Banca de DEFESA: CÍNTIA CAROLINE GOUVEIA DA SILVA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : CÍNTIA CAROLINE GOUVEIA DA SILVA
DATE: 14/04/2023
TIME: 14:00
LOCAL: Prédio Prof. Mateus Rosas Ribeiro
TITLE:

Microbiome of Amazonian Dark Earth: potential for discovering new bioproducts

KEY WORDS:

Anthropogenic Soils. Microbial Ecology. Prospection. Sequencing.

PAGES: 153
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SUMMARY:

Amazonian Dark Earth (ADE) are anthropogenic origin soils with high fertility and organic matter content differently of soils of those region, and this soil may increase the microbial communities. Our study aimed to reveal the microbial diversity, metabolic processes and biogeochemical transformations related to the maintenance of fertility and sustainability of ADE and its biotechnological potential through molecular and culture-dependent techniques. Soil samples was collected in the Eastern Amazon and packed in bags for physical, chemical, and microbiological analyses. Prospection of bacteria from the ADE profile was performed using the serial dilution method and, subsequently, the isolates were tested in vitro to produce Indole Acetic Acid (IAA), siderophores, phosphate solubilization and biological nitrogen fixation (BNF). Based on the results of phosphate solubilization, AIA and siderophores production, we selected 52 isolates for DNA extraction, nifH and acdS gene amplification and 16S rRNA gene sequencing. In addition, total soil DNA was extracted, quantified, and had its metagenome sequenced. The means of the mechanisms were submitted to the Skott Knott test at 5% probability, using the SISVAR program version 5.1. About bioinformatics analyses, the open access platform KBase was used, where taxonomic and metabolic notes about the inserted sequences were observed. ADE soil was classified as dystrophic Gleissolo A-Cg with acidic pH both in the ADE profile and in the adjacent soil (ADJ), besides there was nutrient increase in depth, low base saturation and high aluminum saturation.These soils have a predominance of sand and clay fractions, and the Glomalin showed higher levels in the A horizon. Considering 466 ADE soil isolates, 84 of them solubilized phosphate, 113 produced AIA and 13 produced siderophores. About 149 isolates selected for BFN, only 3 were negative and the presence of nifH and acdS genes of the 52 isolates, 23 and 12 were positive, respectively. The sequencing of the 16S rRNA gene revealed the predominance of the Bacillus and Pseudomonas genera. Furthermore, metagenomics revealed Acidobacteria, Proteobacteria, Chloroflexi and Actinobacteria as the dominant phyla in ADE and ADJ samples. About the classes, Actinobacteria, Alphaproteobacteria Deltaproteobacteria and Betaproteobacteria, they were the most present and the orders Rhizobiales, Acidobacteriales, Ktedonobacterales, Streptomycetales and Burkholderiales were highlighted in all samples. A great diversity of families was observed, highlighting Acidobacteriaceae, Streptomycetaceae, Solibacteriaceae and Bradyrhizobiaceae. The predominant genera and species were Streptomyces, Bradyrhizobium, Candidatus Sulfopaludibacter and Candidatus Sulfotelmatobacter; Acidobacteria bacterium, Chloroflexi bacterium, Candidatus Bathyarchaeota archeon, Terrabacteria group bacterium ANGP1, Actinobacteria bacterium, Alphaproteobacteria bacterium, Gammaproteobacteria bacterium, and Planctomycetes bacterium, respectively. Considering the metabolic and functional soil samples profile, there were evidence of proteins and enzymes related to glycolysis, pentose, Krebs cycle, electron transport chain, carbohydrate cycle, N, S, methane, arsenic, and mercury cycle. Overall, this study found a high potential of the microorganisms of ADE and its ability to perform important ecological functions, guaranteeing the proper functioning of the ecosystem.

COMMITTEE MEMBERS:
Externo à Instituição - ADRIANO REIS LUCHETA
Externo à Instituição - ARTHUR PRUDÊNCIO DE ARAÚJO PEREIRA - UFC
Interna - ERIKA VALENTE DE MEDEIROS
Externo à Instituição - FELIPE MARTINS DO RÊGO BARROS - USP
Presidente - GISELLE GOMES MONTEIRO FRACETTO