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1.
Artigo em Inglês | MEDLINE | ID: mdl-32406803

RESUMO

The ability of white-rot fungus, Trametes hirsuta AK04, to utilize phenolics as single and mixed substrates was determined in mineral medium and palm oil mill effluent (POME). The strain AK04 was able to rapidly metabolize all ten phenolics as single and mixed substrates at all test concentrations. With single substrates, between 78 and 98% removal was achieved within seven days. The biomass yield increased with increasing concentration from 100 to 500 mg L-1 but slightly decreased when the concentration was increased up to 1,000 mg L-1. When fitted to a Haldane model, the groups of benzoic and cinnamic acid derivatives gave significantly higher maximum specific growth rates than other phenolics. Phenol exhibited the lowest affinity and highest inhibitory effects on fungal metabolism. In mixed substrates, the total concentration ranges of phenolics mixtures between 1,000 and 6,000 mg L-1 did not affect the fungal growth rate and the strain AK04 showed a high degree of resistance to their toxic effects. The addition of glucose and yeast extract enhanced the degradation rates of individual phenolics in the substrate mixtures, demonstrating the advantage of this strain for treating complex media, such as industrial wastewater.


Assuntos
Resíduos Industriais/análise , Óleo de Palmeira , Fenóis/metabolismo , Trametes/crescimento & desenvolvimento , Águas Residuárias/química , Poluentes Químicos da Água/análise , Biodegradação Ambiental , Biomassa , Cinética , Modelos Teóricos , Fenóis/análise , Tailândia , Trametes/metabolismo , Purificação da Água/métodos
2.
Fungal Biol ; 123(12): 913-926, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31733734

RESUMO

Trametes ljubarskyi produces multiple laccase isozymes under various physicochemical conditions. During co-cultivation condition Rhodotorula mucilaginosa showed inter-specific interactions with T. ljubarskyi and hypersecretion of laccases; however, the underlying molecular mechanism is less-known. The analysis of proteomics data of co-cultivated cultures revealed the mechanism of metabolic coupling during fungal-yeast interactions. The results suggested high score GO terms related to stimulus-response, protein binding, membrane components, transport channels, oxidoreductases, and antioxidants. The SEM studies confirmed the cellular communication and their inter-specific interactions. This study allows us to deepen and refine our understanding of fungal-yeast symbiotic interaction; further, it also establishes a mutual relation by metabolic coupling for 10-fold higher laccase isozyme secretion (6532 U/ml). The purified laccase isozymes showed acidic pH optima (pH 3-4), higher thermo-stability (60 °C), and broad enzyme kinetics (Km) values. Our study also provides an in-depth understanding of laccase isozymes and their potential to degrade synthetic dyes, which may help the fungi to survive in an adverse environment.


Assuntos
Isoenzimas/metabolismo , Lacase/metabolismo , Interações Microbianas , Rhodotorula/crescimento & desenvolvimento , Rhodotorula/metabolismo , Trametes/crescimento & desenvolvimento , Trametes/metabolismo , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Proteômica , Rhodotorula/citologia , Rhodotorula/enzimologia , Temperatura , Trametes/citologia , Trametes/enzimologia
3.
Int J Med Mushrooms ; 21(8): 735-753, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679282

RESUMO

Basidiomycetes of various species and their wide range of pharmaceuticaly interesting products in the past decades represents one of the most attractive groups of natural products in Asia and North America. Production of mushroom fruit bodies using farming technology is hardly covering the market. Development of comprehensive submerged technologies in stirred tank and air lift bioreactors are the most promising technologies for fast and large-amount cultivation of medicinal mushroom biomass and its pharmaceutically active products. Research in physiology, basic and applied studies in mushroom metabolism, process engineering aspects, and clinical studies in the past two decades represent a large cotribution to the development of this potential, which initiates the development of new drugs and some very attractive over-the-counter human and veterinary remedies. The current article is an overview of the most relevant engineering achievements in submerged cultivation of some medicinal mushrooms-Grifola frondosa, Trametes versicolor, Hericium erinaceus, and Cordyceps militaris-and some other species biomass production in bioreactors.


Assuntos
Basidiomycota/crescimento & desenvolvimento , Produtos Biológicos/metabolismo , Reatores Biológicos , Agaricales , Agricultura , Ásia , Basidiomycota/metabolismo , Biomassa , Cordyceps/crescimento & desenvolvimento , Cordyceps/metabolismo , Engenharia , Grifola/crescimento & desenvolvimento , Grifola/metabolismo , Trametes/crescimento & desenvolvimento , Trametes/metabolismo
4.
Int J Med Mushrooms ; 21(11): 1115-1122, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32450021

RESUMO

Mono- and dikaryotic medicinal mushroom strains isolated from four wood-rotting basidiomycete fruiting bodies were comparatively evaluated for laccase, manganese peroxidase, cellulase, and xylanase activities in submerged cultivation in glucose or mandarin peel-containing media. Mandarin peels appeared to be the preferred growth substrate for laccase production by both mono- and dikaryotic Trametes multicolor 511 and T. versicolor 5 while glucose favored laccase activity secretion by Pleurotus ostreatus 2175. Lignocellulose-deconstructing enzyme profiles were highly variable between the studied monokaryotic and dikaryotic strains. A distinctive superiority of enzyme activity of the dikaryotic Trametes versicolor 5 and P. ostreatus 2175 over the same species monokaryotic isolates was revealed. By contrast, laccase, cellulase, and xylanase activities of the monokaryotic strain of T. multicolor 511 were rather higher than those in the dikaryotic culture. At the same time, hydrolases activity of Schizophyllum commune 632 was practically independent of the origin of the fungal culture. The results suggest that the monokaryotic isolates derived from the basidiomycetes fruiting bodies inherit parental properties but the capacity of individual monokaryotic cultures to produce lignocellulose-deconstructing enzymes can vary considerably.


Assuntos
Celulases/metabolismo , Lacase/metabolismo , Lignina/metabolismo , Peroxidases/metabolismo , Pleurotus/enzimologia , Schizophyllum/enzimologia , Trametes/enzimologia , Xilosidases/metabolismo , Meios de Cultura/química , Carpóforos/enzimologia , Pleurotus/crescimento & desenvolvimento , Schizophyllum/crescimento & desenvolvimento , Trametes/crescimento & desenvolvimento
5.
Bioprocess Biosyst Eng ; 41(7): 1017-1028, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29616333

RESUMO

The potential to produce ethanol and xylitol from xylose by the macro basidiomycete Trametes membranacea was evaluated. All strains studied showed ethanol and xylitol production. The highest ethanol production of xylose was obtained by T. membranacea strain TM158/10 with 5.65 ± 0.21 g/L at pH 4 and 28 °C with 288 h of fermentation and 5.59 ± 0.05 g/L ethanol concentration at pH 5 and 24 °C with 360 h of fermentation. When the conversion was carried out using sugars generated from enzymatic hydrolysis of sugarcane bagasse, there were higher yields from 74 to 15% for ethanol and xylitol, respectively. Although the ethanol and xylitol production need to be optimized, this study showed for the first time the possibility of using T. membranacea for the simultaneous xylitol and ethanol production from pentose sugars, allowing for the possibility of using all released sugars during the hydrolysis of lignocelluloses.


Assuntos
Celulose/química , Etanol/metabolismo , Saccharum/química , Trametes/crescimento & desenvolvimento , Xilitol/biossíntese
6.
Fungal Biol ; 122(5): 353-362, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29665961

RESUMO

Laccase (benzenediol:oxygen oxidoreductase, EC 1.10.3.2) is an enzyme that has been studied for over 100 y and is present in virtually all fungi. As increasing numbers of fungal genomes have been sequenced, it has become apparent that the laccase genes in white-rot fungi commonly form multigene families consisting of many nonallelic genes. Although a number of reports focussing on laccase gene expression in different fungal species were published over the decades, the fundamental questions of why fungi need such a redundant array of genes and how they manage this array to perform biological function(s) remain far from answered. In this article, we present a comprehensive study of the transcription of the whole Trametes hirsuta laccase multigene family under different conditions, including exposure to different nutritional factors such as nitrogen sources (organic and inorganic) and concentrations of nitrogen and carbon in the culture medium; in different growth phases (lag phase and stationary phase); and in the presence of different inducer agents (water-soluble lignin, bromocresol green dye, p-coumaric acid, ferulic acid, guaiacol, vanillin, veratryl alcohol, vanillic acid and syringic acid). Our findings are discussed in the context of the evolution of the laccase multigene family, and the presence of transcription-level subfunctionalization is highlighted.


Assuntos
Regulação Fúngica da Expressão Gênica , Lacase/biossíntese , Trametes/enzimologia , Trametes/genética , Transcrição Gênica , Carbono/metabolismo , Meios de Cultura/química , Ativadores de Enzimas/metabolismo , Lacase/genética , Família Multigênica , Compostos de Nitrogênio/metabolismo , Trametes/crescimento & desenvolvimento , Trametes/metabolismo
7.
Chemosphere ; 198: 198-203, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29421730

RESUMO

The disposal of agricultural antibiotic-containing wastewater in biopurification systems (BPS) employed in the treatment of pesticides, may negatively affect the removal capacity of these devices. This work aimed to employ a fungal pretreatment of oxytetracycline (OTC)-rich wastewater, before its disposal in a BPS used for the treatment of two pesticides. The fungal treatment at reactor scale (stirred tank reactor, 3L) with biomass of Trametes versicolor efficiently removed 100 mg L-1 OTC in only 60 h. However, ecotoxicity tests on seed germination with Lactuca sativa revealed that antibiotic elimination did not correlate with a decrease in toxicity. After the pretreatment, treated OTC was discarded in biomixtures used for the elimination of the herbicides ametryn and terbutryn. The co-application of treated or untreated OTC did not inhibit the removal of the herbicides; moreover, in both cases their removal seemed to be slightly enhanced in the presence of OTC or its residues, with respect to antibiotic-free biomixtures. Estimated half-lives ranged from 28.4 to 34.8 d for ametryn, and 34.0-51.0 d for terbutryn. In addition, the biomixture was also able to remove OTC in the presence of the herbicides, with an estimated half-life of 38 d. Remarkably, the toxicity of the wastewater containing OTC or treated OTC was mostly eliminated after its disposal in the biomixture. Overall results suggest that, given the high efficiency of the biomixture, the fungal pretreatment of OTC-containing wastewater is not mandatory before its disposal in the BPS.


Assuntos
Reatores Biológicos/microbiologia , Herbicidas/análise , Oxitetraciclina/análise , Trametes/crescimento & desenvolvimento , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Agricultura , Biodegradação Ambiental , Germinação/efeitos dos fármacos , Meia-Vida , Oxitetraciclina/toxicidade , Águas Residuárias/química , Poluentes Químicos da Água/toxicidade
8.
Int J Med Mushrooms ; 20(10): 971-987, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30806269

RESUMO

In this study, a wide diversity in lignin-modifying enzyme (LME) secretion by 11 Trametes spp. strains isolated from the forests of Georgia was revealed in their submerged cultivation in both synthetic and lignocellulose-based media. Among them, T. multicolor BCC 511 was distinguished by simultaneous production of laccase, manganese peroxidase (MnP), and lignin peroxidase (LiP) in the presence of high carbon and nitrogen concentrations. Mannitol at the concentration of 15 g/L provided an accumulation of 23.7 U/mL laccase and 0.56 U/mL MnP. Significant modulation of LME activity by lignocellulosic substrates, metals, aromatic compounds, and their concentrations was established. Mandarin peels manifold increased the fungus laccase and LiP activities, while the ethanol production residue and banana peels activated manganese-oxidizing and Phenol Red-oxidizing manganese peroxidases, respectively. The addition of 2 mM of copper sulfate to the control medium induced the laccase production 28-fold and did not significantly affect the MnP and LiP activities. Fe2+ at a concentration of 0.1 mM enhanced the fungus volumetric and specific laccase activities almost 8-fold; at a concentration of 0.25-0.5 mM, there was a 2-fold increase in the MnP activity. Mn2+ appeared to be an effective inducer of the Mn-oxidizing MnP, increasing specific activity of the enzyme 14-fold. Supplementation of the copper-containing medium with 1 mM veratryl alcohol or guaiacol favored laccase and MnP production. The high yields of laccase (110 U/mL), MnP (0.62 U/mL), and LiP (0.71 U/mL) obtained in a laboratory fermenter make T. multicolor 511 useful for industrial and environmental applications.


Assuntos
Lignina/metabolismo , Trametes/enzimologia , Reatores Biológicos , Carbono/metabolismo , Meios de Cultura , República da Geórgia , Hidrocarbonetos Aromáticos/metabolismo , Nitrogênio/metabolismo , Trametes/crescimento & desenvolvimento
9.
An Acad Bras Cienc ; 89(4): 2647-2655, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29236849

RESUMO

The impacts of white-rot fungi on altering wood chemistry have been studied mostly in vitro. However, in vivo approaches may enable better assessment of the nature of interactions between saprotrophic fungi and host tree in nature. Hence, decayed and sound wood samples were collected from a naturally infected tree (Carpinus betulus L.). Fruiting bodies of the white rot fungus Trametes versicolor grown on the same tree were identified using rDNA ITS sequencing. Chemical compositions (cellulose and lignin) of both sound and infected wood were studied. FT-IR spectroscopy was used to collect spectra of decayed and un-decayed wood samples. The results of chemical compositions indicated that T. versicolor reduced cellulose and lignin in similar quantities. Fungal activities in decayed wood causes serious decline in pH content. The amount of alcohol-benzene soluble extractives was severely decreased, while a remarkable increase was found in 1% sodium hydroxide soluble and hot water extractive contents in the decayed wood samples, respectively. FT-IR analyses demonstrated that T. versicolor causes simultaneous white rot in the hornbeam tree in vivo which is in line with in vitro experiments.


Assuntos
Trametes/crescimento & desenvolvimento , Árvores/microbiologia , Madeira/microbiologia , Fenômenos Ecológicos e Ambientais , Espectroscopia de Infravermelho com Transformada de Fourier , Árvores/química , Madeira/química
10.
An. acad. bras. ciênc ; 89(4): 2647-2655, Oct.-Dec. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886848

RESUMO

ABSTRACT The impacts of white-rot fungi on altering wood chemistry have been studied mostly in vitro. However, in vivo approaches may enable better assessment of the nature of interactions between saprotrophic fungi and host tree in nature. Hence, decayed and sound wood samples were collected from a naturally infected tree (Carpinus betulus L.). Fruiting bodies of the white rot fungus Trametes versicolor grown on the same tree were identified using rDNA ITS sequencing. Chemical compositions (cellulose and lignin) of both sound and infected wood were studied. FT-IR spectroscopy was used to collect spectra of decayed and un-decayed wood samples. The results of chemical compositions indicated that T. versicolor reduced cellulose and lignin in similar quantities. Fungal activities in decayed wood causes serious decline in pH content. The amount of alcohol-benzene soluble extractives was severely decreased, while a remarkable increase was found in 1% sodium hydroxide soluble and hot water extractive contents in the decayed wood samples, respectively. FT-IR analyses demonstrated that T. versicolor causes simultaneous white rot in the hornbeam tree in vivo which is in line with in vitro experiments.


Assuntos
Árvores/microbiologia , Madeira/microbiologia , Trametes/crescimento & desenvolvimento , Árvores/química , Madeira/química , Espectroscopia de Infravermelho com Transformada de Fourier , Fenômenos Ecológicos e Ambientais
11.
Sci Rep ; 7(1): 5265, 2017 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-28706236

RESUMO

Interspecific fungal antagonism occurred commonly in the interaction zone of different white rot fungi. This competitive interaction could markedly influence the metabolic pathway of intracellular metabolites, which was associated with the fungal morphology change and growth restriction. So far, it remains unknown on intracellular metabolite regulation during fungal competitive interaction. Herein, we performed the metabolomic analysis of the in vivo metabolite changes during competitive interaction between each two of the three white rot fungi Trametes versicolor, Pleurotus ostreatus and Dichomitus squalens and identified differential metabolites in the interaction zone compared to each two isolates. Many metabolites in the carnitine, lipid, ethylene and trehalose metabolic pathways were significantly up-regulated. These metabolic pathways are all involved in defensive response to abiotic and/or biotic stressful condition.


Assuntos
Proteínas Fúngicas/metabolismo , Redes e Vias Metabólicas , Metaboloma , Pleurotus/metabolismo , Polyporaceae/metabolismo , Trametes/metabolismo , Pleurotus/crescimento & desenvolvimento , Polyporaceae/crescimento & desenvolvimento , Trametes/crescimento & desenvolvimento
12.
J Appl Microbiol ; 123(4): 886-895, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28718996

RESUMO

AIMS: The aim of this study was to evaluate the synthesis of ligninolytic enzymes and some diffusible antifungal compounds by white-rot fungi (WRF) using peels or discarded potato as the sole nutrient source. METHODS AND RESULTS: The strain Trametes hirsuta Ru-513 highlighted for its laccase activity (595 ± 33 U l-1 ), which is able to decolourize 87% of an anthraquinone dye using potato peels as the sole nutritional support. A native polyacrylamide gel of laccase proteins showed the presence of two isoenzymes, corresponding to proteins of 56 and 67 kDa, which were detected by SDS-PAGE. The antifungal activity of ethyl acetate extracts was evaluated by the agar diffusion method, where Anthracophyllum discolor Sp4 and Inonotus sp. Sp2 showed the highest inhibition zones of Mucor miehei. The fungal extracts also inhibited Fusarium oxysporum and Botrytis cinerea growth, with inhibition zones of up to 18 mm. The extract with the highest antifungal activity, from A. discolor Sp4 grown in discarded potato medium, was analysed using a gas chromatograph coupled to a mass spectrometer. Among the identified compounds, chlorinated aromatic compounds and veratryl alcohol were the most abundant compounds. CONCLUSIONS: The results revealed the relevance of potato waste valorization for the sustainable production of ligninolytic enzymes and antifungal compounds. SIGNIFICANCE AND IMPACT OF THE STUDY: This study reports the synthesis of ligninolytic enzymes and diffusible antifungal compounds by WRF using potato wastes as the sole nutrient source and suggests a relationship between the enzymatic activity and the synthesis of antifungal compounds. These compounds and the synthesis of halogen compounds by WRF using agro-industrial wastes have been poorly studied before.


Assuntos
Agaricales/metabolismo , Antifúngicos/metabolismo , Proteínas Fúngicas/metabolismo , Lacase/metabolismo , Solanum tuberosum/microbiologia , Resíduos Sólidos/análise , Trametes/enzimologia , Agaricales/química , Agaricales/crescimento & desenvolvimento , Corantes/metabolismo , Meios de Cultura/metabolismo , Eletroforese em Gel de Poliacrilamida , Proteínas Fúngicas/química , Resíduos Industriais/análise , Trametes/química , Trametes/crescimento & desenvolvimento , Trametes/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-28463583

RESUMO

The mycoremediation has been considered as a promising method for decolorizing dye wastewater. To explore new bioresource for mycoremediation, a new white-rot fungus that could decolorize various dyes commonly used in textile industries was isolated, and its ligninolytic enzyme activity and decolorization capacity were characterized. The isolated CBR43 was identified as Trametes versicolor based on the morphological properties of its fruit body and spores, as well as through partial 18S rDNA gene sequences. Isolated CBR43 displayed high activities of laccase and Mn-dependent peroxidase, whereas its lignin peroxidase activity was relatively low. These ligninolytic enzyme activities in potato dextrose broth (PDB) medium were enhanced by the addition of yeast extract (1-10 g L-1). In particular, lignin peroxidase activity was increased more than 5 times in the PDB medium amended with 10 g L-1 of yeast extract. The CBR43 decolorized more than 90% of 200 mg L-1 acid dyes (red 114, blue 62 and black 172) and reactive dyes (red 120, blue 4, orange 16 and black 5) within 6 days in the PDB medium. CBR43 decolorized 67% of 200 mg L-1 acid orange 7 within 9 days. The decolorization efficiencies for disperse dyes (red 1, orange 3 and black 1) were 51-80% within 9 days. The CBR43 could effectively decolorize high concentrations of acid blue 62 and acid black 172 (500-700 mg L-1). The maximum dye decolorization rate was obtained at 28°C, pH 5, and 150 rpm in the PDB medium. T. versicolor CBR43 had high laccase and Mn-dependent peroxidase activities, and could decolorize a wide variety of dyes such as acid, disperse and reactive textile dyes. This fungus had decolorizing activities of azo-type dyes as well as anthraquinone-type dyes. T. versicolor CBR43 is one of promising bioresources for the decolorization of textile wastewater including various dyes.


Assuntos
Compostos Azo/análise , Benzenossulfonatos/análise , Complexos de Coordenação/análise , Naftalenossulfonatos/análise , Trametes/crescimento & desenvolvimento , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Biodegradação Ambiental , Lacase/metabolismo , Peroxidases/metabolismo , Indústria Têxtil , Trametes/enzimologia , Águas Residuárias/química
14.
Appl Biochem Biotechnol ; 183(4): 1401-1413, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28528383

RESUMO

The pretreatment of plant biomass negatively impacts the economics of many bioenergy and bioproduct processes due to the thermochemical requirements for deconstruction of lignocelluluose. An effective strategy to reduce these severity requirements is to pretreat the biomass with white-rot fungi, such as Trametes versicolor, which have the innate ability to deconstruct lignocellulose with a suite of specialized enzymes. In the present study, the effects of 12 weeks of pretreatment with a wild-type strain (52J) and a cellobiose dehydrogenase-deficient strain (m4D) of T. versicolor on hardwood and Miscanthus were explored. Both strains of T. versicolor led to significant decreases of insoluble lignin and significant increases of soluble lignin after acid hydrolysis, which suggests improved lignin extractability. The glucose yields after saccharification using an enzyme cocktail containing chitinase were similar or significantly higher with 52J-treated biomass compared to untreated hardwood and Miscanthus, respectively. The fungal treated biomass, regardless of the strain used, also showed significant increases in energy content and compressive strength of pellets. Overall, the use of T. versicolor as a pretreatment agent for hardwood and Miscanthus could be an environmentally friendly strategy for conversion technologies that require delignification and saccharification, and/or processes that require densification and transport.


Assuntos
Biocombustíveis , Magnoliopsida/química , Trametes/crescimento & desenvolvimento , Madeira/química
15.
Int J Med Mushrooms ; 19(2): 137-144, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28436322

RESUMO

Nomenclature revision and enlarged taxonomical descriptions are still needed for some well-known species whose interpretation is complicated by many nomenclature or taxonomical problems. The polyporoid fungus widely known as Trametes ochracea (= Coriolus zonatus) belongs to such a problematic group. At the same time, recent data show that this species, like its sister species T. versicolor, seems to be a perspective subject for fungal biotechnology and pharmacology. This article is devoted to stabilizing the nomenclature of the species in question via lectotypification and epitypification of Boletus multicolor. It will clarify the name T. multicolor as applied to this species is nomenclaturally correct and useful, free of further problems. An expanded species description and cultural characterization of epitype materials are presented.


Assuntos
Agaricales/classificação , Técnicas de Tipagem Micológica , Trametes/classificação , Agaricales/citologia , Agaricales/crescimento & desenvolvimento , Microscopia , Terminologia como Assunto , Trametes/citologia , Trametes/crescimento & desenvolvimento
16.
Curr Microbiol ; 74(1): 125-131, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27878336

RESUMO

White-rot fungi are the main decomposers of wood cell-wall polymer in forest ecosystems. Little is known, however, about the interactions between white-rot fungi and other coexisting microorganisms in decayed wood. A white-rot fungus, Trametes versicolor strain TN6F, was isolated from a fruit body, and 44 strains of coexisting cultivable bacteria were isolated from its substrate, natural white rot-decayed wood. The effects of these bacteria on fungal growth were examined by an in vitro confrontation growth assay. Among the isolates, nine bacterial strains inhibited the growth of strain TN6F, while 35 strains did not affect the growth of TN6F. However, when co-cultured with strain TN6F on wood powder, many bacterial strains promoted the weight loss of the substrate. A subsequent chemical composition analysis showed that co-culturing accelerated delignification. Higher laccase activity was detected when strain TN6F was co-cultured on wood powder medium with bacterial strains TN6W-26 or TN6W-27. These results indicate that some bacterial strains might promote wood degradation.


Assuntos
Bactérias/metabolismo , Trametes/metabolismo , Madeira/metabolismo , Madeira/microbiologia , Bactérias/crescimento & desenvolvimento , Técnicas de Cocultura , Trametes/crescimento & desenvolvimento
17.
Appl Biochem Biotechnol ; 181(3): 948-960, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27696141

RESUMO

Corn silage is used as high-energy forage for dairy cows and more recently for biogas production in a process of anaerobic co-digestion with cow manure. In this work, fresh corn silage after the harvest was used as a substrate in solid-state fermentations with T. versicolor with the aim of phenolic acid recovery and enzyme (laccase and manganese peroxidase) production. During 20 days of fermentation, 10.4-, 3.4-, 3.0-, and 1.8-fold increments in extraction yield of syringic acid, vanillic acid, p-hydroxybenzoic acid, and caffeic acid, respectively, were reached when compared to biologically untreated corn silage. Maximal laccase activity was gained on the 4th day of fermentation (V.A. = 180.2 U/dm3), and manganese peroxidase activity was obtained after the 3rd day of fermentation (V.A. = 30.1 U/dm3). The addition of copper(II) sulfate as inducer during solid state fermentation resulted in 8.5- and 7-fold enhancement of laccase and manganese peroxidase activities, respectively. Furthermore, the influence of pH and temperature on enzyme activities was investigated. Maximal activity of laccase was obtained at T = 50 °C and pH = 3.0, while manganese peroxidase is active at temperature range T = 45-70 °C with the maximal activity at pH = 4.5.


Assuntos
Proteínas Fúngicas/biossíntese , Hidroxibenzoatos/metabolismo , Lacase/biossíntese , Peroxidases/biossíntese , Silagem/microbiologia , Trametes/crescimento & desenvolvimento , Zea mays , Animais , Bovinos
18.
J Gen Appl Microbiol ; 62(6): 303-312, 2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-27885193

RESUMO

The biodegradation of three polycyclic aromatic hydrocarbons (PAHs), phenanthrene, fluorene, and pyrene, by a newly isolated thermotolerant white rot fungal strain RYNF13 from Thailand, was investigated. The strain RYNF13 was identified as Trametes polyzona, based on an analysis of its internal transcribed spacer sequence. The strain RYNF13 was superior to most white rot fungi. The fungus showed excellent removal of PAHs at a high concentration of 100 mg·L-1. Complete degradation of phenanthrene in a mineral salt glucose medium culture was observed within 18 days of incubation at 30°C, whereas 90% of fluorene and 52% of pyrene were degraded under the same conditions. At a high temperature of 42°C, the strain RYNF13 was still able to grow, and degraded approximately 68% of phenanthrene, whereas 48% of fluorene and 30% of pyrene were degraded within 32 days. Thus, the strain RYNF13 is a potential fungus for PAH bioremediation, especially in a tropical environment where the temperature can be higher than 40°C. The strain RYNF13 secreted three different ligninolytic enzymes, manganese peroxidase, laccase, and lignin peroxidase, during PAH biodegradation at 30°C. When the incubation temperature was increased from 30°C to 37°C and 42°C, only two ligninolytic enzymes, manganese peroxidase and laccase, were detectable during the biodegradation. Manganese peroxidase was the major enzyme produced by the fungus. In the culture containing phenanthrene, manganese peroxidase showed the highest enzymatic activity at 179 U·mL-1. T. polyzona RYNF13 was determined as a potential thermotolerant white rot fungus, and suitable for application in the treatment of PAH-containing contaminants.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Trametes/metabolismo , Biodegradação Ambiental , Carcinógenos/metabolismo , Carcinógenos/farmacologia , Meios de Cultura/química , DNA Espaçador Ribossômico , Fluorenos/metabolismo , Fluorenos/farmacologia , Glucose/farmacologia , Lacase/biossíntese , Peroxidases/biossíntese , Fenantrenos/metabolismo , Fenantrenos/farmacologia , Hidrocarbonetos Policíclicos Aromáticos/farmacologia , Pirenos/metabolismo , Pirenos/farmacologia , Temperatura , Tailândia , Trametes/genética , Trametes/crescimento & desenvolvimento , Trametes/isolamento & purificação
19.
BMC Microbiol ; 16(1): 106, 2016 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-27296712

RESUMO

BACKGROUND: Fungi are organisms with the highest natural capacity to degrade lignocellulose substrates, which is enabled by complex systems of extracellular enzymes, whose expression and secretion depend on the characteristics of substrates and the environment. RESULTS: This study reports a secretome analysis for white-rot basidiomycete Trametes hirsuta cultivated on a synthetic media and a lignocellulose substrate. We demonstrate that T. hirsuta st. 072 produces multiple extracellular ligninolytic, cellulolytic, hemicellulolytic, peroxide generating, and proteolytic enzymes, as well as cerato-platanins. In contrast to other white rot species described earlier, which mostly secreted glucanases and mannosidases in response to the presence of the lignocellulose substrate, T. hirsuta expressed a spectrum of extracellular cellulolytic enzymes containing predominantly cellobiases and xylanases. As proteomic analysis could not detect lignin peroxidase (LiP) among the secreted lignin degrading enzymes, we attributed the observed extracellular LiP - like activity to the expressed versatile peroxidase (VP). An accessory enzyme, glyoxal oxidase, was found among the proteins secreted in the media during submerged cultivation of T. hirsuta both in the presence and in the absence of copper. However, aryl-alcohol oxidase (AAO) was not identified, despite the presence of AAO enzymatic activity secreted by the fungus. The spectra of the expressed enzymes dramatically changed depending on the growth conditions. Transfer from submerged cultivation to surface cultivation with the lignocellulose substrate switched off expression of exo-ß-1,3-glucanase and α-amylase and turned on secretion of endo-ß-1,3-glucanase and a range of glycosidases. In addition, an aspartic peptidase started being expressed instead of family S53 protease. For the first time, we report production of cerato-platanin proteins by Trametes species. The secretion of cerato-platanins was observed only in response to contact with lignocellulose, thus indicating a specific role of these proteins in degradation of the lignocellulose substrates. CONCLUSIONS: Our results suggest a sequential mechanism of natural substrate degradation by T. hirsuta, in which the fungus produces different sets of enzymes to digest all main components of the substrate during cultivation.


Assuntos
Cobre/farmacologia , Proteínas Fúngicas/metabolismo , Lignina/metabolismo , Trametes/efeitos dos fármacos , Trametes/metabolismo , Oxirredutases do Álcool/metabolismo , Cátions/farmacologia , Celulose/metabolismo , Cobre/química , Sulfato de Cobre/farmacologia , Ativação Enzimática , Glicosídeo Hidrolases , Oxirredutases/metabolismo , Peroxidases/metabolismo , Proteômica , Trametes/enzimologia , Trametes/crescimento & desenvolvimento
20.
Chemosphere ; 152: 301-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26991378

RESUMO

The emergence and spread of antibiotic resistance represents one of the most important public health concerns and has been linked to the widespread use of antibiotics in veterinary and human medicine. The overall elimination of antibiotics in conventional wastewater treatment plants is quite low; therefore, residual amounts of these compounds are continuously discharged to receiving surface waters, which may promote the emergence of antibiotic resistance. In this study, the ability of a fungal treatment as an alternative wastewater treatment for the elimination of forty-seven antibiotics belonging to seven different groups (ß-lactams, fluoroquinolones, macrolides, metronidazoles, sulfonamides, tetracyclines, and trimethoprim) was evaluated. 77% of antibiotics were removed after the fungal treatment, which is higher than removal obtained in conventional treatment plants. Moreover, the effect of fungal treatment on the removal of some antibiotic resistance genes (ARGs) was evaluated. The fungal treatment was also efficient in removing ARGs, such as ermB (resistance to macrolides), tetW (resistance to tetracyclines), blaTEM (resistance to ß-lactams), sulI (resistance to sulfonamides) and qnrS (reduced susceptibility to fluoroquinolones). However, it was not possible to establish a clear link between concentrations of antibiotics and corresponding ARGs in wastewater, which leads to the conclusion that there are other factors that should be taken into consideration besides the antibiotic concentrations that reach aquatic ecosystems in order to explain the emergence and spread of antibiotic resistance.


Assuntos
Antibacterianos/análise , Resistência Microbiana a Medicamentos/genética , Trametes/crescimento & desenvolvimento , Águas Residuárias , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Animais , Reatores Biológicos/microbiologia , Genes Bacterianos/efeitos dos fármacos , Hospitais Veterinários , Humanos , Espanha , Águas Residuárias/química , Águas Residuárias/microbiologia
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