The Secretome ofPhanerochaete chrysosporiumandTrametes versicolorGrown in Microcrystalline Cellulose and Use of the Enzymes for Hydrolysis of Lignocellulosic Materials

Autor(es)

Machado, Angela S. ^[1] ; Valadares, Fernanda ^[1] ; Silva, Tatiane F. ^[1] ; Milagres, Adriane M. F. ^[1] ; Segato, Fernando ^[1] ; Ferraz, Andre ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Biotecnol, Escola Engn Lorena, Lorena - Brazil

• Tipo de documento: Artigo Científico
• Fonte: FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY; v. 8, JUL 17 2020.
• Citações Web of Science: 0

Resumo

The ability of white-rot fungi to degrade polysaccharides in lignified plant cell walls makes them a suitable reservoir for CAZyme prospects. However, to date, CAZymes from these species are barely studied, which limits their use in the set of choices for biomass conversion in modern biorefineries. The current work joined secretome studies of two representative white-rot fungi,Phanerochaete chrysosporiumandTrametes versicolor, with expression analysis of cellobiohydrolase (CBH) genes, and use of the secretomes to evaluate enzymatic conversion of simple and complex sugarcane-derived substrates. Avicel was used to induce secretion of high levels of CBHs in the extracellular medium. A total of 56 and 58 proteins were identified in cultures ofP. chrysosporiumandT. versicolor, respectively, with 78-86% of these proteins corresponding to plant cell wall degrading enzymes (cellulolytic, hemicellulolytic, pectinolytic, esterase, and auxiliary activity). CBHI predominated among the plant cell wall degrading enzymes, corresponding to 47 and 34% of the detected proteins inP. chrysosporiumandT. versicolor, respectively, which confirms that Avicel is an efficient CBH inducer in white-rot fungi. The induction by Avicel of genes encoding CBHs (cel) was supported by high expression levels ofcel7Dandcel7C inP. chrysosporiumandT. versicolor, respectively. Both white-rot fungi secretomes enabled hydrolysis experiments at 10 FPU/g substrate, despite the varied proportions of CBHs and other enzymes present in each case. When low recalcitrance sugarcane pith was used as a substrate,P. chrysosporiumandT. versicolorsecretomes performed similarly to Cellic(R)CTec2. However, the white-rot fungi secretomes were less efficient than Cellic(R)CTec2 during hydrolysis of more recalcitrant substrates, such as acid or alkaline sulfite-pretreated sugarcane bagasse, likely because Cellic(R)CTec2 contains an excess of CBHs compared with the white-rot fungi secretomes. General comparison of the white-rot fungi secretomes highlightedT. versicolorenzymes for providing high glucan conversions, even at lower proportion of CBHs, probably because the other enzymes present in this secretome and CBHs lacking carbohydrate-binding modules compensate for problems associated with unproductive binding to lignin. (AU)

• Processo FAPESP: 14/18714-2 - Oxidação enzimática do bagaço de cana-de-açúcar: descoberta, caracterização e aplicação de novas enzimas oxidativas de carboidratos, voltadas para o desenvolvimento de um cell factory mais eficiente
• Beneficiário: Fernando Segato
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOEN - Jovens Pesquisadores
• Processo FAPESP: 14/06923-6 - Recalcitrância da biomassa de cana-de-açúcar: fundamentos relacionados à formação da parede celular, ao pré-tratamento e à digestão enzimática, aplicados no desenvolvimento de novos modelos de biorrefinarias
• Beneficiário: Andre Luis Ferraz
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOEN - Temático