Planktonic microbial profiling in water samples from a Brazilian Amazonian reservoir

Abstract

Our comprehension of the dynamics and diversity of freshwater planktonic bacterial communities is far from complete concerning the Brazilian Amazonian region. Therefore, reference studies are urgently needed. We mapped bacterial communities present in the planktonic communities of a freshwater artificial reservoir located in the western Amazonian basin. Two samples were obtained from rainy and dry seasons, the periods during which water quality and plankton diversity undergo the most significant changes. Hypervariable 16S rRNA and shotgun sequencing were performed to describe the first reference of a microbial community in an Amazonian lentic system. Microbial composition consisted mainly of Betaproteobacteria, Cyanobacteria, Alphaproteobacteria, and Actinobacteria in the dry period. The bacteria distribution in the rainy period was notably absent of Cyanobacteria. Microcystis was observed in the dry period in which the gene cluster for cyanotoxins was found. Iron acquisition gene group was higher in the sample from the rainy season. This work mapped the first inventory of the planktonic microbial community of a large water reservoir in the Amazon, providing a reference for future functional studies and determining other communities and how they interact.

Comparison of bacterial communities from the surface and adjacent bottom layers water of Billings reservoir

“…Taxonomical composition revealed that the Proteobacteria phyla were most common, followed by Cyanobacteria and Actinobacteria. These results are consistent with other Brazilian studies that describe the microbial communities in the Amazon basin (22)(23)(24) and Tocantins River (25) but somewhat different from those previously described for reservoirs in China. For instance, Qu J et al used the 16S rDNA Illumina approach and showed that Firmicutes, Proteobacteria, Cyanobacteria, and Bacteroidetes were the dominant bacterial phyla in the Miyun Reservoir, which is considered the largest man-made reservoir in North China.…”

Comparison of Bacterial Communities from the Surface and Adjacent Bottom Layers Water of Billings Reservoir

“…Taxonomical composition revealed that the Proteobacteria phyla were most common, followed by Cyanobacteria and Actinobacteria. These results are consistent with other Brazilian studies that describe the microbial communities in the Amazon basin [22][23][24] and Tocantins River [25] but somewhat different from those previously described for reservoirs in China. For instance, Qu J et al used the 16S rDNA Illumina approach and showed that Firmicutes, Proteobacteria, Cyanobacteria, and Bacteroidetes were the dominant bacterial phyla in the Miyun Reservoir, which is considered the largest man-made reservoir in North China.…”

Characterization of Bacterial Communities from the Surface and Adjacent Bottom Layers of Water in the Billings Reservoir

“…The taxonomical composition revealed that the Cyanobacteria phylum was the most abundant in the community, followed by Proteobacteria and Actinobacteria . These results are consistent with other Brazilian studies that describe bacterial communities in the Amazon basin [ 57 , 58 , 59 ] and Tocantins River [ 60 ], but are somewhat different from those previously described for reservoirs in China. For instance, Qu J et al [ 56 ] used the 16S rDNA Illumina approach to show that Firmicutes , Proteobacteria , Cyanobacteria , and Bacteroidetes were the dominant bacterial phyla in the Miyun Reservoir, which is considered the largest man-made reservoir in North China.…”