Produção de β-glucanases por Trichoderma reesei e Trichoderma harzianum e aplicação na hidrólise de β-glucanas

Pós-graduação em Ciências Biológicas (Microbiologia Aplicada) - IBRC

Produção, isolamento e caracterização de 'beta'-galactosidades de Trichoderma reesei: interação de íons metálicos na atividade enzimática

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Control of lettuce bottom rot by isolates of Trichoderma spp

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Production of β-(1,3)-glucanases by Trichoderma harzianum Rifai: Optimization and Application to Produce Gluco-oligosaccharides from Paramylon and Pustulan

β-(1→3)-Glucanases were produced by Trichoderma harzianum Rifai PAMB-86 cultivated on botryosphaeran in a bench-fermenter and optimised by the response surface method. Maximal enzyme titres occurred at 5 days, initial pH 5.5 and aeration of 1.5vvm. β-(1→3)-The β-glucanolytic enzyme complex produced by T. harzianum Rifai PAMB- 86 was fractionated by gel filtration into 2 fractions (F-I, F-II), and employed to produce gluco-oligosaccharides from algal paramylon ((1→3)-β-D-glucan) and lichen pustulan ((1→6)-β-D-glucan). Both enzymes attacked paramylon to the extent of ~15-20% in 30 min releasing glucose and laminaribiose as major end-products, and laminarioligosaccharides of degree of polymerization (DP) ≥3. Only F-I degraded pustulan resulting in ~2% degradation at 30 min, with glucose, gentiobiose and gentio-oligosaccharides of DP ≥4 as major products. The difference in the nature of the hydrolysis products can be explained by the substrate specificities of each enzyme fraction, and the structural differences of the β-D-glucans attacked.

Seleção de micro-organismos celulolíticos comparados com o Trichoderma reesei CCT 2768

As celulases atualmente são enzimas extensivamente estudadas para a hidrólise de resíduos lignocelulósicos para obtenção de açúcares fermentescíveis utilizáveis em diferentes processos biotecnológicos, como a produção de bioetanol. O objetivo deste trabalho foi encontrar fungos celulolíticos que sejam eficientes nos processos de degradação da biomassa lignocelulósica. No presente trabalho foram selecionados 4 fungos celulolíticos previamente isolados pelo Laboratório de Biotecnologia Industrial (UNESP – Assis). Estes fungos foram cultivados em bagaço de cana-de-açúcar como substrato e para seus extratos enzimáticos foram testados suas atividades para celulases (FPase) e endoglucanases (CMCase). Os fungos FS09 (0,054 FPU/mL e 1,79 FPU/g de substrato, 0,874 U/mL e 29,1 U/g de substrato) e M51 (0,049 FPU/mL e 1,62 FPU/g de substrato, 1,094 U/mL e 36,46 U/g de substrato), mostrando valores superiores ao fungo T.reesei CCT 2768 que é referência em estudos e produção de celulases.

Produção de enzimas celulolíticas pelos fungos Trichoderma reesei e Myceliophthora thermophila e aplicação na sacarificação do bagaço de cana-de-açucar

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação de isolados de Trichoderma spp. para controle de Phytophthora nicotianae

Pós-graduação em Microbiologia Agropecuária - FCAV

Unraveling Trichoderma species in attine ant environment: description of three new taxa

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Produção de enzimas lignocelulósicas por fermentação em estado sólido por espécimes do gênero Trichoderma para sacarificação do bagaço de cana de açúcar tratado com micro-ondas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Produção de enzimas lignocelulósicas por fermentação em estado sólido por espécimes do gênero Trichoderma para sacarificação do bagaço de cana de açúcar tratado com micro-ondas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Marine Fungi Aspergillus sydowii and Trichoderma sp Catalyze the Hydrolysis of Benzyl Glycidyl Ether

Whole cells of the marine fungi Aspergillus sydowii Gc12, Penicillium raistrickii Ce16, P. miczynskii Gc5, and Trichoderma sp. Gc1, isolated from marine sponges of the South Atlantic Ocean (Brazil), have been screened for the enzymatic resolution of (+/-)-2-(benzyloxymethyl)oxirane (benzyl glycidyl ether; 1). Whole cells of A. sydowii Gc12 catalyzed the enzymatic hydrolysis of (R,S)-1 to yield (R)-1 with an enantiomeric excess (ee) of 24-46% and 3-(benzyloxy)propane-1,2-diol (2) with ee values < 10%. In contrast, whole cells of Trichoderma sp. Gc1 afforded (S)-1 with ee values up to 60% and yields up to 39%, together with (R)-2 in 25% yield and an ee of 32%. This is the first published example of the hydrolysis of 1 by whole cells of marine fungi isolated from the South Atlantic Ocean. The hydrolases from the two studied fungi exhibited complementary regioselectivity in opening the epoxide ring of racemic 1, with those of A. sydowii Gc12 showing an (S) preference and those of Trichoderma sp. Gc1 presenting an (R) preference for the substrate.

Effect of pH and temperature on the global compactness, structure, and activity of cellobiohydrolase Cel7A from Trichoderma harzianum

Due to its elevated cellulolytic activity, the filamentous fungus Trichoderma harzianum (T. harzianum) has considerable potential in biomass hydrolysis application. Cellulases from Trichoderma reesei have been widely used in studies of cellulose breakdown. However, cellulases from T. harzianum are less-studied enzymes that have not been characterized biophysically and biochemically as yet. Here, we examined the effects of pH and temperature on the secondary and tertiary structures, compactness, and enzymatic activity of cellobiohydrolase Cel7A from T. harzianum (Th Cel7A) using a number of biophysical and biochemical techniques. Our results show that pH and temperature perturbations affect Th Cel7A stability by two different mechanisms. Variations in pH modify protonation of the enzyme residues, directly affecting its activity, while leading to structural destabilization only at extreme pH limits. Temperature, on the other hand, has direct influence on mobility, fold, and compactness of the enzyme, causing unfolding of Th Cel7A just above the optimum temperature limit. Finally, we demonstrated that incubation with cellobiose, the product of the reaction and a competitive inhibitor, significantly increased the thermal stability of Th Cel7A. Our studies might provide insights into understanding, at a molecular level, the interplay between structure and activity of Th Cel7A at different pH and temperature conditions.

Trichoderma harzianum expressed sequence tags for identification of genes with putative roles in mycoparasitism against Fusarium solani

The plant pathogen Fusarium solani causes a disease root rot of common bean (Phaseolus vulgaris) resulting in great losses of yield in irrigated areas of the Southeast and Midwest regions of Brazil. Species of the genus Trichoderma have been used in the biological control of this pathogen as an alternative to chemical control. To gain new insights into the biocontrol mechanism used by Trichoderma harzianum against the phytopathogenic fungus, Fusarium solani, we performed a transcriptome analysis using expressed sequence tags (ESTs) and quantitative real-time PCR (RT-qPCR) approaches. A cDNA library from T. harzianum mycelium (isolate ALL42) grown on cell walls of F. solani (CWFS) was constructed and analyzed. A total of 2927 high quality sequences were selected from 3845 and 37.7% were identified as unique genes. The Gene Ontology analysis revealed that the majority of the annotated genes are involved in metabolic processes (80.9%), followed by cellular process (73.7%). We tested twenty genes that encode proteins with potential role in biological control. RT-qPCR analysis showed that none of these genes were expressed when T. harzianum was challenged with itself. These genes showed different patterns of expression during in vitro interaction between T. harzianum and F. solani. (C) 2012 Elsevier Inc. All rights reserved.

Crystallization and preliminary X-ray diffraction analysis of endoglucanase III from Trichoderma harzianum

Endoglucanases are enzymes that hydrolyze cellulose and are important components of the cellulolytic complex. In contrast to other members of the complex, they cleave internal beta-1,4-glycosidic bonds in the cellulose polymer, allowing cellulose to be used as an energy source. Since biomass is an important renewable source of energy, the structural and functional characterization of these enzymes is of interest. In this study, endoglucanase III from Trichoderma harzianum was produced in Pichia pastoris and purified. Crystals belonging to the orthorhombic space group P212121, with unit-cell parameters a = 47.54, b = 55.57, c = 157.3 angstrom, were obtained by the sitting-drop vapour-diffusion method and an X-ray diffraction data set was collected to 2.07 angstrom resolution.