Prospection and characterization of industrial interest thermostable enzymes in metagenomic and metatranscriptomic data at São Paulo Zoo Park composting facilities

Abstract

The economic interest in thermophilic microorganisms is increasing due to their ability to tolerate extreme conditions during industrial processes. The composting process in which the temperature can reach higher temperatures, as 80 °C, is a promising source of these thermostable enzymes. Article published in 2013 showed that the composition of the composting's microbiota at the São Paulo Zoo Park is highly diverse and its structure varies throughout the process. Furthermore, it was also observed that over 30% of metgenomic sequences derived from bacteria obtained with unknown genomes, suggesting a potential for discovering new thermostable enzymes. For this reason, the focus of this work is the prospection and the characterization of enzymes responsible for the degradation of biomass in the microbiomes from São Paulo Zoo, mainly lipases, xylanases and pectinases. Metagenomic and metatranscriptomic approaches will be used for screening genes encoding enzymes of biotechnological interest. Afterwards, will be performed recombinant expression and biochemical characterization of the enzymes involved in the biomass degradation during the composting process. At the end, we intend to expand the scale of recombinant enzymes expression that presenting satisfactory characteristics. The project has a second outlook, which aims to evaluate the production of lipases, pectinases and xylanases in cultivable consortia of thermophilic bacteria obtained from composting samples. Lastly, we will carry out the bacteria consortia cultivation in defined media enriched with the target substrates of these enzymes. Thereafter, taxonomic composition of the consortia will be investigated by rRNA16S sequencing. It is noteworthy that the protocols involved in the metagenomic and the metatranscriptomic approaches are standardized, being successfully applied to the thematic project coordinated by João C. Setubal and Aline M. da Silva.