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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Isolation, purification and characterization of a novel glucose oxidase from Penicillium canescens Tt42

Simpson, Clinton January 2006 (has links)
A novel glucose oxidase from Penicillium canescens (Tt42) was isolated, purified and characterised. The P. canescens Tt42 was cultivated using an optimised growth medium from literature, and maximum glucose oxidase activities of 11.5 U/ml and 6.9 U/ml for the intra- and extracellular fractions were obtained. Maximum glucose oxidase production was achieved after 72 hours at 28°C which coincided with glucose depletion. A total of 1104 U (from 60ml) of glucose oxidase was produced with a biomass specific glucose oxidase activity of 1.08 Umg[superscript -1] Four methods of cell disruption were evaluated for release of intracellular glucose oxidase from P. canescens Tt42 cells. These methods were; sonication, French press, Freeze-Thaw and a high pressure cell disrupter (Z-Plus Series) from Constant systems. All the methods were successful in releasing the intracellular glucose oxidase from P. canescens Tt42. The use of the Constant Systems high pressure cell disrupter was preferred, since it was the simplest and most rapid method. Ammonium sulphate precipitation was shown to be effective as an initial purification step for extracellular glucose oxidase from P. canescens Tt42. Comparison of the intra- and extracellular glucose oxidase fractions using isoelectric focusing showed 2 isoenzymes in both fractions. The pI values of the isoenzymes were determined to be 4.30 and 4.67, with the former being dominant. Since both the intra- and extracellular fractions contained the same isoenzymes of glucose oxidase, further purification studies were performed using the extracellular fraction. The glucose oxidase from P. canescens Tt42 was purified using 3 main techniques: ammonium sulphate precipitation (60% - 70% cut), anion exchange chromatography (Super Q 650M) and size exclusion chromatography (Sephadex S200HR). The glucose oxidase was determined to be ±80% pure by size exclusion chromatography. The final purified glucose oxidase was lyophilised, and an overall purification yield of 10.3% was achieved with an 8.6-fold purification. The purified glucose oxidase was confirmed to be catalase free. Glucose oxidase from P. canescens Tt42 was determined to be a dimeric protein (M[subscript r] ±148kDa) likely consisting of 2 equal subunits (M[subscript r] ± 70kDa). The temperature optimum range was shown to be 25-30°C. The optimum pH for the oxidation of β-D-glucose was pH 7. The enzyme was shown to be stable at 25°C for 10 hours, with a half life of approximately 30 minutes at 37°C. The lyophilised enzyme was stable at -20°C for 6 months. The properties of glucose oxidase from Tt42 were comparable to alternative glucose oxidase enzymes from Aspergillus and other Penicillium species. Glucose oxidase from P. canescens Tt42 was shown to have distinct kinetic characteristics. The V[subscript max] and K[subscript m] were shown to be 651 Umg[superscript -1] and 18.4 mM towards β-D-glucose. The catalytic kcat and specificity k[subscript cat]/K[subscript m] constants for glucose oxidase from P. canescens Tt42 were shown to be 791 s[superscript -1] and 40 s[superscript -1]mM[superscript -1] each respectively. The specificity constant (k[subscript cat]/K[subscript m]) of glucose oxidase from P. canescens Tt42 was determined to be 1.3-fold higher than that that of A. niger (Sigma Type VII) and 8.7-fold lower than that of P. amagasakiense (ATCC 28686) from literature.
52

Studies on metabolism in Penicillium charlesii : some relationships between dicarboxylic acid metabolism and production of galactocarolose /

Jordan, John Maxwell January 1963 (has links)
No description available.
53

Biodiversity in the genus Penicillium from coastal fynbos soil /

Visagie, Cobus M. January 2008 (has links)
Thesis (MSc)--University of Stellenbosch, 2008. / Bibliography. Also available via the Internet.
54

Characterization of lipoxygenases and associated enzymes from selected microorganisms

Perraud, Xavier. January 2000 (has links)
Biomasses of Penicillium camemberti, Penicillium roqueforti and Geotrichum candidum strains were grown and harvested after a culture incubation period that corresponded to the maximal dry weight of mycelium as well as to lipoxygenase (LOX) activity. The crude enzymatic extracts were recovered from the homogenized mycelium cells and the partially purified LOX extracts were obtained by ammonium sulfate precipitation. Using linoleic acid as substrate, the partially purified LOX extracts from P. camemberti, P. roqueforti and G. candidum exhibited a major activity, at pH 6.50, 5.50 and 3.75, respectively, and a minor one at pH 8.00. The partially purified LOX extracts exhibited an overall preferential specificity towards free fatty acids, including linoleic, linolenic and arachidonic acids, than that for fatty acid acylglycerols, including mono-, di- and tri-linolein. The Km and Vmax values for partially purified LOXs were investigated. Normal phase high-performance liquid chromatography (NP-HPLC) and gas-liquid chromatography/mass spectrometry (GC/MS) analyses showed that the LOX activity of the partially purified LOX extracts converted mainly linoleic acid into the corresponding 9- and 13-hydroperoxides (HPODs); however, the production of a relatively important proportion of 10-HPOD, ranging from 4 to 9% of the total HPODs, was also demonstrated with the partially purified LOX extracts from Penicillium sp. The chiral phase HPLC analysis demonstrated the production, by the partially purified LOX extracts from Penicillium sp., of both (R)- and (S)-enantiomers of HPODs, with a slightly higher proportion of the (S)-enantiomers. The crude enzymatic extracts from Penicillium sp. were incubated, at pH 6.50, with individual racemic mixture of 9(R,S)-, 10(R,S)-, 12( R,S)- and 13(R,S)-HPODs, prepared by photooxidation and separated by NP-HPLC. The experimental results indicated that only 10( S)-HPOD isomer was cleaved by a hydroperoxide lyase activity that resulted by the for
55

The oxidation of tricarboxylic acid cycle intermediates and related compounds by Penicillium chrysogenum

Casida, Lester Earl, January 1953 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1953. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 57-58).
56

Organização do gene de pectina liase em Penicillium expansum e obtenção de linhagens recombinantes de Penicillium griseoroseum com alta produção de pectina liase / Organization of pectin lyase encoding gene from Penicillium expansum and isolation of recombinant strains of Penicillium griseoroseum with high pectin lyase production

Cardoso, Patrícia Gomes 15 March 2004 (has links)
Submitted by Nathália Faria da Silva (nathaliafsilva.ufv@gmail.com) on 2017-06-14T12:38:14Z No. of bitstreams: 1 resumo.pdf: 25134 bytes, checksum: d1f28b726d8703c03b84e1bff5ffec94 (MD5) / Made available in DSpace on 2017-06-14T12:38:14Z (GMT). No. of bitstreams: 1 resumo.pdf: 25134 bytes, checksum: d1f28b726d8703c03b84e1bff5ffec94 (MD5) Previous issue date: 2004-03-15 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / A seqüência de nucleotídeos contendo o gene ple1 que codifica pectina liase em Penicillium expansum foi clonada. Esta seqüência contém 874 nucleotídeos da região promotora, 1342 nucleotídeos da região codificadora e 469 nucleotídeos da região terminadora. A região codificadora do gene ple1 é interrompida por dois íntrons, de 101 e 116 nucleotídeos, confirmados pela seqüência do cDNA. Na seqüência da região promotora de ple1 foi observado cis-elementos envolvidos na regulação da expressão desse gene, como TATA box (TATATAA) na posição -91 do códon de início da tradução, sendo esta seqüência precedida por uma região rica em pirimidinas e CAAT box (CCAATT) a -568 do códon de inicio da tradução. A proteína PLE1, deduzida a partir da seqüência de nucleotídeos possui 374 resíduos de aminoácidos, com massa molecular estimada de 40,1 KDa e pI calculado de 9,46. Análise por hibridização do DNA total de P. expansum e P. griseoroseum com um fragmento de DNA de 2,1 Kb que corresponde ao gene pelA de A. niger, indicou organização semelhante dos genes de PL no genoma destes fungos. A expressão do gene ple1, avaliada pela hibridização do RNA total com um fragmento de DNA que corresponde à região estrutural do gene ple1 mostrou que o transcrito foi detectado durante todo tempo de cultivo em presença de pectina. No entanto, quando cultivado em presença de sacarose, o transcrito somente foi detectado em 12 e 24 horas de cultivo, com adição de extrato de levedura. A caracterização morfológica de P. expansum e P. griseoroseum mostrou diferenças nítidas tanto no diâmetro quanto na coloração do verso das colônias destes fungos. Diferenças na organização da região subtelomérica dos cromossomos de P. expansum e P. griseoroseum, foram observadas quando o plasmídeo pTEL13 foi utilizado como sonda. A região ITS do rDNA de P. expansum tem 600 pb e de P. griseoroseum 594 pb. As linhagens transformantes obtidas com os plasmídeos pPlg1 e pNPG1, apresentaram aumentos na atividade de PL de no máximo 3 vezes. Análise por hibridização do DNA total dos transformantes indicou a ocorrência de integrações homólogas e heterólogas de pelo menos duas cópias do gene plg1. Foi construído um vetor de expressão, denominado pAN52-Plg1 que continha o gene plg1 sob o controle do promotor forte constitutivo do gene (gpdA) de A. nidulans. A transformação da linhagem mutante PG63 utilizando este vetor e o pNPG1, resultou na obtenção de uma linhagem recombinante (105) com aumento de 58 vezes na atividade de PL, quando cultivada em presença de glicose como fonte de carbono. Seis linhagens recombinantes foram avaliadas por hibridização apresentando integração heteróloga de mais de uma cópia do gene plg1 no genoma. Avaliação das proteínas extracelulares por eletroforese (SDS-PAGE) mostrou a presença de uma banda nítida e forte de aproximadamente 40 KDa presente no sobrenadante de cultivo da linhagem recombinante 105 que corresponde a PLG1. A atividade específica aparente de PL sintetizada por esta linhagem foi 44 e 27 vezes maior do que aquela obtida para linhagem mutante PG63 e de uma preparação comercial de pectinases “Citrus Clear”, respectivamente. O cultivo da linhagem recombinante 105 em meio contendo caldo de cana promoveu uma atividade de PL 132 vezes maior do que a atividade obtida pela linhagem PG63 cultivada nesta mesma fonte de carbono. A atividade de PL da linhagem recombinante 105, cultivada em diferentes volumes de meio, aumentou linearmente com o tempo. Pectina cítrica, quando utilizada como substrato, promoveu maior atividade de PL. A enzima mostrou ser estável em ampla faixa de pH e temperatura de armazenamento. Estes resultados mostram que a linhagem recombinante 105 é promissora para produção de PL em escala industrial, principalmente, para aplicação na indústria de sucos e vinhos, onde o emprego apenas da PL apresenta várias vantagens na qualidade do produto final. / The sequence of the pectin lyase-enconding gene ple1, from Penicillium expansum, was cloned. This sequence consists of 874 nucleotides of the promoter region, 1342 nucleotides of the coding region, and 469 nucleotides of the terminator region. The coding region of ple1 is interrupted by two introns of 101 and 116 nucleotides, confirmed by cDNA sequencing. Two cis-elements, TATA box (TATATAA) and CAAT box (CCAATT), were found at the positions 91 and 568 upstream from the translation start code, respectively. The deduced amino acid (aa) sequence (374 aa) of PLE1 has an estimated molecular mass of 40.1 KDa and a calculated pI of 9.46. One putative N- glycosylation site was found at Asn 112 . Southern blot analysis of genomic DNA from P. expansum and P. griseoroseum with a 2.1 kb-DNA fragment of the gene pelA from A. niger indicated that this gene is similarly organized in the genomes of these fungi. The hibridization of total RNA with a fragment of the coding region of ple1 showed that the transcript was detected diring the whole of cultivation in a medium containing pectin. However, when the fungus was cultivated in the presence of sucrose with addition of yeast extract, the transcript was detected only at 12 and 24 hours of cultivation. The morphologic characterization of P. expansum and P. griseoroseum showed clear differences in the xdiameter and in the coloration of the botton of the colonies. Differences in the organization of the subtelomeric region of chromosomes of P. expansum and P. griseoroseum, were observed when the plasmid pTEL13 was used as a probe. The ITS region of the rDNA of P. expansum has 600 bp and that of P. griseoroseum 594 bp. The transformants obtained with the plasmids pPlg1 and pNPG1 presented increases in the activity of PL of at the least 3 times the active of the wild type. The hibridization profile of the genomic DNA of the transformants showed the occurrence of homologous and heterologous integrations of at least two additional copies of the gene plg1 in the genome. It was not possible to define the exact number of copies and correlate it with PL activity. An expression vector was built, designated pAN52-Plg1 that contained the gene plg1 under the control of the strong constitutive promoter gpdA of A. nidulans. The transformation of the mutant strains PG63 using this vector and the pNPG1 resulted in the isolation of a recombinant strain (105) with a PL activity 58 times higher than that of the wild type, when cultivated in glucose as the sole carbon source. Six recombinants were analised by hybridization that presented heterologous integration of more than one copy of plg1. Evaluation of the extracellular proteins by electrophoresis (SDS-PAGE) showed the presence of a clear and strong band of approximately 40 KDa in the cultivation filtrate of the recombinant 105. This band corresponded to PLG1. The apparent specific activity of PL synthesized by this strain was 44 and 27 times higher than that obtained for the strain PG63 and for a commercial preparation of pectinolytic enzymes (Citrus Clear), respectively. The cultivation of the recombinant strain 105 in a medium containing sugar cane juice promoted a PL activity that was 132 times higher than that for the strain PG63 cultivated with the carbon source. PL activity of the recombinant strain 105, cultivated in different volumes of medium, increased linearly with time. Citric Pectin, when used as substrate, supported higher PL activity. The enzyme was stable in a wide range of pH and storage temperature.
57

Estudo químico e biológico dos fungos endofílicos associados com a espécie vegetal Alibertia macrophylla (Rubiaceae)

Oliveira, Camila Martins de [UNESP] 17 April 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-04-17Bitstream added on 2014-06-13T20:06:36Z : No. of bitstreams: 1 oliveira_cm_dr_araiq.pdf: 6887141 bytes, checksum: 82b00c7d4674c3606654ce87230ecfce (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este trabalho, descreve a busca de substâncias bioativas a partir do estudo químico e biológico dos extratos brutos produzidos pelos fungos endofíticos AM-01 identificado como Penicillium sp1, AM-02 e AM-03 não identificados e AM-04, também pertencente ao gênero Penicillium, que foram isolados das folhas de Alibertia macrophylla. Os fungos endofíticos isolados, foram cultivados em meio líquido MBD, e sólido (milho) a 25oC, sob agitação, e no modo estático, respectivamente. Para o meio líquido, o caldo foi separado do micélio e submetido à partição com AcOEt, fornecendo os extratos brutos após a evaporação do solvente. Para o meio sólido, foi realizado uma extração com metanol, seguido de filtração e evaporação do solvente, originando os extratos brutos. Após análises por RMN de ¹H e CLAE-DAD, os extratos brutos obtidos em milho, foram fracionados por cromatografia em coluna, seguida de separação via Cromatografia Líquida de Alta Eficiência (CLAEprep.). O extrato bruto de AM-01 (Penicillium sp1) forneceu seis substâncias da classe das isocumarinas, sendo duas inéditas. O fracionamento cromatográfico do extrato bruto de AM-02, conduziu ao isolamento de três sesquiterpenos inéditos identificados como Xylarenonas C, D e E. Também do extrato bruto de AM-02 foi isolado um composto furânico identificado como (E)-5-(1- hidroxialil)-4-(pent-1-enil)-2,5-diidrofurano-3-ácido carboxílico. O fracionamento cromatográfico de AM-04, permitiu o isolamento de um benzenóide, identificado como orcinol. O estudo químico dos extratos brutos obtidos em MBD, de AM-03 e AM-04, permitiram o isolamento das dicetopiperazinas ciclo (Pro-Try) e ciclo (L-Pro- L-Val), além da uracila. As substâncias isoladas foram identificadas por análises de RMN 1D e 2D e espectrometria de massas, bem como por comparação com dados da literatura... / This work describes the search for bioactive substances from the chemical/biological of the crude extracts produced by endophytic fungi AM-01 identified as Penicillium sp1, AM-02, AM-03 and AM-04 also belonging to the genus Penicillium isolated from the leaves of Alibertia macrophylla. The endophytic fungal isolates were grown in liquid medium and solid MBD to 25 °C under shaking and static mode, respectively. For the liquid medium the mycelium was separated from the broth and subjected to partition with AcOEt, giving the crude extracts after evaporation of the solvent. For solid medium, the extraction was performed with MeOH, followed by filtration and evaporation of the solvent yielding the crude extracts. After analysis by the ¹H NMR and HPLC-DAD, the crude extracts from maize were fractionated by chromatography on a column followed by separation using High Performance Liquid Chromatography (HPLCprep.). The crude extract of AM-01 (Penicillium sp1) provided six isocoumarins, two news. Chromatographic fractionation of the crude extract of AM-02 led to the isolation of three novel sesquiterpenes identified as Xylarenonas C, D and E and a furanic compound identified as 2,5-dihydro-5-(1-hydroxyallyl)-4-(E)-pent-1-enyl)furan-3-carboxylic acid. Chromatographic fractionation of AM-04 allowed the isolation of a benzenoid, identified as orcinol. The chemical study of AM-03 crude extracts and AM-04 cultivated in MDB allowed the isolation of diketopiperazines cyclo (Pro-Try), cyclo (L-Pro-L-Val), and uracil. The substances isolated were identified through analysis of 1H NMR, mass spectrometry and by comparison with literature data. The crude extracts and pure substances were submited for trials for antifungal agents, antioxidants, anticholinesterasic and inhibition of protease. All substances showed biological activities.
58

Fusão de protoplastos entre Penicillium echinulatum e Trichoderma harzianum para obtenção de variabilidade visando a produção de celulases

Souza, Bárbara Lizandra Perini de 27 November 2007 (has links)
O estudo de fungos celulolíticos tem-se mostrado relevante, tendo em vista o interesse econômico do complexo celulases, especialmente na indústria têxtil e, mais recentemente, para propósitos energéticos. No presente trabalho, a fusão de protoplastos foi utilizada para combinar genótipos de mutantes parcialmente desreprimidos para produção de celulases de Penicillium echinulatum (9A02S1B9) e richoderma harzianum (AS5CH3), utilizando a técnica do doador morto, buscando-se obter recombinantes com maior produção de celulases. Nesta estratégia, ambas as linhagens tiveram seu micélio tratado com Glucanex 0,01 g/mL, para quebra da parede celular. Os protoplastos resultantes da linhagem portadora de marca de resistência ao benomil (9A02S1B9) foram inativados por calor (técnica do doador morto) de 60oC antes da etapa de fusão, a qual após foi induzida por PEG4000 e Ca2+, com protoplastos da linhagem sensível ao benomil (AS5CH3). A partir de um produto de fusão, foram selecionados 24 sub-clones, após estratégias de estabilização e seleção para precocidade e eficiência na formação de halo de hidrólise de celulose em placas de Petri. Os produtos de fusão apresentaram morfologia e esporulação semelhantes a um dos parentais, sendo treze semelhantes à Penicillium, nove semelhantes à Trichoderma e dois mostrando formas alteradas. Os produtos de fusão que segregaram para morfologia de T. harzianum apresentaram a característica de resistência ao benomil, sendo capazes de crescer e esporular em meios contendo até 100 μg/mL deste inibidor. A morfologia, o perfil de bandas, obtidos por RAPD, e o padrão de secreção de celulases dos produtos de fusão foram sempre mais semelhantes a um dos parentais. Os clones apresentaram variação quanto ao halo de hidrólise de celulose em placas de Petri e na atividade sobre papel filtro FPAases, -glicosidase ou endoglicanase, quando crescidas em cultivo submerso ou em estado sólido. Desta variabilidade, verificaram-se aumentos significativos para algumas das linhagens em relação aos parentais. A aplicação da metodologia de fusão de protoplastos para obter recombinantes entre P. echinulatum e T. harzianum, empregando a técnica do doador morto, mostrou-se adequada na geração de variabilidade para produção de celulases. / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2015-02-12T12:22:13Z No. of bitstreams: 1 Dissertacao Barbara Lizandra Perini de Souza.pdf: 2248330 bytes, checksum: 2a20339f50d031a74d2a889ddbe2435e (MD5) / Made available in DSpace on 2015-02-12T12:22:13Z (GMT). No. of bitstreams: 1 Dissertacao Barbara Lizandra Perini de Souza.pdf: 2248330 bytes, checksum: 2a20339f50d031a74d2a889ddbe2435e (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The study of cellulolytic fungi has proved to be important, considering economic interest of the cellulase complex, especially in the textile industry and, more recently, for energy purposes. In this work, the protoplast fusion was used to combine genotypes of mutants partially non repressed for cellulases production of Penicillium echinulatum (9A02S1B9) and Trichoderma harzianum (AS5CH3) using the technique dead donor, intending to obtain recombinants with higher cellulases production. In this strategy, both strains had their mycelium treated with Glucanex  0,01 g/mL, to lyse the cell wall. The protoplast obtained from the benomyl-resistant (9A02S1B9) were heat-inactivated (technique of dead donor) at 60ºC, before the step of fusion, induced by PEG4000 and Ca2+, with protoplast of the sensitive-benomyl strain (AS5CH3). Twenty four sub-clones were selected from one fusion product, after stabilization and selection strategies for precocity and efficiency in the formation clearing zones of by cellulose hydrolysis in Petri plates. The fusion products showed similar morphology and sporulation to one of parents, thirteen similar to Penicillium, nine similar to Trichoderma and two showed altered forms. The fusion products which segregate to the morphology of T. harzianum resistance to benomyl, being able to grow and sporulate in media containing up to 100 μg/mL of this inhibitor. The morphology, the profile of bands, obtained by RAPD, and the pattern of cellulase secretion by fusion products were ever more similar to one of parents. The fusants presented variation in the halo of cellulose hydrolysis in Petri plates, and in the activity on filter paper (FPAases), - glicosidase or endoglicanase, when grown submerged cultivation or solid state. From this variability, significant improvement was verified for some of the parental strains. The application of the protoplast fusion methodology to obtain recombinant between P. echinulatum and T. harzianum, using the technique of dead donor, has proved to be adequate to generate variability in the production of cellulases.
59

Secretômica e atividades enzimáticas da linhagem selvagem 2HH e do mutante S1M29 de Penicillium echinulatum

Schneider, Willian Daniel Hahn 05 December 2014 (has links)
O emprego de enzimas lignocelulolíticas secretadas por microrganismos para a produção de etanol de segunda geração tem motivado pesquisas na área da engenharia de processos fermentativos, genômica e secretômica. Entre os microrganismos com potencial para a produção de celulases destacam-se variantes genéticos do fungo filamentoso Penicillium echinulatum caracterizados por produzirem altos títulos enzimáticos. Neste trabalho, estudouse a secretômica da linhagem selvagem 2HH e do mutante S1M29 de P. echinulatum, em cultivo submerso, empregando diferentes fontes de carbono: glicose, glicerol, celulose e bagaço de cana-de-açúcar pré-tratado por explosão a vapor. Análises enzimáticas possibilitaram identificar que P. echinulatum produz celulases, hemicelulases, esterases e, em menor proporção, pectinases e amilases. Outrossim, os maiores títulos enzimáticos para a maioria das enzimas foram verificados na linhagem mutante. Nos meios formulados com bagaço de cana-de-açúcar ou celulose verificou-se a indução das maiores produções enzimáticas para ambas as linhagens. A análise do secretoma por 1D-PAGE seguido de LCMS/ MS das amostras de 96 horas de cultivo permitiu identificar que em ambas as linhagens há predominância de enzimas CAZy, sendo celulases, hemicelulases e enzimas degradadoras de parede celular fúngica as mais predominantes. Celobiohidrolases, endoglicanases, β-glicosidases, xilanases, β-xilosidases e mananases foram identificadas e, em quantidades menores, ligninases, pectinases, amilases, esterases e solenina, entre outras proteínas (adesão, chaperonas, oxidoredutases, proteases, peptidases, lipases, glutaminases e hipotéticas). Os meios elaborados com glicose ou glicerol foram utilizados pelo fungo para a produção de amilases, ligninases e enzimas degradadoras da parede celular fúngica. Destaca-se a secreção 2 a 3 vezes maior de celulases pela linhagem mutante, sendo que o meio de cultivo elaborado com bagaço de cana-de-açúcar proporcionou a secreção de maiores quantidades de celulases para o mutante. Nesta condição, o complexo celulolítico da linhagem S1M29 constitui-se de 55% de celobiohidrolases, 38% de endoglicanases e 1% de β-glicosidases. Estes dados sugerem que durante o melhoramento genético do fungo ocorreram mudanças, embora não direcionais, possivelmente em nível da regulação da expressão gênica, modificações póstraducionais e alterações na capacidade para secretar proteínas extracelulares que tornaram a linhagem mutante S1M29 com potencial para ser empregada na hidrólise de lignocelulósicos. / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2015-02-12T12:51:30Z No. of bitstreams: 1 Dissertacao Willian Daniel Hahn Schneider.pdf: 2455680 bytes, checksum: 6b4ce5e7e2a0bd9fc7714d8979b4ee29 (MD5) / Made available in DSpace on 2015-02-12T12:51:30Z (GMT). No. of bitstreams: 1 Dissertacao Willian Daniel Hahn Schneider.pdf: 2455680 bytes, checksum: 6b4ce5e7e2a0bd9fc7714d8979b4ee29 (MD5) / The use of lignocellulolytic enzymes secreting by microorganisms for the production of second-generation ethanol has motivated research in the field of fermentation processes engineering, genomics and secretomics. Among the microorganisms with the potential for cellulases production are genetic variants of the filamentous fungus Penicillium echinulatum characterized by produce high enzymatic titers. In this work, it was studied the secretome of the wild type 2HH and mutant S1M29 of P. echinulatum in submerged cultivation on different carbon sources: glucose, glycerol, cellulose and sugar cane bagasse pretreated by steam explosion). Enzymatic analysis allowed verifying that P. echinulatum produces cellulases, hemicellulases, esterases, and minor proportion, pectinases and amylases. Furthermore, the major enzymes titers for most enzymes dosed were verified in the mutant strain. It was verified in the media formulated with sugar cane bagasse or cellulose the induction of the highest enzyme production for both strains. The analysis of secretome by 1DPAGE followed by LC-MS/MS, of samples collected at 96 hours of cultivation, showed that in both strains there is a predominance of CAZy enzymes, being cellulases, hemicellulases and fungal cell wall degrading enzymes the most prevalent. Cellobiohydrolases, endoglucanases, β-glucosidase, xylanase, endoxylanase, β-mannanases and xylosidases were identified and, in smaller amounts, ligninases, pectinases, amylases, esterases and swollenin, among other proteins (adhesion, chaperones, oxidoreductases, proteases, peptidases, lipases, glutaminases and hypothetical). The media elaborated with glucose or glycerol were used for producing of amylases, ligninases and fungal cell wall degrading enzymes. Highlights the secretion of 2-3 times more cellulases by the mutant, being the medium prepared with sugar cane bagasse afforded the secretion of large cellulases quantities for the mutant. In this condition, the cellulolytic complex of S1M29 strain consists of 55% cellobiohydrolases, 38% endoglucanases and 1% β-glucosidase. These data suggest that during the genetic improvement of the fungus changes occurred, although not directional, possibly at the level of regulation of gene expression, post-translational modifications and changes in the ability to secrete extracellular proteins, that have made the mutant S1M29 a potential strain to be employed in hydrolysis of lignocellulose.
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Efeito da adsorção e filtração na produção de celulases e xilanases

Ritter, Carla Eliana Todero 02 June 2015 (has links)
Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2015-10-01T16:43:18Z No. of bitstreams: 1 Tese Carla Eliana Todero Ritter.pdf: 192233 bytes, checksum: 7751f00ffe27681835ffe3c324f029fa (MD5) / Made available in DSpace on 2015-10-01T16:43:18Z (GMT). No. of bitstreams: 1 Tese Carla Eliana Todero Ritter.pdf: 192233 bytes, checksum: 7751f00ffe27681835ffe3c324f029fa (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPES.

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