Organofosforados/metabolismo , Oxidación-Reducción
8.
Arch Microbiol ; 204(9): 570, 2022 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-35994127

RESUMEN

The microbial biotransformation is a robust procedure in developing steroids and fungi are practical tools in this process; therefore, the fungal modification of testosterone by Penicillium pinophilum was investigated. The three prominent metabolites, including 14α-hydroxyandrost-4-en-3,17-dione (II), 14α-hydroxytestosterone (III), and 11α-hydroxytestosterone (IV), were isolated and characterized by chromatographic and spectroscopic methods. The time course profile showed that the content of the metabolites II and III began to decrease after 96 and 24 h, respectively. In comparison, the content of the metabolite IV remained stable after 24 h. In silico studies showed that the probability of binding to the androgen receptor remains high for all three metabolites. However, the probability of binding to the estrogen receptors α and ß increased for metabolite IV but decreased for metabolite III. Penicillium pinophilum as a potentially viable biocatalyst could hydroxylate C-11α and C-14α positions and oxidize the C-17ß hydroxyl group to 17-ketone in testosterone molecule.


Asunto(s)
Penicillium , Talaromyces , Biotransformación , Hidroxitestosteronas , Penicillium/genética , Penicillium/metabolismo , Talaromyces/metabolismo , Testosterona/metabolismo
9.
Biometals ; 35(2): 335-348, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35195804

RESUMEN

Fungi have received particular attention in regards to alternatives for bioremediation of heavy metal contaminated locales. Enzymes produced by filamentous fungi, such as phosphatases, can precipitate heavy metal ions in contaminated environments, forming metal phosphates (insoluble). Thus, this research aimed to analyze fungi for uranium biomineralization capacity. For this, Gongronella butleri, Penicillium piscarium, Rhodotorula sinensis and Talaromyces amestolkiae were evaluated. Phytate and glycerol 2-phosphate were used as the phosphate sources in the culture media at pH 3.5 and 5.5, with and without uranium ions. After 4 weeks of fungal growth, evaluated fungi were able to produce high concentrations of phosphates in the media. T. amestolkiae was the best phosphate producer, using phytate as an organic source. During fungal growth, there was no change in pH level of the culture medium. After 3 weeks of T. amestolkiae growth in medium supplemented with phytate, there was a reduction between 20 and 30% of uranium concentrations, with high precipitation of uranium and phosphate on the fungal biomass. The fungi analyzed in this research can use the phytic acid present in the medium and produce high concentrations of phosphate; which, in the environment, can assist in the heavy metal biomineralization processes, even in acidic environments. Such metabolic capabilities of fungi can be useful in decontaminating uranium-contaminated environments.


Asunto(s)
Talaromyces , Uranio , Organofosfatos , Talaromyces/metabolismo , Agua
10.
Biosci Biotechnol Biochem ; 86(4): 435-443, 2022 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-35108363

RESUMEN

Talaromyces islandicus is a unique fungus that produces more than 20 numbers of anthraquinones (AQs) and their dimeric natural products, bisanthraquinones (BQs). These compounds share a 9,10-anthracenedione core derived from emodin. The biosynthetic pathway of emodin has been firmly established, while that of other AQs and BQs is still unclear. In this study, we identified the biosynthetic gene clusters for chrysophanol and skyrin. The function of key modification enzymes was examined by performing biotransformation experiments and in vitro enzymatic reactions with emodin and its derivatives, allowing us to propose a mechanism for the modification reactions. The present study provides insight into the biosynthesis of AQs and BQs in T. islandicus.


Asunto(s)
Emodina , Talaromyces , Antraquinonas/metabolismo , Biotransformación , Talaromyces/metabolismo
11.
Mar Drugs ; 20(2)2022 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-35200609

RESUMEN

Seven new compounds, namely talaromanloid A (1), talaromydene (2), 10-hydroxy-8-demethyltalaromydine and 11-hydroxy-8-demethyltalaromydine (3 and 4), talaromylectone (5), and ditalaromylectones A and B (6 and 7), together with seven known compounds were identified from a marine-derived fungus, Talaromyces mangshanicus BTBU20211089, which was isolated from a sediment sample collected from the South China Sea. Their chemical structures were determined using spectroscopic data, including HRESIMS, 1D, and 2D NMR techniques. The absolute configurations of 1 and 2 were elucidated by comparing experimental and calculated ECD spectra. Compounds 1, 2, 6, and 7 are new compounds possessing a novel carbon skeleton. Compound 6 is a dimeric molecule of 3 and 9. Compound 7 shared a unique structure of the cyclized dimer of 3 and 4. All the compounds were tested for their bioactivities against Staphylococcus aureus, Escherichia coli, and Candida albicans.


Asunto(s)
Antiinfecciosos/farmacología , Sedimentos Geológicos/microbiología , Talaromyces/metabolismo , Antiinfecciosos/aislamiento & purificación , Candida albicans/efectos de los fármacos , China , Escherichia coli/efectos de los fármacos , Océanos y Mares , Metabolismo Secundario , Staphylococcus aureus/efectos de los fármacos
12.
Int J Mol Sci ; 23(3)2022 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-35163307

RESUMEN

The study of endoxylanases as catalysts to valorize hemicellulosic residues and to obtain glycosides with improved properties is a topic of great industrial interest. In this work, a GH10 ß-1,4-endoxylanase (XynSOS), from the ascomycetous fungus Talaromyces amestolkiae, has been heterologously produced in Pichia pastoris, purified, and characterized. rXynSOS is a highly glycosylated monomeric enzyme of 53 kDa that contains a functional CBM1 domain and shows its optimal activity on azurine cross-linked (AZCL)-beechwood xylan at 70 °C and pH 5. Substrate specificity and kinetic studies confirmed its versatility and high affinity for beechwood xylan and wheat arabinoxylan. Moreover, rXynSOS was capable of transglycosylating phenolic compounds, although with low efficiencies. For expanding its synthetic capacity, a glycosynthase variant of rXynSOS was developed by directed mutagenesis, replacing its nucleophile catalytic residue E236 by a glycine (rXynSOS-E236G). This novel glycosynthase was able to synthesize ß-1,4-xylooligosaccharides (XOS) of different lengths (four, six, eight, and ten xylose units), which are known to be emerging prebiotics. rXynSOS-E236G was also much more active than the native enzyme in the glycosylation of a broad range of phenolic compounds with antioxidant properties. The interesting capabilities of rXynSOS and its glycosynthase variant make them promising tools for biotechnological applications.


Asunto(s)
Glucuronatos/metabolismo , Glicósidos/metabolismo , Oligosacáridos/metabolismo , Fenoles/metabolismo , Talaromyces/metabolismo , Endo-1,4-beta Xilanasas/metabolismo , Cinética , Pichia/metabolismo , Prebióticos/microbiología , Especificidad por Sustrato , Xilanos/metabolismo , Xilosa/metabolismo
13.
Molecules ; 27(14)2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35889347

RESUMEN

Polyesters containing 2,4-dihydroxy-6-(2-hydroxypropyl)benzoate and 3-hydroxybutyrate moieties have been isolated from many fungal species. Talaromyces stipitatus was previously reported to produce a similar polyester, talapolyester G. The complete genome sequence and the development of bioinformatics tools have enabled the discovery of the biosynthetic potential of this microorganism. Here, a putative biosynthetic gene cluster (BGC) of the polyesters encoding a highly reducing polyketide synthase (HR-PKS) and nonreducing polyketide synthase (NR-PKS), a cytochrome P450 and a regulator, was identified. Although talapolyester G does not require an oxidative step for its biosynthesis, further investigation into the secondary metabolite production of T. stipitatus resulted in isolating two new metabolites called talarodioxadione and talarooxime, in addition to three known compounds, namely 6-hydroxymellein, 15G256α and transtorine that have never been reported from this organism. Interestingly, the biosynthesis of the cyclic polyester 15G256α requires hydroxylation of an inactive methyl group and thus could be a product of the identified gene cluster. The two compounds, talarooxime and transtorine, are probably the catabolic metabolites of tryptophan through the kynurenine pathway. Tryptophan metabolism exists in almost all organisms and has been of interest to many researchers. The biosynthesis of the new oxime is proposed to involve two subsequent N-hydroxylation of 2-aminoacetophenone.


Asunto(s)
Policétidos , Talaromyces , Familia de Multigenes , Poliésteres , Sintasas Poliquetidas/metabolismo , Policétidos/metabolismo , Talaromyces/genética , Talaromyces/metabolismo , Triptófano/genética
14.
J Am Chem Soc ; 143(35): 14218-14226, 2021 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-34432466

RESUMEN

Skyrin and rugulosin A are bioactive bisanthraquinones found in many fungi, with the former suggested as a precursor of hypericin (a diversely bioactive phytochemical) and the latter characterized by its distinct cage-like structure. However, their biosynthetic pathways remain mysterious, although they have been characterized for over six decades. Here, we present the rug gene cluster that governs simultaneously the biosynthesis of skyrin and rugulosin A in Talaromyces sp. YE3016, a fungal endophyte residing in Aconitum carmichaeli. A combination of genome sequencing, gene inactivation, heterologous expression, and biotransformation tests allowed the identification of the gene function, biosynthetic precursor, and enzymatic sets involved in their molecular architecture constructions. In particular, skyrin was demonstrated to form from the 5,5'-dimerization of emodin radicals catalyzed by RugG, a cytochrome P450 monooxygenase evidenced to be potentially applicable for the (chemo)enzymatic synthesis of dimeric polyphenols. The fungal aldo-keto reductase RugH was shown to be capable of hijacking the closest skyrin precursor (CSP) immediately after the emodin radical coupling, catalyzing the ketone reduction of CSP to inactivate its tautomerization into skyrin and thus allowing for the spontaneous intramolecular Michael addition to cyclize the ketone-reduced form of CSP into rugulosin A, a representative of diverse cage-structured bisanthraquinones. Collectively, the work updates our understanding of bisanthraquinone biosynthesis and paves the way for synthetic biology accesses to skyrin, rugulosin A, and their siblings.


Asunto(s)
Antraquinonas/metabolismo , Aldo-Ceto Reductasas/genética , Aldo-Ceto Reductasas/metabolismo , Aspergillus oryzae/genética , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Familia de Multigenes , Talaromyces/genética , Talaromyces/metabolismo
15.
Mar Drugs ; 19(5)2021 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-33925595

RESUMEN

Pigment production from filamentous fungi is gaining interest due to the diversity of fungal species, the variety of compounds synthesized, and the possibility of controlled massive productions. The Talaromyces species produce a large panel of metabolites, including Monascus-like azaphilone pigments, with potential use as natural colorants in industrial applications. Optimizing pigment production from fungal strains grown on different carbon and nitrogen sources, using statistical methods, is widespread nowadays. The present work is the first in an attempt to optimize pigments production in a culture of the marine-derived T. albobiverticillius 30548, under the influence of several nutrients sources. Nutrient combinations were screened through the one-variable-at-a-time (OVAT) analysis. Sucrose combined with yeast extract provided a maximum yield of orange pigments (OPY) and red pigments (RPY) (respectively, 1.39 g/L quinizarin equivalent and 2.44 g/L Red Yeast pigment equivalent), as well as higher dry biomass (DBW) (6.60 g/L). Significant medium components (yeast extract, K2HPO4 and MgSO4·7H2O) were also identified from one-variable-at-a-time (OVAT) analysis for pigment and biomass production. A five-level central composite design (CCD) and a response surface methodology (RSM) were applied to evaluate the optimal concentrations and interactive effects between selected nutrients. The experimental results were well fitted with the chosen statistical model. The predicted maximum response for OPY (1.43 g/L), RPY (2.59 g/L), and DBW (15.98 g/L) were obtained at 3 g/L yeast extract, 1 g/L K2HPO4, and 0.2 g/L MgSO4·7H2O. Such optimization is of great significance for the selection of key nutrients and their concentrations in order to increase the pigment production at a pilot or industrial scale.


Asunto(s)
Microbiología Industrial , Pigmentos Biológicos/metabolismo , Talaromyces/metabolismo , Biomasa , Sedimentos Geológicos/microbiología , Sulfato de Magnesio/metabolismo , Modelos Estadísticos , Fosfatos/metabolismo , Compuestos de Potasio/metabolismo , Sacarosa/metabolismo , Talaromyces/crecimiento & desarrollo , Levaduras/metabolismo
16.
Mar Drugs ; 19(9)2021 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-34564154

RESUMEN

Eight new compounds, including two sambutoxin derivatives (1-2), two highly oxygenated cyclopentenones (7-8), four highly oxygenated cyclohexenones (9-12), together with four known sambutoxin derivatives (3-6), were isolated from semimangrove endophytic fungus Talaromyces sp. CY-3, under the guidance of molecular networking. The structures of new isolates were elucidated by analysis of detailed spectroscopic data, ECD spectra, chemical hydrolysis, 13C NMR calculation, and DP4+ analysis. In bioassays, compounds 1-5 displayed better α-glucosidase inhibitory activity than the positive control 1-deoxynojirimycin (IC50 = 80.8 ± 0.3 µM), and the IC50 value was in the range of 12.6 ± 0.9 to 57.3 ± 1.3 µM.


Asunto(s)
Endófitos/metabolismo , Inhibidores de Glicósido Hidrolasas/metabolismo , Malvaceae/microbiología , Micotoxinas/metabolismo , Policétidos/metabolismo , Talaromyces/metabolismo , Inhibidores de Glicósido Hidrolasas/química , Estructura Molecular , Micotoxinas/química , Policétidos/química , Metabolismo Secundario , alfa-Glucosidasas/química
17.
Int J Mol Sci ; 22(24)2021 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-34948409

RESUMEN

The first lytic polysaccharide monooxygenase (LPMO) detected in the genome of the widespread ascomycete Talaromyces amestolkiae (TamAA9A) has been successfully expressed in Pichia pastoris and characterized. Molecular modeling of TamAA9A showed a structure similar to those from other AA9 LPMOs. Although fungal LPMOs belonging to the genera Penicillium or Talaromyces have not been analyzed in terms of regioselectivity, phylogenetic analyses suggested C1/C4 oxidation which was confirmed by HPAEC. To ascertain the function of a C-terminal linker-like region present in the wild-type sequence of the LPMO, two variants of the wild-type enzyme, one without this sequence and one with an additional C-terminal carbohydrate binding domain (CBM), were designed. The three enzymes (native, without linker and chimeric variant with a CBM) were purified in two chromatographic steps and were thermostable and active in the presence of H2O2. The transition midpoint temperature of the wild-type LPMO (Tm = 67.7 °C) and its variant with only the catalytic domain (Tm = 67.6 °C) showed the highest thermostability, whereas the presence of a CBM reduced it (Tm = 57.8 °C) and indicates an adverse effect on the enzyme structure. Besides, the potential of the different T. amestolkiae LPMO variants for their application in the saccharification of cellulosic and lignocellulosic materials was corroborated.


Asunto(s)
Celulosa/metabolismo , Proteínas Fúngicas/metabolismo , Oxigenasas de Función Mixta/metabolismo , Talaromyces/metabolismo , Secuencia de Aminoácidos , Celulosa/química , Estabilidad de Enzimas , Proteínas Fúngicas/química , Oxigenasas de Función Mixta/química , Modelos Moleculares , Conformación Proteica , Alineación de Secuencia , Especificidad por Sustrato , Talaromyces/química , Talaromyces/enzimología
18.
J Struct Biol ; 210(1): 107463, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-31978464

RESUMEN

The unusual diterpene (C20) synthase copalyl diphosphate synthase from Penicillium verruculosum (PvCPS) is the first bifunctional terpene synthase identified with both prenyltransferase and class II cyclase activities in a single polypeptide chain with αßγ domain architecture. The C-terminal prenyltransferase α domain generates geranylgeranyl diphosphate which is then cyclized to form copalyl diphosphate at the N-terminal ßγ domain interface. We now demonstrate that PvCPS exists as a hexamer at high concentrations - a unique quaternary structure for known αßγ terpene synthases. Hexamer assembly is corroborated by a 2.41 Å-resolution crystal structure of the α domain prenyltransferase obtained from limited proteolysis of full-length PvCPS, as well as the ab initio model of full-length PvCPS derived from small-angle X-ray scattering data. Hexamerization of the prenyltransferase α domain appears to drive the hexamerization of full-length PvCPS. The PvCPS hexamer dissociates into lower-order species at lower concentrations, as evidenced by size-exclusion chromatography in-line with multiangle light scattering, sedimentation velocity analytical ultracentrifugation, and native polyacrylamide gel electrophoresis experiments, suggesting that oligomerization is concentration dependent. Even so, PvCPS oligomer assembly does not affect prenyltransferase activity in vitro.


Asunto(s)
Transferasas Alquil y Aril/metabolismo , Terpenos/metabolismo , Transferasas Alquil y Aril/genética , Dimetilaliltranstransferasa/metabolismo , Fosfatos de Poliisoprenilo/metabolismo , Talaromyces/metabolismo
19.
J Am Chem Soc ; 142(4): 1957-1965, 2020 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-31904941

RESUMEN

Fungal polyketide-nonribosomal peptide (PK-NRP) hybrid macrolactones are a growing family of natural products with biomedical and agricultural activities. One of the most important families is the thermolides, which are produced by extreme thermophilic fungi and exhibit strong nematocidal activity. We show here that the genes ThmABCE from Talaromyces thermophilus NRRL 2155 are critical for thermolide synthesis. Two separate single-module hrPKS (ThmA) and NRPS (ThmB) enzymes collaborate to synthesize the core macrolactone backbone (6 or 7), and the NRPS ThmB-CT domain catalyzes the key macrocyclization step in PK-NRP intermediate release via ester bond formation, representing a novel function of fungal NRPS C domains. We also show that heterologous and engineered expression of the Thm genes in the type strains of Aspergillus nidulans and Escherichia coli not only dramatically enhances the yields of thermolides but also affords different esterified analogues, such as butyryl- (thermolides J and K, 15 and 16), hexanoyl-, and octanyl- derivatives or mixed thermolides. Thermolides L and M (18 and 19), discovered via genome mining-based combinatorial biosynthesis, represent the first l-phenylalanine-based thermolides. Our work shows a unique biosynthetic mechanism of PK-NRP hybrid macrolactones from extremophiles, which led to the discovery of novel compounds and furthers our biosynthetic knowledge.


Asunto(s)
Antinematodos/metabolismo , Lactonas/metabolismo , Péptidos/metabolismo , Policétidos/metabolismo , Talaromyces/metabolismo , Aspergillus nidulans/genética , Ciclización , Escherichia coli/genética , Esterificación
20.
Appl Microbiol Biotechnol ; 104(2): 603-613, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31637495

RESUMEN

Azaphilones are a class of fungal pigments, reported mostly in association with Monascus species. In Asian countries, they are used as food colourants under the name of "red yeast rice" and their production process is well described. One major limitation of current production techniques of azaphilones is that they always occur in a mixture of yellow, orange and red pigments. These mixtures are difficult to control and to quantify. This study has established a controlled and reproducible cultivation protocol to selectively tailor production of individual pigments during a submerged fermentation using another fungal species capable of producing azaphilone pigments, Talaromyces atroroseus, using single amino acids as the sole nitrogen source. The produced azaphilone pigments are called atrorosins and are amino acid derivatives of the known azaphilone pigment Penicillium purpurogenum-orange (PP-O), with the amino acid used as nitrogen source incorporated into the core skeleton of the azaphilone. This strategy was successfully demonstrated using 18 proteinogenic amino acids and the non-proteinogenic amino acid ornithine. Two cultivation methods for production of the pure serine derivative (atrorosin S) have been further developed, with yields of 0.9 g/L being obtained. Yielding pure atrorosins through switching from KNO3 to single amino acids as nitrogen source allows for considerably easier downstream processing and thus further enhances the commercial relevance of azaphilone producing fungal cell factories.


Asunto(s)
Aminoácidos/metabolismo , Medios de Cultivo/química , Pigmentos Biológicos/biosíntesis , Talaromyces/crecimiento & desarrollo , Talaromyces/metabolismo , Benzopiranos , Fermentación , Nitrógeno/metabolismo
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