| Congresso Brasileiro de Microbiologia 2023 | Resumo: 995-1 | ||||
Resumo:In the Santos Basin, there is a field of pockmarks characterized by the presence of numerous saline diapirs. Surface layers of sediments from three stations in this area were collected using a stainless-steel box corer. The shotgun metagenomic sequencing of the samples was performed on the Illumina Hiseq platform. Genome reconstruction was performed using Anvi'o software and taxonomic classification using the Genome Taxonomy Database Toolkit. For more detailed analyzes, we selected MAG_00001 which obtained the highest quality scores (94.2% completeness and 2.1% contamination). The sequence of the 16S rRNA gene extracted from MAG_00001 was classified through the SILVA database v.138. Initially, MAG_00001 was classified as belonging to the Methylomirabilales order and the CSP1-5 family, a non-methanotrophic methylotroph. However, the sequence of the 16S rRNA gene was also classified as Methylomirabilales order, but belonging to the Methylomirabilaceae family, known to be methanotrophic. To resolve this issue, a pangenome was performed using genomes of methanotrophic organisms available at NCBI, such as Candidatus Methylomirabilis oxyfera (Ca. M. oxyfera), Candidatus Methylomirabilis limnetica (Ca. M. limnetica), in addition to the non-methanotrophic genome CSP1-5. The DRAM tool was also used for gene annotation. A total of 6.174 gene clusters have been identified across the pangenome. MAG_00001 was more similar to CSP1-5 (76.7% ANI) compared to Ca. M. oxyfera (70.3% ANI) and Ca. M. limnetica (70.5% ANI). We observed that in the central cluster of the pangenome, MAG_00001 also contained lanthanide-dependent Xox-type methanol dehydrogenase, as did the other genomes. The genome of MAG_00001 and CSP1-5 did not show any gene associated with methane oxidation (pmoABC) or the operon nirS (Nitrite reductase) or norBC (Nitric oxide reductase). The nxrAB gene, involved in nitrite oxidation, was present in MAG MAG_00001 and in the CSP1-5 genome but was not present in methanotrophs. Therefore, based on these analyses, it was concluded that MAG_00001 belongs to the CSP1-5 family. These results highlight that studies based only on amplicon sequencing can lead to the misclassification of members of Methylomirabilales since the order contains both methanotrophic and non-methanotrophic members. As a result, the relevance of methanol metabolism may have been overlooked in previous studies. Palavras-chave: CSP1-5, Salt Diapirs, Methylotroph, Metagenome, Atlantic Ocean Agência de fomento:Fundação de amparo à pesquisa do estado de São Paulo (FAPESP); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) | |||||