Characterization of Microbial Communities in Wastewater Treatment Plants Containing Heavy Metals Located in Chemical Industrial Zones

Abstract

Water pollution caused by heavy metals (HMs) poses a serious risk to human health and the environment and can increase the risk of diabetes, cancer, and hypertension in particular. In this study, two full-scale wastewater treatment plants (WWTPs) in industrial zones in southern China were selected to analyze the microbial community structure, diversity, similarity, and differentiation in the anoxic/oxic (AO) and anoxic/oxic membrane bioreactor (AO-MBR) units under the stress of HMs. High-throughput sequencing showed that microbial diversity and abundance were higher in the AO process than in the AO-MBR process. In the two WWTPs, the common dominant phyla were Proteobacteria and Bacteroidetes, while the common dominant genera were Gemmatimonadaceae, Anaerolineaceae, Saprospiraceae, and Terrimonas. Manganese (Mn) and zinc (Zn) positively correlated with Saccharimonadales, Nakamurella, Micrococcales, and Microtrichales, whereas copper (Cu) and iron (Fe) positively correlated with Longilinea and Ferruginibacter. Additionally, the relative abundances of Chloroflexi, Patescibacteria, and Firmicutes differed significantly (p < 0.05) between the two processes. These results may provide comprehensive outlooks on the characterization of microbial communities in WWTPs, which could also help to reduce the potential environmental risks of the effluent from WWTPs located in industrial zones.

Large-Scale Integration of Amplicon Data Reveals Massive Diversity within Saprospirales, Mostly Originating from Saline Environments

“…Saprospirales can indeed be found in various environments, such as saline water, freshwater, soil, bioreactors, and wastewater treatment plants, as has been already mentioned in various studies [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 ]. In addition, air, plants, as well as terrestrial and saline water hosts are also potential environments for Saprospirales.…”

“…Bacteria belonging to Saprospirales can be found in natural ecosystems such as marine and freshwater environments, and soils [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ]. Furthermore, several studies have reported that Saprospirales members can be found in wastewater treatment plants, and especially in activated sludge and anaerobic ammonium oxidation reactors [ 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 ]. Regarding the latter, hydrolysis of proteins, denitrification, aromatic compound degradation, and organic matter decomposition are confirmed capabilities of certain bacteria belonging to the order Saprospirales [ 30 , 32 , 33 , 34 , 35 , 36 , 37 ].…”

Exploring Community and Kinetic Shifts in Nitrifying Microbial Communities in Low Dissolved Oxygen Activated Sludge Facilities for Energy-Efficient Biological Nitrogen Removal

“…Additionally, it is noteworthy that there were heterotrophic microorganisms present in the biomass that are involved in the nitrogen cycle. For example, Haliangium and Comamonas (2.4 and 2.5% of the total reads in TCMCRWS, respectively) are aerobic heterotrophic capable of NO 2 – reduction, , while members of the family Gemmataceae (1.25% of the total reads in TCMCRWS) can be N 2 O-reducing organisms …”

“…For example, Haliangium and Comamonas (2.4 and 2.5% of the total reads in TCMCRWS, respectively) are aerobic heterotrophic capable of NO 2 − reduction, 52,53 while members of the family Gemmataceae (1.25% of the total reads in TCMCRWS) can be N 2 O-reducing organisms. 54 The sum of the relative abundances of the putative AOB (Nitrosomonas and Nitrosospira, etc.) and NOB taxa (Nitrospira and Nitrotoga) were estimated from the microbial composition profiles (Figure 3a,b).…”

The diversity of indigenous and potential bacteria as bioremediator of palm oil mill secondary effluent (POMSE) by metagenomics assessment

“…Other than organic wastes, Proteobacteria and Bacteroidetes were also found in wastewaters with high heavy metals. The most abundant phyla in wastewater treatment plants containing heavy metals located in chemical industrial zones for all the samples are Proteobacteria, Chloroflexi, Actinobacteriota, Bacteroidetes, and Planctomycetes, in the order of their relative proportions (Zeng et al 2022). Proteobacteria, Bacteroidota, Patescibacteria, and Chloroflexi were the dominant phyla from active sludge in China's tropical municipal wastewater treatment plant (Gu et al 2022).…”