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1.
J Agric Food Chem ; 67(32): 8875-8883, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31347830

RESUMO

Glucan synthase (GLS) gene is known to be involved in the fungal biosynthesis of cell wall, differentiation, and growth. In the present study, a glucan synthase gene (GFGLS) in the edible mushroom Grifola frondosa with a full sequence of 5927 bp encoding a total of 1781 amino acids was cloned and characterized for the first time. GFGLSp is a membrane protein containing two large transmembrane domains connected with a hydrophilic cytoplasmic domain. With a constructed dual promoter RNA silencing vector pAN7-gfgls-dual, a GFGLS-silencing transformant iGFGLS-3 had the lowest GFGLS transcriptional expression level (26.1%) with a shorter length and thinner appearance of the mycelia, as well as decreased mycelial biomass and exo-polysaccharide production of 5.02 and 0.38 g/L, respectively. Further analysis indicated that GFGLS silence influenced slightly the monosaccharide compositions and ratios of mycelial and exo-polysaccharide. These findings suggest that GFGLS could affect mycelial growth and polysaccharide production by downregulating the glucan synthesis.


Assuntos
Polissacarídeos Fúngicos/biossíntese , Proteínas Fúngicas/metabolismo , Glucosiltransferases/metabolismo , Grifola/enzimologia , Micélio/crescimento & desenvolvimento , Proteínas Fúngicas/genética , Glucosiltransferases/genética , Grifola/genética , Grifola/crescimento & desenvolvimento , Grifola/metabolismo , Micélio/enzimologia , Micélio/genética , Micélio/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo
2.
J Agric Food Chem ; 67(31): 8476-8484, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31298527

RESUMO

Cicada flowers, which are edible and medicinal mushrooms, are the fruiting bodies of Isaria cicadae, a fungus that is parasitic on the larvae of cicada pupae. We hypothesize that host factors might possess stimulatory activity on metabolite synthesis in Isaria cicadae. Here, we first compared the microbial community structures of different wild cicada flowers across geographical regions, compartments, and growth stages via high-throughput sequencing. Isaria cicadae TZC-3, an isolate of the most abundant operational taxonomic unit (OTU6782) in all the fungal communities, was isolated from wild cicada flowers. Furthermore, the effects of cicada pupae on metabolite synthesis in Isaria cicadae TZC-3 were studied in submerged culture. The contents of intercellular polysaccharides, adenosine, N6-(2-hydroxyethyl)-adenosine, free amino acids, and hydrolyzed monosaccharides in the mycelia cultured with cicada pupa powder (4%) were significantly increased as compared with the contents in the control group. This indicates that a cicada pupa can act as an elicitor for metabolite synthesis in Isaria cicadae.


Assuntos
Cordyceps/metabolismo , Carpóforos/química , Hemípteros/microbiologia , Pupa/microbiologia , Adenosina/análise , Adenosina/metabolismo , Aminoácidos/análise , Aminoácidos/metabolismo , Animais , Cordyceps/química , Cordyceps/crescimento & desenvolvimento , Carpóforos/crescimento & desenvolvimento , Carpóforos/metabolismo , Hemípteros/química , Hemípteros/metabolismo , Interações Hospedeiro-Patógeno , Microbiota , Micélio/química , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Pupa/química , Pupa/metabolismo
3.
Sheng Wu Gong Cheng Xue Bao ; 35(5): 749-758, 2019 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-31222993

RESUMO

Filamentous fungi are one of the platforms for producing fermented products. The specific characteristic of their submerged fermentation is the aggregation of mycelia that is affected by environmental conditions, leading to significantly different rheology for fermentation broth. Such a rheological change not only affects the transfer of mass, heat and momentum, but also the biosynthesis of target products and the efficiency of their production. In this article, strategies for morphological regulation of filamentous fungi are reviewed, and the impact of calcium signal transduction and chitin biosynthesis on apical growth of hyphae and branching of mycelia for their aggregation are further commented.


Assuntos
Fermentação , Fungos , Micélio , Fungos/fisiologia , Temperatura Alta , Micélio/metabolismo , Reologia
4.
Int J Mol Sci ; 20(9)2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31083449

RESUMO

To clarify the physiological mechanism of the Lentinula edodes (L. edodes) response to high-temperature stress, two strains of L. edodes with different tolerances were tested at different durations of high temperature, and the results showed that there were significant changes in their phenotypes and physiology. To further explore the response mechanism, we established a targeted GC-MS-based metabolomics workflow comprising a standardized experimental setup for growth, treatment and sampling of L. edodes mycelia, and subsequent GC-MS analysis followed by data processing and evaluation of quality control (QC) measures using tailored statistical and bioinformatic tools. This study identified changes in the L. edodes mycelial metabolome following different time treatments at high temperature based on nontargeted metabolites with GC-MS and further adopted targeted metabolomics to verify the results of the analysis. After multiple statistical analyses were carried out using SIMCA software, 74 and 108 differential metabolites were obtained, respectively. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the metabolic pathways with significant changes included those related to the following: amino acid metabolism, the glycolysis pathway, the tricarboxylic acid (TCA) cycle, and sugar metabolism. Most amino acids and carbohydrates enriched in these metabolic pathways were upregulated in strain 18, downregulated in strain 18N44, or the synthesis in strain 18 was higher than that in strain 18N44. This result was consistent with the physiological phenotypic characteristics of the two strains under high-temperature stress and revealed the reason why strain 18N44 was more heat-sensitive. At the same time, under high temperature, the decrease of intermediate products in glycolysis and the TCA cycle resulted in carbon starvation and insufficient energy metabolism, thus inhibiting the growth of L. edodes. In addition, the results also showed that the metabolites produced by different L. edodes strains under high-temperature stress were basically the same. However, different strains had species specificity, so the changes in the content of metabolites involved in the response to high-temperature stress were different. This provides a theoretical basis for further understanding the mechanism of the L. edodes response to high temperature and can be used to establish an evaluation system of high-temperature-resistant strains and lay the foundation for molecular breeding of new L. edodes strains resistant to high temperature.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Temperatura Alta , Metaboloma , Metabolômica , Micélio/metabolismo , Cogumelos Shiitake/metabolismo , Estresse Fisiológico , Micélio/crescimento & desenvolvimento , Reprodutibilidade dos Testes , Cogumelos Shiitake/crescimento & desenvolvimento
5.
Environ Sci Pollut Res Int ; 26(20): 20418-20427, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31098914

RESUMO

Ectomycorrhizal fungi can enhance the tolerance of plants to heavy metal stress by reducing the accumulation of heavy metals in the aerial parts of the plants. Extracellular chelation is a major mechanism of heavy metal tolerance in ectomycorrhizal fungi in which extracellular slime plays a fundamental role. The objectives of this study were to investigate the potential metal-binding ability and the protein composition of extracellular slime. The extracellular slime of Laccaria bicolor (L. bicolor) cultivated under Cd2+ and Cu2+ stress was separated using various ultrasonic pre-treatments. The protein content, composition, and metal content of the extracellular slime were measured. The results showed that the protein content in the extracellular slime significantly increased under both Cd2+ and Cu2+ stress. The SDS-PAGE profile showed that Cd2+ and Cu2+ stress induced the expression of several new proteins. Heavy metal quantification revealed that the Cd content fixed in the extracellular slime accounted for 22-28% of the metal fixed by the fungal mycelia. Meanwhile, no Cu was detected in the fungal extracellular slime, implying that the extracellular slime may not be effective for the fixation of essential metallic elements such as Cu. Taken together, these results provided evidence that L. bicolor was able to ameliorate the intracellular Cd content by stimulating extracellular slime exudation and altering the composition of the proteins therein. Nevertheless, this blocking strategy may be effective only for the non-essential element Cd and was ineffective for the physiological element Cu.


Assuntos
Cádmio/metabolismo , Cobre/metabolismo , Proteínas Fúngicas/metabolismo , Laccaria/efeitos dos fármacos , Laccaria/metabolismo , Cádmio/toxicidade , Cobre/toxicidade , Farmacorresistência Fúngica , Eletroforese em Gel de Poliacrilamida , Matriz Extracelular/metabolismo , Micélio/metabolismo
6.
J Basic Microbiol ; 59(6): 609-620, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30980724

RESUMO

Revegetation is widely used to enhance degraded topsoil recovery with the enhancements of soil nutrient accumulation and soil structure stabilization. Arbuscular mycorrhizal fungi (AMF) are important for the allocation of carbon into the soil and the formation of soil aggregates. Thus, we hypothesized that AMF could construct more niches for other microbes during revegetation, making AMF keystone taxa of soil. Soil fungal and bacterial communities were investigated under a revegetation experiment and correlation networks between soil fungi and bacteria were constructed. Simultaneously, the plant growth level, soil properties and structure, and soil microbial carbon decomposition abilities were measured. The results revealed that AMF were the most central fungi at the phylum (degree = 3), class (degree = 11), and family (degree = 15) levels. The reads number of AMF were positively correlated with both fungal (R2 = 0.431, P < 0.001) and bacterial (R2 = 0.106, P = 0.044) richness. Higher colonization of AMF in roots and/or more AMF extraradical mycelium and spores in soil indicated a better plant growth, more stable soil aggregates, and a higher carbon decomposition ratio. Our results highlight that AMF are keystone taxa in revegetation, as they play significant roles in enhancing the recovery of the belowground microbiome diversity, soil structure stability, and nutrients cycling. The positive roles of AMF in revegetation support the application of AMF in ecosystem recovery.


Assuntos
Recuperação e Remediação Ambiental , Microbiota , Micorrizas/fisiologia , Microbiologia do Solo , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Carbono/metabolismo , Fungos/classificação , Fungos/genética , Fungos/crescimento & desenvolvimento , Fungos/metabolismo , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Micorrizas/classificação , Micorrizas/crescimento & desenvolvimento , Micorrizas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Poaceae/crescimento & desenvolvimento , Poaceae/microbiologia , Solo/química , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/metabolismo , Tibet
7.
J Appl Microbiol ; 127(1): 175-185, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30980449

RESUMO

AIMS: This study aimed to compare the effects of cold plasma (CP), ultraviolet (UV-C) and aqueous ozone (AO) on Botrytis cinerea and explore their application in preserving blueberry. METHODS AND RESULTS: The effects of CP, UV-C or AO on B. cinerea were investigated. Results showed that three treatments effectively inhibited the growth of B. cinerea, increasing cell membrane penetrability and causing the leakage of cytoplasm and nucleic acid. Scanning electron microscopy showed that CP caused the mycelium fold and collapse depression; UV-C caused the mycelium shrivelled; mycelium treated with AO appeared to fold and break. In the in vivo test in blueberry, all treatments effectively inhibited the growth of micro-organisms, maintained qualities and enhanced antioxidant activities in blueberry during postharvest storage. CONCLUSION: Cold plasma, UV-C and AO effectively inhibited the growth of B. cinerea and significantly extended the shelf life of blueberry. Based on in vitro and in vivo tests, CP showed better effects to preserve blueberry compared with other treatments. SIGNIFICANCE AND IMPACT OF THE STUDY: Our findings revealed the effective mechanisms of CP, UV-C and AO to inhibit B. cinerea in vitro. CP exhibited better application potential to preserve fresh fruit than traditional sterilization methods such as UV-C and AO.


Assuntos
Mirtilos Azuis (Planta) , Botrytis/efeitos dos fármacos , Botrytis/efeitos da radiação , Microbiologia de Alimentos , Conservação de Alimentos/métodos , Frutas/microbiologia , Raios Ultravioleta , Botrytis/crescimento & desenvolvimento , Botrytis/metabolismo , Qualidade dos Alimentos , Frutas/fisiologia , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Micélio/efeitos da radiação , Ozônio/farmacologia , Gases em Plasma/farmacologia
8.
Int J Med Mushrooms ; 21(4): 311-322, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31002627

RESUMO

The optimization of microbial growth for biotechnological purposes traditionally requires an approach that uses only one variable at a time, which has many drawbacks. This research used a completely randomized approach to optimize carbon and nitrogen nutrient requirements and growth factors (pH and temperature) for Pleurotus tuber-regium in order to optimally produce biomass and extracellular polysaccharide (EPS) in shake-flask cultures. An artificial neural network (ANN) module was used to simulate the fungus-growing process and hence determine optimal conditions. The experiments demonstrated the effectiveness of the EPS fraction from P. tuber-regium in preserving hepatic cells against paracetamol-induced damage. Totals of 0.699 g biomass and 0.291 g EPS per 100 mL medium were obtained, whereas the ANN predicted 0.750 g biomass and 0.300 g EPS per 100 mL medium, thereby achieving 93.20% predictability for biomass and 73.00% predictability for EPS. Conditions for optimal EPS and biomass production for P. tuber-regium were quite different. Rat hepatic cells that had been fortified with the EPS fraction from P. tuber-regium were effectively preserved against liver damage. By using a mathematical approach, this study established optimal fermentation conditions for mycelia biomass and EPS production by P. tuber-regium and the relevant biotechnological implications.


Assuntos
Fermentação , Pleurotus/crescimento & desenvolvimento , Polissacarídeos/metabolismo , Acetaminofen/efeitos adversos , Animais , Biomassa , Carbono/metabolismo , Hepatócitos/efeitos dos fármacos , Modelos Teóricos , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Nitrogênio/metabolismo , Pleurotus/metabolismo , Polissacarídeos/farmacologia , Ratos
9.
Mar Biotechnol (NY) ; 21(3): 430-439, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30895403

RESUMO

This study describes the chemoselective hydrogenation reaction of halogenated 2'-hydroxychalcones by the marine-derived fungus Penicillium raistrickii CBMAI 931. Initially, 2'-hydroxychalcone was utilized as a model for the selection of the appropriate conditions to perform the biotransformation reactions. The best results were obtained using mycelia and filtered culture broth, and this condition was chosen for the biotransformation reaction of 2'-hydroxychalcones substituted with methoxy and halogen groups. Experiments performed with 2'-hydroxychalcones dissolved in 600 µL-DMSO were more effective than those performed using 300 µL-DMSO, once solubility of the compounds influenced conversion rate in the liquid medium. The halogenated 2'-hydroxy-dihydrochalcones were obtained in good conversions (78-99%) and moderate isolated yields (31-65%). All biotransformation reactions using the marine-derived fungus P. raistrickii CBMAI 931 showed regioselective and chemoselective control for the formation of 2'-hydroxy-dihydrochalcones.


Assuntos
Biotransformação , Chalconas/metabolismo , Micélio/metabolismo , Penicillium/metabolismo , Halogenação , Hidrogenação
10.
Bioengineered ; 10(1): 13-22, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30836830

RESUMO

The deep-sea bacterium strain FA13 was isolated from the sediment of the South Atlantic Ocean and identified as Bacillus circulans based on 16S ribosomal DNA sequence. Through liquid fermentation with five media, the cell-free supernatant fermented with ISP2 showed the highest inhibition activities against mycelial growth of Aspergillus parasiticus mutant strain NFRI-95 and accumulation of norsolorinic acid, a precursor for aflatoxin production. Based on ISP2, uniform design was used to optimize medium formula and fermentation conditions. After optimization, the inhibition efficacy of the 20-time diluted supernatant against A. parasiticus NFRI-95 mycelial growth and aflatoxin production was increased from 0-23.1% to 100%. Moreover, compared to the original protocol, medium cost and fermentation temperature were significantly reduced, and dependence on seawater was completely relieved, thus preventing the fermentor from corrosion. This is the first report of a deep-sea microorganism which can inhibit A. parasiticus NFRI-95 mycelial growth and aflatoxin production.


Assuntos
Aflatoxinas/antagonistas & inibidores , Antraquinonas/antagonistas & inibidores , Antitoxinas/isolamento & purificação , Aspergillus/efeitos dos fármacos , Bacillus/metabolismo , Micélio/efeitos dos fármacos , Aflatoxinas/biossíntese , Antraquinonas/metabolismo , Antitoxinas/farmacologia , Organismos Aquáticos , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Aspergillus/patogenicidade , Oceano Atlântico , Bacillus/classificação , Bacillus/genética , Bacillus/isolamento & purificação , Reatores Biológicos , Meios de Cultura/química , Análise Fatorial , Fermentação , Sedimentos Geológicos/microbiologia , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Micélio/patogenicidade , Filogenia , RNA Ribossômico 16S/genética , Temperatura Ambiente
11.
Int J Biol Macromol ; 130: 307-314, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30825564

RESUMO

A comparison of the anti-tumor activity of CMPS-II and CBPS-II polysaccharides, respectively is obtained from the fermented mycelium and cultivated fruiting bodies of Cordyceps militaris. This in vitro anti-tumor activity is investigated using an MTT assay, immunofluorescence staining, a Western Blot assay, a qRT-PCR assay, and Annexin V-FITC/PI double staining. The experimental results indicate that the inhibition rate of CMPS-II on H1299 tumor cells is higher than that of CBPS-II. With a concentration of 500 µâ€¯g/mL, the inhibition rate of CMPS-II and CBPS-II were 54.55% and 34.80%, respectively. Both CMPS-II and CBPS-II can increase the protein and mRNA expression level of cell apoptosis factors Caspase-3, Caspase-9, and p53, while reducing the protein and mRNA expression levels of proliferating cell nuclear antigen (PCNA), to induce tumor cells apoptosis. The induction effect of CMPS-II was stronger than CBPS-II. These results suggest that CMPS-II is superior to CBPS-II regarding the inhibition of H1299 lung cancer cells. Furthermore, CMPS-II is a potentially useful substitution for CBPS-II in the treatment of lung cancer and provides new insights into the mechanism of its anti-tumor activity.


Assuntos
Antineoplásicos/farmacologia , Cordyceps/metabolismo , Fermentação , Carpóforos/metabolismo , Polissacarídeos Fúngicos/farmacologia , Micélio/metabolismo , Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Caspase 9/genética , Caspase 9/metabolismo , Linhagem Celular Tumoral , Polissacarídeos Fúngicos/biossíntese , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
12.
Water Environ Res ; 91(2): 93-100, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30735302

RESUMO

Mycelial pellets, as a novel biomass material, can adsorb pollutants as a biosorbent, or combine other substances and organisms to form self-immobilized biomixture (SIB) to remove pollutants from wastewater. The pellets are eco-friendly, have a good self-immobilization capacity, and are easy to filter. In addition, some mycelial fungi can remove the pollutants in water through biodegradation. This study reviewed biomixture based on mycelial pellets and the two ways, through which SIB remove pollutants in water: pure pellets and the pellets with other materials. The characteristics and functions of each part of SIB were discussed. The study also highlighted the shortcomings of the technology and provided recommendations for further development of this technology.


Assuntos
Biomassa , Micélio/metabolismo , Águas Residuárias/química , Purificação da Água/métodos , Águas Residuárias/microbiologia
13.
Antonie Van Leeuwenhoek ; 112(7): 1095-1104, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30725325

RESUMO

Rubber anthracnose caused by Colletotrichum gloeosporioides leads to huge economic loss in the natural rubber industry every year. Conidia of C. gloeosporioides are a major infection source but little is known about molecular mechanisms underlying conidial development and infection. In this study, the C. gloeosporioide C2H2 zinc-finger protein transcription factor gene CgAzf1 is shown to be involved in melanin production, conidial development and infection. Deletion of CgAzf1 resulted in decreased melanin production and hydrophilicity of aerial mycelium was increased. The mutants also showed reduced conidiation, low germination rate, and the formation of appressorium lagged too. Virulence assays showed that the CgAzf1 deletion strain could not infect intact rubber tree leaves and had an attenuated virulence on the wounded leaves. Quantitative RT-PCR showed that CgAzf1 regulates expression of genes involved in the MAPK, cAMP-PKA and melanin biosynthesis pathways.


Assuntos
Colletotrichum/metabolismo , Colletotrichum/patogenicidade , Proteínas Fúngicas/metabolismo , Hevea/microbiologia , Melaninas/metabolismo , Doenças das Plantas/microbiologia , Esporos Fúngicos/crescimento & desenvolvimento , Fatores de Transcrição/metabolismo , Colletotrichum/genética , Colletotrichum/crescimento & desenvolvimento , Proteínas Fúngicas/genética , Micélio/química , Micélio/genética , Micélio/metabolismo , Micélio/patogenicidade , Filogenia , Esporos Fúngicos/genética , Esporos Fúngicos/metabolismo , Esporos Fúngicos/patogenicidade , Fatores de Transcrição/genética , Virulência
14.
BMC Genomics ; 20(1): 121, 2019 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-30736734

RESUMO

BACKGROUND: Lentinula edodes is one of the most popular edible mushroom species in the world and contains useful medicinal components, such as lentinan. The light-induced formation of brown film on the vegetative mycelial tissues of L. edodes is an important process for ensuring the quantity and quality of this edible mushroom. To understand the molecular mechanisms underlying this critical developmental process in L. edodes, we characterized the morphological phenotypic changes in a strain, Chamaram, associated with abnormal brown film formation and compared its genome-wide transcriptional features. RESULTS: In the present study, we performed genome-wide transcriptome analyses of different vegetative mycelium growth phenotypes, namely, early white, normal brown, and defective dark yellow partial brown films phenotypes which were exposed to different light conditions. The analysis revealed the identification of clusters of genes specific to the light-induced brown film phenotypes. These genes were significantly associated with light sensing via photoreceptors such as FMN- and FAD-bindings, signal transduction by kinases and GPCRs, melanogenesis via activation of tyrosinases, and cell wall degradation by glucanases, chitinases, and laccases, which suggests these processes are involved in the formation of mycelial browning in L. edodes. Interestingly, hydrophobin genes such as SC1 and SC3 exhibited divergent expression levels in the normal and abnormal brown mycelial films, indicating the ability of these genes to act in fruiting body initiation and formation of dikaryotic mycelia. Furthermore, we identified the up-regulation of glycoside hydrolase domain-containing genes in the normal brown film but not in the abnormal film phenotype, suggesting that cell wall degradation in the normal brown film phenotype is crucial in the developmental processes related to the initiation and formation of fruiting bodies. CONCLUSIONS: This study systematically analysed the expression patterns of light-induced browning-related genes in L. edodes. Our findings provide information for further investigations of browning formation mechanisms in L. edodes and a foundation for future L. edodes breeding.


Assuntos
Perfilação da Expressão Gênica , Lentinula/genética , Lentinula/metabolismo , Micélio/genética , Micélio/metabolismo , Pigmentação/genética , Genes Fúngicos/genética , Lentinula/efeitos da radiação , Luz , Micélio/efeitos da radiação , Fenótipo , Pigmentação/efeitos da radiação
15.
Curr Microbiol ; 76(3): 263-269, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30607505

RESUMO

White-rot fungi are microorganisms capable of ethanol fermentation; however, the specific conditions activating ethanol fermentation are unclear in contrast to fermentation by yeasts. In this study, we investigated the conditions favoring ethanol fermentation by the white-rot fungus Phanerochaete sordida YK-624, which is able to produce ethanol from woody material. In aerobic stationary cultivation with various concentrations of glucose (0.8-33 g/l), the fungus produced ethanol in media containing an initial glucose concentration of 2.8 g/l or higher. The amount of glucose consumption, mycelial weight, and ethanol production on the second day of culture increased in a concentration-dependent manner at low glucose concentrations; however, these were saturated at high concentrations. Biomass yields (growth/glucose consumption) were decreased until the initial glucose concentration increased to 6.0 g/l, after which the biomass yields showed constant values at higher concentrations (12-33 g/l). On the other hand, ethanol yields increased with decreasing biomass yields. In short shaking cultivation using mycelial suspension, trace amounts of instantaneous aerobic ethanol production were observed with 1.1 and 2.1 g/l glucose, but the relative gene expression levels of key enzymes at the pyruvate branch point showed no significant differences between ethanol production and non-production conditions. From these experimental results, it appears that the white-rot fungus P. sordida YK-624 produces ethanol due to overflow in sugar metabolism under aerobic conditions, although P. sordida YK-624 prioritizes glucose utilization for respiratory growth.


Assuntos
Etanol/metabolismo , Glucose/metabolismo , Phanerochaete/metabolismo , Aerobiose , Biomassa , Reatores Biológicos , Metabolismo dos Carboidratos , Meios de Cultura/química , Fermentação , Glucose/química , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Phanerochaete/crescimento & desenvolvimento
16.
J Biosci Bioeng ; 128(1): 1-7, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30683592

RESUMO

Tyrosinase is an industrially useful enzyme, however, it causes gill browning of Lentinula edodes fruiting bodies during preservation. In this study, we constructed two vectors, pChG-gTs and pChG-gTa, expressing sense and antisense tyrosinase gene of L. edodes, respectively, using promoters derived from the glyceraldehyde-3-phosphate dehydrogenase gene. The host strain SR-1 of L. edodes was selected because of its fast growth, high protoplast yield, and high regeneration rate. Upon transformation of the host strain SR-1 with the pChG-gTs vector, a clone with 3.6-fold and 14.5-fold higher tyrosinase activity in vegetative mycelia and in fresh gills, respectively, than that of the host strain was obtained from nine transformants. Similarly, two clones containing the pChG-gTa vector with effectively repressed tyrosinase gene expression in vegetative mycelia and gills during the late stage of post-harvest preservation of fruiting bodies were obtained from 10 transformants. However, it remained unclear whether repression of the tyrosinase gene prevented gill browning, as the host strain also showed less browning than a commercial strain. Thus, this study highlights the usefulness of the pChG vector in expressing homologous enzyme coding genes in the vegetative mycelia and fruiting bodies of L. edodes.


Assuntos
Quitina Sintase/genética , Vetores Genéticos/genética , Monofenol Mono-Oxigenase/genética , Regiões Promotoras Genéticas/genética , Cogumelos Shiitake/genética , Transformação Genética , Carpóforos/genética , Carpóforos/crescimento & desenvolvimento , Carpóforos/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Inativação Gênica/fisiologia , Monofenol Mono-Oxigenase/metabolismo , Micélio/genética , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Organismos Geneticamente Modificados , Cogumelos Shiitake/enzimologia , Cogumelos Shiitake/crescimento & desenvolvimento , Transformação Genética/genética , Regulação para Cima/genética
17.
Int J Biol Macromol ; 125: 572-579, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30543884

RESUMO

EP-1 is a polysaccharide with a molecular weight of approximately 3100 Da, which is extracted from the cultured mycelium of Hericium erinaceus. Its anti-ulcerative colitis activity was evaluated in experimental systems using rats with ulcerative colitis and Caco-2 cells as models for experimentation. Our results showed that the treatment of EP-1 could increase SOD enzyme activity as well as decrease ROS content and oxidative damage both in vivo and in vitro. As a consequence, mitochondria function improved significantly, indicated by the increase of oxygen consumption and ATP production. In addition, increased respiration activity accelerated the elimination of excessive ROS substrate and enhanced bioenergy generation. Finally, upon treatment with EP-1, apoptosis of intestinal epithelial cells was reduced and UC was relieved accordingly. Thus, EP-1 shows potential for the development of new functional foods and drugs, especially in regard to treating ulcerative colitis.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Micélio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Células CACO-2 , Linhagem Celular Tumoral , Colite Ulcerativa/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Humanos , Masculino , Camundongos , Mitocôndrias/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
18.
Biomed Chromatogr ; 33(4): e4478, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30578653

RESUMO

Isaria cicadae is one of the fungi used in traditional Chinese medicine with the longest tradition. It is used not only as a herbal medicine but also as a health food in Asia, together with cultured cordyceps and mycelia of the fungus used as substitute. However, the differences in their metabolite are unknown. Using a high-performance liquid chromatography-mass spectrometry (HPLC-MS)-based metabolomic method, we found that the fungus varies in its metabolism during growth on wild insects, artificially raised insects and artificial medium. There were 109 discriminatory metabolites detected in the samples by orthogonal projection to latent structure discriminant analysis and one-way ANOVA. High level of nonribosomal peptides (NRPs) only existed in the insect portions of the wild cordyceps (WI) and cultured cordyceps (CI), revealing that immunostimulation of the host insects enhanced the synthesis of NRPs in the fungus. The finding of a significantly higher level of sphingolipids in both the insect portions (WI, CI) and the coremia of the wild cordyceps (WC) and cultured cordyceps (CC) but not in cultured mycelia (CM) of I. cicadae implies that the immunostimulation of the live insects can induce the fungus to produce more sphingolipids, and this enhanced ability is probably heritable. Apart from NRPs and sphingolipids, the insect portions also contained higher levels of bioactive compounds such as lateritin, anisomycin, streptimidone and ustiloxins. In contrast, the coremium groups (WC, CC) and CM contained 10-fold less NRP but much higher levels of sanative metabolites such as tocotrienol, 3'-deoxy-hanasanagin, γ-aminobutyric acid and phospholipids than the insect portions. The significantly higher content of antioxidants in WC, CC and CM than in WI and CI suggests that environmental oxygen has a significant effect on the metabolites. The temperature stress which the wild cordyceps encounters during growth is responsible for the relatively high content of trehalose. These findings indicate that the immunity of the host insect and growth environment have a strong impact on the metabolomic variation in Isaria cicadae. The variation in metabolites suggests differential utilization value for the insect portions, coremia and mycelia of the fungus.


Assuntos
Cordyceps/química , Cordyceps/metabolismo , Metaboloma/fisiologia , Metabolômica/métodos , Micélio/química , Micélio/metabolismo , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Cordyceps/classificação , Espectrometria de Massas , Análise de Componente Principal , Reprodutibilidade dos Testes
19.
Biochim Biophys Acta Biomembr ; 1861(1): 316-326, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29908139

RESUMO

Metarhizium robertsii, a butyltin-resistant filamentous fungus, can rapid and complete biodegradation of di- (DBT) and tributyltin (TBT) under conditions of intensive aeration and ascorbic acid supplementation. In this paper, lipidomic investigations were performed to find the membrane adaptations necessary for effective butyltins degradation. HPLC-MS/MS analysis showed that the phospholipid profile was greatly modified during M. robertsii batch cultivation (pO2 ≥ 20%), contributing to increased membrane fluidity and facilitated mass transfer, which could enhance butyltins biodegradation. Intensified biosynthesis of phospholipids, sphingolipids and ergosterol by the mycelia exposed to butyltins was noted. DIOC6(3) fluorescence intensity for TBT-treated mycelium increased 9-fold pointing to membrane hyperpolarization. Fluorescent studies showed improved membrane rigidity and integrity in response to butyltins presence. Vitamin C supplementation restored membrane composition and dynamic properties, followed by supposed acceleration of transport of monobutyltin and its biodegradation thus protecting the M. robertsii cells against oxidative and nitrosative stress.


Assuntos
Metarhizium/metabolismo , Compostos Orgânicos de Estanho/farmacologia , Compostos de Trialquitina/farmacologia , Adaptação Fisiológica , Ácido Ascórbico/farmacologia , Biodegradação Ambiental , Suplementos Nutricionais , Ergosterol/metabolismo , Bicamadas Lipídicas/metabolismo , Metarhizium/efeitos dos fármacos , Micélio/metabolismo , Estresse Nitrosativo , Oxirredução , Estresse Oxidativo , Fosfolipídeos/metabolismo , Esfingolipídeos/metabolismo , Propriedades de Superfície , Espectrometria de Massas em Tandem
20.
Biosci Biotechnol Biochem ; 83(4): 774-780, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30585121

RESUMO

Cyclooxygenases are responsible for the production of prostaglandin H2 (PGH2) from arachidonic acid. PGH2 can be converted into some bioactive prostaglandins, including prostaglandin F2α (PGF2α), a potent chemical messenger used as a biological regulator in the fields of obstetrics and gynecology. The chemical messenger PGF2α has been industrially produced by chemical synthesis. To develop a biotechnological process, in which PGF2α can be produced by a microorganism, we transformed an oleaginous fungus, Mortierella alpina 1S-4, rich in triacylglycerol consisting of arachidonic acid using a cyclooxygenase gene from a red alga, Gracilaria vermiculophylla. PGF2α was accumulated not only in the mycelia of the transformants but also in the extracellular medium. After 12 days of cultivation approximately 860 ng/g and 6421 µg/L of PGF2α were accumulated in mycelia and the extracellular medium, respectively. The results could facilitate the development of novel fermentative methods for the production of prostanoids using an oleaginous fungus.


Assuntos
Proteínas de Algas/genética , Ácido Araquidônico/metabolismo , Dinoprosta/biossíntese , Gracilaria/química , Engenharia Metabólica/métodos , Mortierella/genética , Prostaglandina-Endoperóxido Sintases/genética , Agrobacterium tumefaciens/genética , Agrobacterium tumefaciens/metabolismo , Proteínas de Algas/metabolismo , Meios de Cultura/química , Expressão Gênica , Gracilaria/genética , Hidroxiprostaglandina Desidrogenases/genética , Hidroxiprostaglandina Desidrogenases/metabolismo , Mortierella/metabolismo , Micélio/genética , Micélio/metabolismo , Plasmídeos/química , Plasmídeos/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Transformação Genética , Transgenes
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