Development and Biotechnological Application of a Novel Endoxylanase Family GH10 Identified from Sugarcane Soil Metagenome

Metagenomics has been widely employed for discovery of new enzymes and pathways to conversion of lignocellulosic biomass to fuels and chemicals. In this context, the present study reports the isolation, recombinant expression, biochemical and structural characterization of a novel endoxylanase family GH10 (SCXyl) identified from sugarcane soil metagenome. The recombinant SCXyl was highly active against xylan from beechwood and showed optimal enzyme activity at pH 6,0 and 45°C. The crystal structure was solved at 2.75 Å resolution, revealing the classical (β/α)8-barrel fold with a conserved active-site pocket and an inherent flexibility of the Trp281-Arg291 loop that can adopt distinct conformational states depending on substrate binding. The capillary electrophoresis analysis of degradation products evidenced that the enzyme displays unusual capacity to degrade small xylooligosaccharides, such as xylotriose, which is consistent to the hydrophobic contacts at the +1 subsite and low-binding energies of subsites that are distant from the site of hydrolysis. The main reaction products from xylan polymers and phosphoric acid-pretreated sugarcane bagasse (PASB) were xylooligosaccharides, but, after a longer incubation time, xylobiose and xylose were also formed. Moreover, the use of SCXyl as pre-treatment step of PASB, prior to the addition of commercial cellulolytic cocktail, significantly enhanced the saccharification process. All these characteristics demonstrate the advantageous application of this enzyme in several biotechnological processes in food and feed industry and also in the enzymatic pretreatment of biomass for feedstock and ethanol production. © 2013 Alvarez et al.

Deciphering the synergism of endogenous glycoside hydrolase families 1 and 9 from Coptotermes gestroi

Termites can degrade up to 90% of the lignocellulose they ingest using a repertoire of endogenous and symbiotic degrading enzymes. Termites have been shown to secrete two main glycoside hydrolases, which are GH1 (EC 3.2.1.21) and GH9 (EC 3.2.1.4) members. However, the molecular mechanism for lignocellulose degradation by these enzymes remains poorly understood. The present study was conducted to understand the synergistic relationship between GH9 (CgEG1) and GH1 (CgBG1) from Coptotermes gestroi, which is considered the major urban pest of São Paulo State in Brazil. The goal of this work was to decipher the mode of operation of CgEG1 and CgBG1 through a comprehensive biochemical analysis and molecular docking studies. There was outstanding degree of synergy in degrading glucose polymers for the production of glucose as a result of the endo-β-1,4-glucosidase and exo-β-1,4-glucosidase degradation capability of CgEG1 in concert with the high catalytic performance of CgBG1, which rapidly converts the oligomers into glucose. Our data not only provide an increased comprehension regarding the synergistic mechanism of these two enzymes for cellulose saccharification but also give insight about the role of these two enzymes in termite biology, which can provide the foundation for the development of a number of important applied research topics, such as the control of termites as pests as well as the development of technologies for lignocellulose-to-bioproduct applications. © 2013 Elsevier Ltd.

Levantamento florístico d sub-bosque do morro São João Batista, Cananéia, SP

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Repórter-cronista: jornalismo e literatura na interface de João Antônio com Lima Barreto

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

As relações no processo de montagem cinematográfica entre os filmes Um homem com uma câmera e Koyaanisqatsi

Pós-graduação em Comunicação - FAAC

A concepção de criança e desenvolvimento infantil e a coleção Biblioteca de Educação: uma análise das obras escritas pelos psicólogos funcionalistas franco-genebrinos e por Lourenço Filho

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

O ensino de língua portuguesa no Brasil, segundo João Wanderley Geraldi

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A arquitetura da criação: um estudo de Mínimos, múltiplos, comuns, de João Gilberto Noll

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

Da forma à substância: a percepção tátil da figura feminina em alguns poemas de Quaderna de João Cabral de Melo Neto

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A construção da imagem em O Espelho in Primeira estórias de João Guimarães Rosa e em Las meninas de Pablo Picasso

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Fora do palco, dentro da vida: o contista Arthur Azevedo e o Rio de Janeiro de sua época

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

O módulo de jogos no Colégio de Aplicação João XXIII: um estudo de caso

Pós-graduação em Educação - FCT

Zoneamento geoambiental do município de São João da Boa Vista (SP)

Pós-graduação em Geociências e Meio Ambiente - IGCE

Evolução metamórfica (P-T-t) de granulitos e migmatitos do Complexo Guaxupé na região de São João da Boa Vista, SP

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A representação do sertão na metrópole: a construção de um gênero musical (1929-1940)

Pós-graduação em História - FCHS