Banca de QUALIFICAÇÃO: Raul Alcântara Teixeira Lima

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : Raul Alcântara Teixeira Lima
DATE: 23/02/2023
TIME: 08:00
LOCAL: Auditório Maristela
TITLE:

Bioprospection of Synthermes wheeleri gut microbiome using the bacteria metagenome for mining enzymes able to convert lignocellulose into chemicals with a high added value.

KEY WORDS:

Bioprospecting, lignocellulose, metagenome, Syntermes wheeleri

PAGES: 121
BIG AREA: Ciências Biológicas
AREA: Biologia Geral
SUMMARY:

Termites consume approximately 3 to 7 billion tons of lignocellulosic materials per year and therefore represent one of the most prolific and efficient lignocellulose decomposers on Earth. The bioconversion of cell wall polysaccharides by termites is a highly coordinated process achieved by the gut-resident microbial symbionts. In this work we aim to use the biotechnological potential of these microorganisms to obtain enzymes able to convert the polysaccharides into chemicals with a high added value. The process was carried out with the bacterial gut metagenome of Syntermes wheeleri an endemic termite specie of Brazilian savanna (Cerrado). Here we developed an integrated bioinformatic analysis that suggested clusters of proteins in phylogenetic trees with the potential for innovation. These proteins’ domains were distributed in Glycosyl Hydrolases (GHs) - 3, 5, 9 and 10 with representatives of the phyla Firmicutes, Proteobacteria, Bacteroidetes and Spirochaeta, among others. With the goal to characterize and evaluate the biotechnological potential we used E. coli BL21(DE3) and the PET plasmid systems to synthesize some of them. The biochemicals results demonstrated 40-45ºC as the best temperature of activity for Exo 85-74 (exoglucanase) and β-G 72-26 (β-glucosidase), in addition they presented acid and basic pH as the optimum pH, respectively. Circular Dichroism demonstrated the pH dependence of secondary structure according the αhelices and β-sheets quantities change. These characteristics provided the best conditions to saccharification. This process can be used in distinct biomass, as sugar cane and corn cob, using heat treatment as an environmentally friendly pre-treatment process, compared with chemical pre-treatment, to enhance the access of proteins to polysaccharides. Furthermore, FTIR (Fourier-transform infrared spectroscopy) was used to detect the before and after of biomass bioconversion by bond patterns of products. Our results will help to elucidate the capability of the selected enzymes from termite gut bacteria metagenome in biotechnology processes of lignocellulose bioconversion.

BANKING MEMBERS:
Presidente - 2222088 - ELIANE FERREIRA NORONHA
Externo à Instituição - FABYANO ALVARES CARDOSO LOPES - UFT
Externa ao Programa - 2221665 - LIDIA MARIA PEPE DE MORAES
Interno - 2644635 - ROBERT NEIL GERARD MILLER