Prospecção de genes de interesse biotecnológico : uma abordagem metagenômica

The total number of prokaryotic cells on Earth has been estimated at 4 to 6x1030 and only about 1% of microorganisms present in the environment can be cultivated by standard techniques of cultivation and plating. Therefore, it is a huge biological and genetic pool that can be exploited, for the identification and characterization of genes with biotechnological potential. Within this perspective, the metagenomics approach was applied in this work. Functional screening methods were performed aiming to identify new genes related to DNA repair and / or oxidative stress resistance, hydrocarbon degradation and hydrolytic activities (lipase, amylase and protease). Metagenomic libraries were built utilizing DNA extracted from soil samples collected in João Câmara RN. The libraries were analyzed functionally using specific substrate containing solid medium (hydrolytic activity), supplemented with H2O2 (DNA repair and / or resistance to oxidative stress) and liquid medium supplemented with light Arabian oil (activity, degradation of hydrocarbons). After confirmation of activity and exclusion of false-positive results, 49 clones were obtained, being 2 positive for amylase activity, 22 resistant to oxidative stress generated by H2O2 and 25 clones active for hydrocarbons degradation. Analysis of the sequences showed hypothetical proteins, dienelactona hydrolase, DNA polymerase, acetyltransferase, phosphotransferase, methyltransferase, endonucleases, among other proteins. The sequence data obtained matched with the functions tested, highlighting the success of metagenomics approaches combined with functional screening methods, leading to very promising results

Estudos in silico da proteína AlkB e prospecção de bactérias alcanotróficas em solos da bacia petrolífera potiguar

Some microorganisms from virgin ecosystems are able to use petroleum it as source of carbon and energy. The knowledge of microbial biodiversity can help to reveal new metabolic systems for utilization alkanes with biotechnological importance. The aim of this study is: i) Accomplish an in silico study of the AlkB protein aimed to understand the probable mechanism involved on selectivity of alkanes in Gram positive and Gram negative bactéria. ii) prospect and analyze the response of the microbial alkanotrophics communities in soil and mangrove sediments of BPP RN and soil of Atlantic forest in the Horto Dois Irmãos Reserve area/PE using the molecular biomarker, gene alkB; with the PCR and PCR-DGGE approach