Banca de DEFESA: ALINE CARDOSO CARLOS

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : ALINE CARDOSO CARLOS
DATA : 31/01/2019
HORA: 14:00
LOCAL: Sala Carl Von Dietrich
TÍTULO:

PROSPECTION OF MICRORGANISMS AND GENES INVOLVED IN THE BIODEGRADATION OF PETROLEUM AND DERIVATIVES

PALAVRAS-CHAVES:

metagenomic libraries, bioremediation, degradation hydrocarbons

PÁGINAS: 96
GRANDE ÁREA: Ciências Biológicas
ÁREA: Bioquímica
SUBÁREA: Bioquímica dos Microorganismos
RESUMO:

 Industrial activities generated by oil exploration have generated a lot of waste. The waste generated represents a major environmental liability, which requires adequate treatment. In this way, the development of environmental bioremediation strategies has been increasing in recent years. In this context, the metagenomic approach was used in the present work to identify microorganisms and genes associated with hydrocarbon biodegradation and biosurfactant synthesis, from the functional screening of the metagenomic library and the isolation of bacteria. A metagenomic library using environmental DNA from the oil well drilling fluid residue was constructed and the clones obtained in plasmid (pBC) and expressed in E. coli (DH10B). Clones were functionally screened. For this, qualitative and quantitative tests were used, such as the colorimetric test based on the reduction of DCPIP (2,6-dichlorophenol indophenol), which allows the detection of hydrocarbon degradation. The DCPIP test revealed 60 clones positive for degradation activity, of which 25 were sequenced. The prediction of ORFs allowed the identification of genes involved in the degradation pathways of aliphatic and aromatic hydrocarbons. Growth of the clones in the presence of petroleum, corroborated with the results obtained in the DCPIP test, revealing ability of degradation by the clones. Six clones showed degradation estimates between 50 and 80% when compared to E.coli DH10BØ (host strain with empty vector). These six clones were selected for assembly of two consortia (C consortium and C + I consortium) which were used for bioremediation of the drilling fluid residue. In this study, high metabolic activity during the monitored period (28 days) was observed through the dehydrogenase activity. The degradation rates were 14 and 42% of n-alkanes for the C and C + I consortia, respectively, suggesting the potential of the consortia to be applied in bioremediation processes in oil contaminated environments. Sequencing of the consortium forming clones showed the presence of genes involved in different pathways as well as key genes involved in the degradation of aliphatic and aromatic hydrocarbons. Bacteria isolated from the residue were identified by sequencing the 16S rRNA and showed high identity with representatives of the genus Brevibacillus and Bacillus. The functional approach of metagenomic libraries used in the present work has proved to be an excellent strategy for the prospection of enzymes active in the degradation of petroleum hydrocarbons.

MEMBROS DA BANCA:
Externa à Instituição - ANA LÚCIA FIGUEIREDO PORTO - UFRPE
Externo à Instituição - DEMETRIUS ANTONIO MACHADO DE ARAÚJO - UFPB
Externo ao Programa - 1346198 - EVERALDO SILVINO DOS SANTOS
Presidente - 1149647 - LUCYMARA FASSARELLA AGNEZ LIMA
Interna - 1674709 - VIVIANE SOUZA DO AMARAL