Bacterial diversity in deep-sea sediments under influence of asphalt seep at the São Paulo Plateau

Abstract

Here we investigated the diversity of bacterial communities from deep-sea surface sediments under influence of asphalt seeps at the Sao Paulo Plateau using next-generation sequencing (NGS) method.Sampling was performed at North São Paulo Plateau using the human occupied vehicle Shinkai 6500 and her support vessel Yokosuka. The microbial diversity was studied at two surficial sediment layers (0-1 and 1-4 cm) of five samples collected in cores in water depths ranging from 2,456-2,728 m. Bacterial communities were studied through sequencing of 16S rRNA gene on the Ion Torrent platform and clustered in operational taxonomic units. We observed high diversity of bacterial sediment communities as previously described by other studies. When we considered community composition, the most abundant classes were Alphaprotebacteria (27.7%), Acidimicrobiia (20%), Gammaproteobacteria (11.3%) and Deltaproteobacteria (6.6%). Most abundant OTUs at family level were from two uncultured bacteria from Actinomarinales (5.95%) and Kiloniellaceae (3.17%). The unexpected high abundance of Alphaproteobacteria and Acidimicrobiia in our deep-sea microbial communities may be related to the presence of asphalt seep at North São Paulo Plateau, since these bacterial classes contain bacteria that possess the capability of metabolizing hydrocarbon compounds.

Spatial patterns of microbial diversity in Fe-Mn deposits and associated sediments in the Atlantic and Pacific oceans

“…Unexpectedly, SAR11 clade was detected only in the RGR seamount. Closely related sequences of SAR11 were reported previously in sediments across the São Paulo Plateau (Queiroz et al, 2020) and crusts from RGR (Bergo et al, 2021). SAR11 includes carbon-oxidizing bacteria with multiple depth-specific ecotypes ((Cameron Thrash et al, 2014;Giovannoni, 2017)).…”

Switch of Bacteria Community Under Oxygen Depletion in Sediment of Bohai Sea

“…Most of the sequences assigned to phylum Actinobacteria belonged to class Acidimicrobiia, and two most representative OTUs were classified as uncultured Actinobacterium (previously classified as OM1 clade), an eosinophilic family (Goodfellow et al, 2012;Chen et al, 2016). This group of bacteria was usually abundant in high salinity and pH sediments, and related to the capability of metabolizing hydrocarbon compounds (Queiroz et al, 2020). Their great abundance in the studied sites might contribute to the degradation of severe oil pollution in the coast of Bohai Sea (Liu et al, 2016;Yu et al, 2018).…”

Actinobacteria from Arctic and Atlantic deep-sea sediments—Biodiversity and bioactive potential

“…For instance, most of the dominance of the Actinobacteria phylum in the Arctic deep-sea samples was driven by the predominance of Actinomarinales , Ilumatobacteraceae , and Microtrichaceae , which represented on average 97% of the Actinobacteria phylum, while in the Azores and Madeira deep-sea sediments it was noted a higher diversity of actinobacterial taxa (including the dominance of Actinomarinales ), despite their lower overall relative abundances in the prokaryotic microbiomes of these sediments. Still, the high prevalence of Actinomarinales in the deep-sea sediments across the different regions studied is likely correlated with the cosmopolitan distribution of this taxon across the marine environment ( Ghai et al, 2013 ), having also been observed in deep-sea sediments from São Paulo Plateau, in the Atlantic Ocean ( Queiroz et al, 2020 ). Yet, this abundance-diversity dichotomy is less expressive at the genus level, probably due to a low resolution of taxonomic classifications achieved in this study.…”