Microbial ecology of full-scale wastewater treatment systems in the Polar Arctic Circle: Archaea, Bacteria and Fungi

Abstract

Seven full-scale biological wastewater treatment systems located in the Polar Arctic Circle region in Finland were investigated to determine their Archaea, Bacteria and Fungi community structure, and their relationship with the operational conditions of the bioreactors by the means of quantitative PCR, massive parallel sequencing and multivariate redundancy analysis. The results showed dominance of Archaea and Bacteria members in the bioreactors. The activated sludge systems showed strong selection of Bacteria but not for Archaea and Fungi, as suggested by diversity analyses. Core OTUs in influent and bioreactors were classified as Methanobrevibacter, Methanosarcina, Terrestrial Group Thaumarchaeota and unclassified Euryarchaeota member for Archaea; Trichococcus, Leptotrichiaceae and Comamonadaceae family, and Methylorosula for Bacteria and Trichosporonaceae family for Fungi. All influents shared core OTUs in all domains, but in bioreactors this did not occur for Bacteria. Oligotype structure of core OTUs showed several ubiquitous Fungi oligotypes as dominant in sewage and bioreactors. Multivariate redundancy analyses showed that the majority of core OTUs were related to organic matter and nutrients removal. Also, there was evidence of competition among Archaea and Fungi core OTUs, while all Bacteria OTUs were positively correlated among them. The results obtained highlighted interesting features of extremely cold temperature bioreactors.

Metagenomics Study of the Microbes in Constructed Wetland System Treating Sewage

“…Incertae sedis is indicated as one of the core microbial population existing in WWTP located at different geographic locations and its role in biological WWTP is not well explained. Tremellomycetes is reported to be present in flocular and granular sludge, it is unculturable and dominant in polar arctic circle bioreactors [32]. Agaricomycetes class is capable of degrading pharmaceutical active compounds and bioremediation of crude oil contaminated site [33].…”

“…At family level, Trichosporonaceae predominates. Trichosporon in Trichosporonaceae family dominated in fungi domain in bioreactor playing an important role in denitrification and Oxidation of ammonia [32]. The family Nectriaceae has a cosmopolitan distribution and enriched upon organic amendments in wheat field, indicating its potential to degrade organics.…”

Induction of microbial oxidative stress as a new strategy to enhance the enzymatic degradation of organic micropollutants in wastewater

“…Genomic analysis has revealed that many common wastewater microorganisms have considerable potential to produce specialised enzymes and metabolites with OMP degradation potential (31–34). The core bacterial families observed in our study from the phylum Proteobacteria have been reported as organic micropollutant degraders in WWTPs treating pharmaceutical, petroleum refinery, domestic and agricultural wastewater (24). Commamonadaceae represented ~40% of the bacteria in both perturbed (0.25 cycles/hr, high-DO) and non-perturbed constant high-DO aeration regimes, followed by Rhodocyclaceae and Syntropahceae (15%) in 0.16 cycles/hr, low-DO perturbed conditions.…”

“…A total of 527 operational taxonomic units (97% OTUs) were identified in the cultures, of which 513 represented Bacteria and 13 were Archaea. The percentage occurrence of bacteria belonging to the phylum Proteobacteria, which are linked to the biotransformation of recalcitrant contaminants in wastewaters (24), predominates and correlated with respect to ecological variables like process operations (changing oxygen conditions), influent wastewater characteristics or geographical location (25). Comamonadaceae (40%) was the dominant family in cultures perturbed with 0.25 cycles/hr in high-DO regime while a higher abundance of Methylophilaceae (25%) was found in 1 and 2 cycles/hr treated cultures at high-DO range (Figure S2 in the supplementary information).…”

Insight on the bacterial ecology in membrane bioreactor: Operational conditions effect over dominant ecological players

“…First, a Shannon entropy calculation was computed over the alignment of all contigs within the OTU of interest. The results of the Shannon entropy analysis were subsequently taken to configure the oligotype distribution attending to a number of high‐entropy nodes, starting with the highest entropy node and adding the following in order one‐by‐one until the purity score of the oligotypes distribution was equal or higher than 0.90 . For construction of the oligotype distribution and removal of noise, the minimum substantive abundance was taken as 200.…”