Banca de QUALIFICAÇÃO: SINARA CARLA DA SILVA ARAÚJO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : SINARA CARLA DA SILVA ARAÚJO
DATA : 20/02/2018
HORA: 09:30
LOCAL: Sala SS1 - Departamento de Biologia Celular e Genética
TÍTULO:

Prospecting and obtaining of a new biosurfactant derived from a metagenomic library.

PALAVRAS-CHAVES:

Metagenomic, biosurfactant, bioremediation 

PÁGINAS: 62
GRANDE ÁREA: Ciências Biológicas
ÁREA: Bioquímica
RESUMO:

Microorganisms have an immense genetic diversity and are present in every ecosystem, however it is estimated that only 1 % of species can be cultivated by standard laboratory techniques. Within this diversity there is an enormous genetic and biological pool to be explored. Metagenomics made it possible to directly access microbial genome derived from environmental samples. This methodology allows to obtain functional information of proteins, as well as identification of potential products with biotechnological interest and of new biologically exploitable biological resources, such as new solutions for environmental impacts. Areas contaminated with petroleum are characterized by a large accumulation of hydrocarbons and surfactants are used as coadjuvants in bioremediation. Thus, metagenonomic approach was used to select genes involved in hydrocarbon degradation and emulsification process. In a previous work, environmental DNA (eDNA) was extracted from a soil collected in a saline river of Rio Grande do Norte (Brazil), metagenomic library was constructed and functionally analyzed. Clones capable of degrading oil were evaluated for ability to synthesize biosurfactant. A clone named 3C6 was sequenced and analyzed, revealing an ORF of 897 bp, 298 amino acids, relative to a protein of molecular weight close to 32 kDa. The search for homology in GenBank shown similarity to sequence encoding a hypothetical protein from representatives of Halobacteriaceae family, which were recently shown to produce biosurfactants. Presence of inserted coding sequence and acquired phenotype were confirmed. Primers were drawn and their ORFs amplified by PCR. Emulsification test was positive for different hydrocarbon sources, such as kerosene, toluene, xylene, hexadecane and hexane. The biosurfactant was partially purified through acid precipitation, also presenting emulsifying activity, besides positives results for reduction of interfacial tension, drop collapse and dispersion of oil. This study was second to report a possible protein with biosurfactant activity obtained from a metagenomic approach.

MEMBROS DA BANCA:
Presidente - 1549705 - ADRIANA FERREIRA UCHOA
Interno - 1149356 - ELIZEU ANTUNES DOS SANTOS
Externo ao Programa - 2170415 - JORGE ESTEFANO SANTANA DE SOUZA