Banca de QUALIFICAÇÃO: BIANCA CRISTIANE FERREIRA SANTIAGO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : BIANCA CRISTIANE FERREIRA SANTIAGO
DATE: 31/01/2022
TIME: 10:00
LOCAL: meet.google.com/pax-kuia-bvz
TITLE:

Metagenomic analysis of marine samples from tropical and subtropical regions

KEY WORDS:

Functional Annotation. Biodiversity. Taxonomic Classification. Metagenomics. Tara
Oceans.

PAGES: 60
BIG AREA: Ciências Biológicas
AREA: Biologia Geral
SUMMARY:

About 71% of the Earth's surface ecosystem is covered by ocean, responsible for containing 97% of all the Earth's water, with plankton being its dominant life form. Microorganisms play an essential role in maintaining the planet's system, since they are sources of energy and nutrients for living beings, realize almost half of net primary production, maintain chemical balance in the atmosphere and export photosynthetically fixed carbon to the deepest layers of the ocean. Ocean ecosystem biology studies how biotic and abiotic factors determine ocean ecosystem properties. With the emergence of global-scale studies of open ocean organisms, much has been discovered about the genomics of oceanic microbial communities. One of the main projects in this category today is Tara Oceans, a multidisciplinary project aiming to understand the diversity, interactions, functions and phenotypic complexity at taxonomic and spatial scales of plankton, through about 35000 samples with millions of organisms collected at depths of up to 2000 m in 210 stations across the oceans. The main objective of this work was to compare oceanic samples exploring the abundance, diversity, and function of microorganisms found at similar latitudes with species present in the Brazilian coast, in order to understand how abiotic factors affect the biodiversity of these species. For this, the samples were selected according to the stations that followed a latitude filter (5º above station 76 and 5º below station 78) and layer filter, in which only stations that had samples in the three layers (SRF, DCM and MES) simultaneously were considered. This filtering resulted in 8 stations with a sum of 76 samples. These data were processed through a modular protocol, following the standard flow of a metagenomics analysis: pre-processing, sequence alignment with a reference protein bank, taxonomic classification and functional annotation. With the results obtained from this process, it was possible to compare the abundance and diversity of these samples and to note and analyze the results of this comparison. A greater diversity of organisms was observed in the deepest layer (MES) and there was no significant difference in abundance between the explored depth layers. Analogous to this, the shallower layer (SRF) presents organisms with very close functional annotation, among the biological process functions, the most frequent terms are respectively “DNA replication”, “translation” and “transmembrane transport”; very similar, the second layer (DCM) has the most present functions among its organisms: “translation”, “DNA replication” and “transmembrane transport”; on the other hand, the deepest layer (MES) has as main functions “transmembrane transport”, “methylation” and “translation”. Despite the subtle intra-layer differences, the deepest layer stands out from the others in terms of the diversity and function of microorganisms. Likewise, no significant distinction of abundance, diversity or function was observed comparing exclusively samples from collection stations in different geographic points.

BANKING MEMBERS:
Presidente - 1507794 - RODRIGO JULIANI SIQUEIRA DALMOLIN
Interno - 2276280 - CESAR RENNO COSTA