Purification and characterization of glycoside hydrolases produced by the filamentous fungus Trichoderma harzianum, with perspective of applicability of these enzymes in cocktails for biomass hydrolysis and bioethanol production

Abstract

Lignocellulosic biomass such as bagasse from sugar cane, holds promises of environmentally friendly production of bioenergy in Brazil and worldwide. However, the enzymatic hydrolysis, currently considered a method of choice in the saccharification of biomass is hampered by a considerable recalcitrance of cell walls. To make this technology cost effective and sustainable, our understanding of enzymatic hydrolysis of cellulose and our ability to modify enzymes to make the processing of cellulose more efficient should be significantly improved. We propose to produce, purify and characterize the glycoside hydrolases, produced by the filamentous fungus Trichoderma harzianum, active in the process of cell wall degradation. To accomplish this task, we will use a combination of techniques such as fermentation, protein purification by HPLC, biochemical, biophysical, structural and enzymatic assays in order to obtain a deeper understanding of the process of hydrolysis by cellulases. Thus, we plan to contribute to the knowledge of the molecular organization of cellulases from Trichoderma harzianum studying biochemical and structurally these enzymes. This study is part of glycoside hydrolases research in our group and is closely linked to efforts to develop new enzyme preparations for hydrolysis of biomass in general and from sugar cane bagasse in particular. Moreover, this project is directly related to our FAPESP Thematic project (Bioen Program; process nº. 2008/56255-9 "Structure and function of enzymes and auxiliary proteins from Trichoderma, active in cell-wall hydrolysis"); to collaborative program between Brazil and European Union (CeProBIO/FP7) and will be developed in the scope of the National Institute of Science and Technology of Bioethanol (Coordinator: Prof. Marcos S. Buckeridge). We are confident that the visit of Professor Alexander Golubev will result in several scientific publications and articles in international journals of high-level as has happened during previous visits to Brazil. (AU)