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| Author(s): |
Daniela De Lucena Pedroso
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Escola de Artes, Ciências e Humanidades (EACH) |
| Defense date: | 2020-07-08 |
| Examining board members: |
Felipe Santiago Chambergo Chambergo Alcalde;
Andrezza Justino Gozzo Andreotti;
Sirlene Maria da Costa;
Roberto Kopke Salinas
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| Advisor: | Felipe Santiago Chambergo Alcalde |
| Abstract | |
The demand for renewable energy sources has encouraged research on the use of lignocellulosic biomass as a raw material for the production of 2G bioethanol, thus making it interesting to study and identify the enzymes involved in its degradation. This dissertation aims to identify the BBF-245 strain, produce, purify and characterize oxidoreductase enzymes - mainly laccases - from the fungus Pestalotiopsis sp. (BBF245) in order to evaluate the potential use of these proteins in the degradation of sugarcane bagasse and in other biotechnological applications. During the study, the identification of the strain BBF-245 (as Pestalotiopsis sp.) was carried out and the analysis of the production of oxidoreductases by the fungus in the culture in MBC medium with 1% of sugarcane bagasse, finding a greater production of laccase enzymes (2.006.7 U / mg) than manganese peroxidases (16.42 U / mg) and lignin peroxidases (106.25 U / mg), these results led to the choice of laccases for the continuation of the following stages of the work. The 4th day supernatant in MBC with 1% sugarcane bagasse was clarified and concentrated for purification in ion exchange chromatography, in which two laccases (PspLac1 and PspLac2) were obtained in the elution at 25mM and 50mM NaCl, respectively. The two enzymes were then characterized in terms of approximate molecular mass (PspLac1 = 66.7 kDa and PspLac2 = 56.3 kDa), optimum pH (PspLac1 = 3 and PspLac2 = 4), thermal stability (20-60 ° C, both), Km (PspLac1 = 15.72mM and PspLac2 = 6.42mM), kcat (PspLac1 = 18x102 s1 and PspLac2 = 5x102 s-1) and kcat.Km-1 (PspLac1 = 1.14x102 s-1.mM -1 and PspLac2 = 7.7x10 s-1.mM-1). The present work allowed the identification of BBF- 245 as Pestalotiopsis sp. and the characterization of two native laccases (PspLac1 and PspLac2), which can be used in various biotechnological applications, such as in the composition of enzymatic cocktails for the degradation of biomass (AU) | |
| FAPESP's process: | 17/25599-3 - Oxidoreductases enzymes from Pestalotiopsis SP |
| Grantee: | Daniela de Lucena Pedroso |
| Support Opportunities: | Scholarships in Brazil - Master |