RESUMO
In dual culture confrontation assays, basidiomycete Irpex lacteus efficiently antagonized Fusarium spp., Colletotrichum spp., and Phytophthora spp. phytopathogenic strains, with growth inhibition percentages between 16.7-46.3%. Antibiosis assays evaluating the inhibitory effect of soluble extracellular metabolites indicated I. lacteus strain inhibited phytopathogens growth between 32.0-86.7%. Metabolites in the extracellular broth filtrate, identified by UPLC-QTOF mass spectrometer, included nine terpenes, two aldehydes, and derivatives of a polyketide, a quinazoline, and a xanthone, several of which had antifungal activity. I. lacteus strain and its extracellular metabolites might be valuable tools for phytopathogenic fungi and oomycete biocontrol of agricultural relevance.
Assuntos
Antifúngicos/farmacologia , Fusarium/efeitos dos fármacos , Oomicetos/efeitos dos fármacos , Phytophthora/efeitos dos fármacos , Doenças das Plantas/microbiologia , Polyporales/química , Aldeídos/química , Aldeídos/metabolismo , Aldeídos/farmacologia , Antifúngicos/química , Antifúngicos/metabolismo , Fusarium/crescimento & desenvolvimento , Espectrometria de Massas , Oomicetos/crescimento & desenvolvimento , Phytophthora/crescimento & desenvolvimento , Polyporales/metabolismo , Quinazolinas/química , Quinazolinas/metabolismo , Quinazolinas/farmacologia , Terpenos/química , Terpenos/metabolismo , Terpenos/farmacologiaRESUMO
Ceriporiopsis subvermispora is a white-rot fungus with a high specificity towards lignin mineralization when colonizing dead wood or lignocellulosic compounds. Its lignocellulose degrading system is formed by cellulose hydrolytic enzymes, manganese peroxidases, and laccases that catalyze the efficient depolymerization and mineralization of lignocellulose. To determine if this metabolic specialization has modified codon usage of the lignocellulolytic system, improving its adaptation to the fungal translational machine, we analyzed the adaptation to host codon usage (CAI), tRNA pool (tAI, and AAtAI), codon pair bias (CPB), and the number of effective codons (Nc). These indexes were correlated with gene expression of C. subvermispora, in the presence of glucose and Aspen wood. General gene expression was not correlated with the index values. However, in media containing Aspen wood, the induction of expression of lignocellulose-degrading genes, showed significantly (p < 0.001) higher values of CAI, AAtAI, CPB, tAI, and lower values of Nc than non-induced genes. Cellulose-binding proteins and manganese peroxidases presented the highest adaptation values. We also identified an expansion of genes encoding glycine and glutamic acid tRNAs. Our results suggest that the metabolic specialization to use wood as the sole carbon source has introduced a bias in the codon usage of genes involved in lignocellulose degradation. This bias reduces codon diversity and increases codon usage adaptation to the tRNA pool available in C. subvermispora. To our knowledge, this is the first study showing that codon usage is modified to improve the translation efficiency of a group of genes involved in a particular metabolic process.
Assuntos
Uso do Códon , Lacase/metabolismo , Lignina/metabolismo , Peroxidases/metabolismo , Polyporales/metabolismo , RNA de Transferência/genética , Catálise , Hidrólise , Lacase/genética , Peroxidases/genética , Filogenia , Polyporales/genética , Polyporales/crescimento & desenvolvimentoRESUMO
Trichomonas vaginalis is the causative agent of trichomoniasis, the most common nonviral STD worldwide. This infection can lead to severe health conditions, especially when women are affected. Metronidazole and tinidazole are the only choices of treatment. In this sense, natural bioactive compounds against T. vaginalis are an interesting approach in the search for more efficient therapies. Herein, amaurocine, a 12 kDa protein, produced by the mushroom Amauroderma camerarium was purified and tested against T. vaginalis, including two fresh clinical isolates. Amaurocine presented MIC values at 2.6 µM against the ATCC isolate 30236, and 5.2 µM against the fresh clinical isolates, TV-LACH1 and TV-LACM2. Furthermore, besides increasing human neutrophils nitric oxide release, amaurocine presented a low toxicity toward those cells, suggesting it exerts a proinflammatory character.
Assuntos
Antiprotozoários/farmacologia , Proteínas Fúngicas/farmacologia , Polyporales/metabolismo , Trichomonas vaginalis/efeitos dos fármacos , Antiprotozoários/metabolismo , Antiprotozoários/toxicidade , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/química , Proteínas Fúngicas/toxicidade , Humanos , Testes de Sensibilidade Microbiana , Micélio/química , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Óxido Nítrico/metabolismo , Polyporales/químicaRESUMO
A general procedure to study the biodegradation of endosulfan under laboratory conditions by white rot fungi isolated from native sources growing in YNB (yeast nitrogen base) media with 1% of glucose is presented. The evaluation of endosulfan biodegradation as well as endosulfan sulfate, endosulfan ether and endosulfan alcohol production throughout the whole bioremedation process was performed using an original and straightforward validated analytical procedure with recoveries between 78 and 112% at all concentration levels studied except for endosulfan sulfate at 50 mg L(-1) that yielded 128% and RSDs<20%. Under the developed conditions, the basidiomycete Bjerkandera adusta was able to degrade 83% of (alpha+beta) endosulfan after 27 days, 6 mg kg(-1) of endosulfan diol were determined; endosulfan ether and endosulfan sulfate were produced below 1 mg kg(-1) (LOQ, limit of quantitation).
Assuntos
Cromatografia Gasosa/métodos , Endossulfano/análogos & derivados , Endossulfano/metabolismo , Polyporales/metabolismo , Biodegradação Ambiental , Fracionamento Químico , Endossulfano/análise , Endossulfano/química , Praguicidas/análise , Praguicidas/química , Praguicidas/metabolismo , Reprodutibilidade dos TestesRESUMO
An α-galactosidase was isolated from a culture filtrate of Lenzites elegans (Spreng.) ex Pat. MB445947 grown on citric pectin as carbon source. It was purified to electrophoretic homogeneity by ammonium sulfate precipitation, gel filtration chromatography and anion-exchange chromatography. The relative molecular mass of the native purified enzyme was 158 kDa determined by gel filtration and it is a homodimer (Mr subunits = 61 kDa). The optimal temperature for enzyme activity was in the range 60-80 °C. This α-galactosidase showed a high thermostability, retaining 94 % of its activity after preincubation at 60 °C for 2 h. The optimal pH for the enzyme was 4.5 and it was stable from pH 3 to 7.5 when the preincubation took place at 60 °C for 2 h. It was active against several α-galactosides such as p-nitrophenyl-α-D-galactopyranoside, α-D-melibiose, raffinose and stachyose. The α-galactosidase is a glycoprotein with 26 % of structural sugars. Galactose was a non-competitive inhibitor with a Ki = 22 mM versus p-nitrophenyl-α-D-galactoside and 12 mM versus α-D-melibiose as substrates. Glucose was a simple competitive inhibitor with a Ki = 10 mM. Cations such as Hg(2+) and p-chloromercuribenzoate were also inhibitors of this activity, suggesting the presence of -SH groups in the active site of the enzyme. On the basis of the sequence of the N-terminus (SPDTIVLDGTNFALN) the studied α-galactosidase would be a member of glycosyl hydrolase family 36 (GH 36). Given the high optimum temperature and heat stability of L. elegans α-galactosidase, this fungus may become a useful source of α-galactosidase production for multiple applications.
Assuntos
Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Polyporales/enzimologia , alfa-Galactosidase/química , alfa-Galactosidase/isolamento & purificação , Sequência de Aminoácidos , Estabilidade Enzimática , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Temperatura Alta , Concentração de Íons de Hidrogênio , Cinética , Dados de Sequência Molecular , Peso Molecular , Polyporales/química , Polyporales/genética , Polyporales/metabolismo , Alinhamento de Sequência , Especificidade por Substrato , alfa-Galactosidase/genética , alfa-Galactosidase/metabolismoRESUMO
Jasmonic acid is a native plant growth regulator produced by algae, microorganisms and higher plants. This regulator is involved in the activation of defence mechanisms against pathogens and wounding in plants. Studies concerning the effects of carbon: nitrogen ratio (C/Nr: 17, 35 and 70), type of inoculum (spores or mycelium) and the yeast extract addition in the media on jasmonic acid production by Botryodiplodia theobromae were evaluated. Jasmonic acid production was stimulated at the carbon: nitrogen ratio of 17. Jasmonic acid productivity was higher in the media inoculated with mycelium and in the media with yeast extract 1.7 and 1.3 times, respectively.
Assuntos
Carbono/administração & dosagem , Carbono/metabolismo , Misturas Complexas/administração & dosagem , Misturas Complexas/metabolismo , Ciclopentanos/metabolismo , Nitrogênio/administração & dosagem , Nitrogênio/metabolismo , Oxilipinas/metabolismo , Polyporales/metabolismo , Leveduras , Meios de CulturaRESUMO
Decolorization of 100 microM malachite green (MG) by Coriolus versicolor f. antarcticus using a two-phase bioreactor, was investigated. In the first phase the decolorization ability of this fungus, growing under conditions of solid-state fermentation (SSF), was proved; in the second phase the capacity of the enzymes present in extracts from the solid residues was exploited. During the first phase using the same culture in the bioreactor, five consecutive charges were made, each with 75 ml of 100 microM MG solution, at 28 degrees C. Each cycle ended when MG solution reached a decolorization of 50%, at this time the bioreactor was discharged to a stainless steel coil at 50 degrees C, initiating the second phase of decolorization. Time required in order to reach 50% decolorization during the first phase varied between 25 and 65 min, with an average retention time of 48 min. The second stage had a retention time of 120 min. Residual MG after this phase varied from 0% to 6.3%. The role of laccase and Mn-peroxidase in MG decolorization is discussed. Toxicity of MG solutions before and after decolorization treatments was assayed using Lumbriculus variegatus as test organism.
Assuntos
Reatores Biológicos/microbiologia , Corantes/metabolismo , Polyporales/metabolismo , Cor , Corantes/química , Fermentação , Lacase/metabolismo , Polyporales/enzimologia , Polyporales/crescimento & desenvolvimentoRESUMO
AIMS: The main objective of this study was to evaluate the behaviour of the brown-rot fungus Wolfiporia cocos under differential iron availability. METHODS AND RESULTS: W. cocos was grown under three differential iron conditions. Growth, catecholate and hydroxamate production, and mycelial and extracellular Fe3+-reducing activities were determined. Iron starvation slowed fungal growth and accelerated pH decline. Some mycelial proteins of low molecular weight were repressed under iron restriction, whereas others of high molecular weight showed positive iron regulation. Mycelial ferrireductase activity decreased as culture aged, while Fe3+-reducing activity of low molecular reductants constantly increased. Hydroxamates production suffered only limited iron repression, whereas catecholates production showed to be more iron repressible. CONCLUSIONS: W. cocos seems to possess more than one type of iron acquisition mechanism; one involving secretion of organic acids and ferrireductases and/or extracellular reductants, and another relying on secretion of catecholates and hydroxamates chelators. SIGNIFICANCE AND IMPACT OF THE STUDY: This paper is the first to report the kinetic study of brown-rot fungus grown under differential iron availability, and the information provided here contributes to address more traditional problems in protecting wood from brown decay, and also makes a contribution in the general area of the physiology of brown-rot fungi.
Assuntos
Proteínas Fúngicas/metabolismo , Microbiologia Industrial , Ferro/metabolismo , Doenças das Plantas/microbiologia , Polyporales/metabolismo , Madeira , Eletroforese em Gel de Poliacrilamida , FMN Redutase/metabolismo , Ferro/farmacologia , Quelantes de Ferro/metabolismo , Micologia , Polyporales/crescimento & desenvolvimento , Coloração pela PrataRESUMO
An efficient sequential, biological and photocatalytic treatment to reduce the pollutant levels in wastewater due to the bleaching process during paper production is reported. For a biological pre-treatment, 800 ml of non-sterilized effluent was inoculated with Trametes versicolor immobilized in polyurethane foam, with 25 g l(-1) glucose, 6.75 mM CuSO(4), and 0.22 mM MnSO(4) added, and cultured at 25 degrees C with an air flow of 800 ml min(-1) for 8d. The fungus did not inhibit growth of the heterotropic populations of the effluent. After 4d of culture, the chemical oxygen demand (COD) reduction and colour removal (CR) were 82% and 80%, respectively, with laccase (LAC) and manganese peroxidase (MnP) activities of 345 U l(-1) and 78 U l(-1), respectively. The COD reduction and CR correlated positively (p<0.0001) with LAC and MnP activities. Chlorophenol removal was 99% of pentachlorophenol, 99% of 2,3,4,6-tetrachlorophenol (2,3,4,6-TCP), 98% of 3,4-dichlorophenol (3,4-DCP) and 77% of 4-chlorophenol (4-CP), while 2,4,5-trichlorophenol (2,4,5-TCP) increased to 0.2 mg l(-1). The pre-treated effluent was then exposed to a photocatalytic treatment. The treatment with photolysis resulted in 9% CR and 46% COD reduction, 42% CR and 60% COD reduction by photocatalysis, and 62% CR and 85% COD reduction by heterogeneous photocatalysis with the system TiO(2)/Ru(x)Se(y) (Fig. 4). With this treatment the bacterial and fungal populations also decreased by 5 logarithmic units with respect to the biological treatment alone (Fig. 5). The total sequential treatment resulted in a 92% CR (from 5800 UC), 97% COD reduction (from 59 g l(-1)) and 99% chlorophenol removal at 96 h and 20 min.
Assuntos
Biodegradação Ambiental , Clorofenóis/química , Clorofenóis/efeitos da radiação , Resíduos Industriais , Polyporales/metabolismo , Rutênio/química , Titânio/química , Raios Ultravioleta , Poluentes Químicos da Água/química , Poluentes Químicos da Água/efeitos da radiação , Purificação da Água/métodos , Catálise , Clorofenóis/metabolismo , Nanopartículas Metálicas , Papel , Eliminação de Resíduos Líquidos/métodosRESUMO
We previously identified and characterized three mnp genes coding for manganese peroxidase (MnP) in the white rot fungus Ceriporiopsis subvermispora. In this work, we assessed transcript levels of mnp genes in liquid cultures of this fungus grown under various conditions. In the absence of Mn(2+), mnp1 and mnp2 mRNA were detected by Northern hybridization, irrespective of the lack of extracellular MnP activity. Addition of Mn(2+) to the cultures led to a marked increase in both transcripts, the highest titers being observed at 10 micro M Mn(2+). mnp1 mRNA was not detected at Mn(2+ )concentrations above 80 micro M, whereas mnp2 mRNA was still observed at 320 micro M Mn(2+). Differential regulation of these genes was confirmed by the addition of Cu(2+), Zn(2+), Ag(+) and Cd(2+). These metal ions dramatically elevated both transcripts and also allowed the detection of the mnp3 transcript. In most cases, the increase in mRNA levels was partially abolished by the simultaneous presence of Mn(2+), although the latter was strictly required to detect extracellular MnP activity. However, the lignin-related compound syringic acid specifically increased the mnp1 transcript, although only in the absence of Mn(2+). These results indicate that there is no clear correlation between mnp mRNA levels and MnP activity. In addition, they strongly suggest that Mn(2+) plays a post-transcriptional role which is essential for the presence of active MnP in the extracellular fluid.
Assuntos
Ácido Gálico/análogos & derivados , Regulação Fúngica da Expressão Gênica , Peroxidases/genética , Polyporales/genética , Ácido Gálico/farmacologia , Metais/farmacologia , Peroxidases/metabolismo , Polyporales/metabolismo , Regiões Promotoras Genéticas , Processamento Pós-Transcricional do RNA/genética , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/biossíntese , Transcrição GênicaRESUMO
The ability of the ligninolytic fungus Trametes trogii to degrade in vitro different xenobiotics (PCBs, PAHs and dyes) was evaluated. Either 200 ppm of a PCB mixture (Aroclor 1150) or 160 ppm of an industrial PAH mixture (10% V/V of PAHs, principal components hexaethylbenzene, naphthalene, 1-methyl naphthalene, acenaphthylene, anthracene, fluorene and phenanthrene), were added to trophophasic and idiophasic cultures growing in a nitrogen limited mineral medium (glucose/asparagine) and in a complex medium (malt extract/glucose). Gas-liquid chromatography proved that within 7 to 12 d more than 90% of the organopollutants added were removed. The decrease in absorbance at 620 nm demonstrated that cultures of this fungus were able to transform 80% of the dye Anthraquinone-blue (added at a concentration of 50 ppm) in 1.5 h. Enzyme estimations indicated high activity of laccase (up to 0.55 U/mL), as well as lower production of manganese-peroxidase. Laccase activity, detected in all the conditions assayed, could be implicated in the degradation of these organopollutants. Considering the results obtained, T. trogii seems promising for detoxification.
Assuntos
Biodegradação Ambiental , Polyporales/metabolismo , Poluentes do Solo/metabolismo , Arocloros/metabolismo , Indústria Química , Corantes/metabolismo , Proteínas Fúngicas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Aromáticos/metabolismo , Resíduos Industriais , Lacase , Oxirredutases/metabolismo , Bifenilos Policlorados/metabolismo , Xenobióticos/metabolismoRESUMO
The ability of the ligninolytic fungus Trametes trogii to degrade in vitro different xenobiotics (PCBs, PAHs and dyes) was evaluated. Either 200 ppm of a PCB mixture (Aroclor 1150) or 160 ppm of an industrial PAH mixture (10 V/V of PAHs, principal components hexaethylbenzene, naphthalene, 1-methyl naphthalene, acenaphthylene, anthracene, fluorene and phenanthrene), were added to trophophasic and idiophasic cultures growing in a nitrogen limited mineral medium (glucose/asparagine) and in a complex medium (malt extract/glucose). Gas-liquid chromatography proved that within 7 to 12 d more than 90 of the organopollutants added were removed. The decrease in absorbance at 620 nm demonstrated that cultures of this fungus were able to transform 80 of the dye Anthraquinone-blue (added at a concentration of 50 ppm) in 1.5 h. Enzyme estimations indicated high activity of laccase (up to 0.55 U/mL), as well as lower production of manganese-peroxidase. Laccase activity, detected in all the conditions assayed, could be implicated in the degradation of these organopollutants. Considering the results obtained, T. trogii seems promising for detoxification.(AU)
Assuntos
Estudo Comparativo , RESEARCH SUPPORT, NON-U.S. GOVT , Polyporales/metabolismo , Poluentes do Solo/metabolismo , Arocloros/metabolismo , Indústria Química , Corantes/metabolismo , Proteínas Fúngicas/metabolismo , Hidrocarbonetos Aromáticos/metabolismo , Resíduos Industriais , Cromatografia Gasosa-Espectrometria de Massas , Oxirredutases/metabolismo , Bifenilos Policlorados/metabolismo , Xenobióticos/metabolismoRESUMO
The ligninolytic system from the fungi Trametes villosa and Panus crinitus can efficiently degrade all fractions of different molecular mass contained in E1-bleaching effluent, but with different degradation rates. The lower-molecular-mass (MM) materials were better characterized when the elution in the size-exclusion high-performance liquid chromatography were monitored at 210 than at 280 nm, which indicates that these compounds may be ring cleavage byproducts from depolymerized chlorolignin. The biodegradation of E1 effluent by both fungi was a multistage process, involving an initial chemical modification of the higher-MM compounds and concomitant oxidation of the lower-MM materials. A subsequent depolymerization of chemically modified polymeric lignin-like compounds also took place. Each stage may require one or several different enzymes. The results suggested that laccase was involved in the initial stage.
Assuntos
Lignina/análogos & derivados , Lignina/metabolismo , Papel , Biodegradação Ambiental , Biotecnologia , Cromatografia Líquida de Alta Pressão , Lacase , Lignina/química , Peso Molecular , Oxirredutases/metabolismo , Peroxidases/metabolismo , Polyporales/metabolismo , Especificidade da Espécie , Eliminação de Resíduos LíquidosRESUMO
The kinetics of Mn3+-oxalate formation and decay were investigated in reactions catalyzed by manganese peroxidase (MnP) from the basiomycete Ceriporiopsis subvermispora in the absence of externally added hydrogen peroxide. A characteristic lag observed in the formation of this complex was shortened by glyoxylate or catalytic amounts of Mn3+ or hydrogen peroxide. MnP titers had a minor effect on this lag and did not influence the decay rate of the complex. In contrast, Mn2+ and oxalate drastically affected maximal concentrations of the Mn3+-oxalate complex formed, the decay of which was accelerated at high Mn2+ levels. The highest concentration of complex was obtained at pH 4.0, whereas an inverse relationship was found between the pH of the reaction and the decay rate of the complex with MnP present. In the absence of MnP, the best fit for the decay kinetics of the complex gave an order of 3/2 at concentrations in the range of 30-100 microM, with a kobs = 0.012 min-1 M-0.5 at pH 4.0. The rate constant increases at lower pH values and decreases at high oxalate concentrations. The physiological relevance of these findings is discussed.
Assuntos
Manganês/metabolismo , Oxalatos/metabolismo , Peroxidases/metabolismo , Polyporales/metabolismo , Catalase/metabolismo , Cátions/metabolismo , Ativação Enzimática/efeitos dos fármacos , Glioxilatos/farmacologia , Meia-Vida , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Concentração de Íons de Hidrogênio , Cinética , Compostos de Manganês/farmacologia , Oxidantes/metabolismo , Oxirredução , Peroxidases/antagonistas & inibidores , Peroxidases/isolamento & purificação , Polyporales/enzimologia , Sulfatos/farmacologia , Superóxido Dismutase/metabolismoRESUMO
A cDNA (MnP13-1) and the Cs-mnp1 gene encoding for an isoenzyme of manganese peroxidase (MnP) from C. subvermispora were isolated separately and sequenced. The cDNA, identified in a library constructed in the vector Lambda ZIPLOX, contains 1285 nucleotides, excluding the poly(A) tail, and has a 63% G+C content. The deduced protein sequence shows a high degree of identity with MnPs from other fungi. The mature protein contains 364 amino acids, which are preceded by a 24-amino-acid leader sequence. Consistent with the peroxidase mechanism of MnP, the proximal histidine, the distal histidine and the distal arginine are conserved, although the aromatic binding site (L/V/I-P-X-P) is less hydrophilic than those of other peroxidases. A gene coding for the same protein (Cs-mnp1) was isolated from a genomic library constructed in Lambda GEM-11 vector using the cDNA MnP13-1 as a probe. A subcloned SacI fragment of 2.5kb contained the complete sequence of the Cs-mnp1 gene, including 162bp and 770bp of the upstream and downstream regions, respectively. The Cs-mnp1 gene possesses seven short intervening sequences. The intron splice junction sequences as well as the putative internal lariat formation sites adhere to the GT-AG and CTRAY rules, respectively. To examine the structure of the regulatory region of the Cs-mnp1 gene further, a fragment of 1.9kb was amplified using inverse PCR. A putative TATAA element was identified 5' of the translational start codon. Also, an inverted CCAAT element, SP-1 and AP-2 sites and several putative heat-shock and metal response elements were identified.