Bioaerosols Play a Major Role in the Nasopharyngeal Microbiota Content in Agricultural Environment

Background: Bioaerosols are a major concern for public health and sampling for exposure assessment purposes is challenging. The nasopharyngeal region could be a potent carrier of long-term bioaerosol exposure agents. This study aimed to evaluate the correlation between nasopharyngeal bacterial flora of swine workers and the swine barns bioaerosol biodiversity. Methods: Air samples from eight swine barns as well as nasopharyngeal swabs from pig workers (n = 25) and from a non-exposed control group (n = 29) were sequenced using 16S rRNA gene high-throughput sequencing. Wastewater treatment plants were used as the industrial, low-dust, non-agricultural environment control to validate the microbial link between the bioaerosol content (air) and the nasopharynxes of workers. Results: A multivariate analysis showed air samples and nasopharyngeal flora of pig workers cluster together, compared to the non-exposed control group. The significance was confirmed with the PERMANOVA statistical test (p-value of 0.0001). Unlike the farm environment, nasopharynx samples from wastewater workers did not cluster with air samples from wastewater treatment plants. The difference in the microbial community of nasopharynx of swine workers and a control group suggest that swine workers are carriers of germs found in bioaerosols. Conclusion: Nasopharynx sampling and microbiota could be used as a proxy of air sampling for exposure assessment studies or for the determination of exposure markers in highly contaminated agricultural environments.

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The capacity of wastewater treatment plants drives bacterial community structure and its assembly

Scientific Reports ◽

10.1038/s41598-019-50952-0 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Young Kyung Kim ◽

Keunje Yoo ◽

Min Sung Kim ◽

Il Han ◽

Minjoo Lee ◽

...

Keyword(s):

Wastewater Treatment ◽

Community Structure ◽

Bacterial Community ◽

Activated Sludge ◽

Community Assembly ◽

Bacterial Communities ◽

Wastewater Treatment Plants ◽

High Capacity ◽

Operating Conditions ◽

Rrna Gene

Abstract Bacterial communities in wastewater treatment plants (WWTPs) affect plant functionality through their role in the removal of pollutants from wastewater. Bacterial communities vary extensively based on plant operating conditions and influent characteristics. The capacity of WWTPs can also affect the bacterial community via variations in the organic or nutrient composition of the influent. Despite the importance considering capacity, the characteristics that control bacterial community assembly are largely unknown. In this study, we discovered that bacterial communities in WWTPs in Korea and Vietnam, which differ remarkably in capacity, exhibit unique structures and interactions that are governed mainly by the capacity of WWTPs. Bacterial communities were analysed using 16S rRNA gene sequencing and exhibited clear differences between the two regions, with these differences being most pronounced in activated sludge. We found that capacity contributed the most to bacterial interactions and community structure, whereas other factors had less impact. Co-occurrence network analysis showed that microorganisms from high-capacity WWTPs are more interrelated than those from low-capacity WWTPs, which corresponds to the tighter clustering of bacterial communities in Korea. These results will contribute to the understanding of bacterial community assembly in activated sludge processing.

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“Candidatus Dechloromonas phosphoritropha” and “Ca. D. phosphorivorans”, novel polyphosphate accumulating organisms abundant in wastewater treatment systems

The ISME Journal ◽

10.1038/s41396-021-01029-2 ◽

2021 ◽

Author(s):

Francesca Petriglieri ◽

Caitlin Singleton ◽

Miriam Peces ◽

Jette F. Petersen ◽

Marta Nierychlo ◽

...

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plants ◽

Niche Partitioning ◽

16S Rrna Gene Sequencing ◽

Abundant Species ◽

Phosphate Removal ◽

Rrna Gene ◽

Biological Phosphorus Removal ◽

Polyphosphate Accumulating Organisms

AbstractMembers of the genus Dechloromonas are often abundant in enhanced biological phosphorus removal (EBPR) systems and are recognized putative polyphosphate accumulating organisms (PAOs), but their role in phosphate removal is still unclear. Here, we used 16S rRNA gene sequencing and fluorescence in situ hybridization (FISH) to investigate the abundance and distribution of Dechloromonas spp. in Danish and global wastewater treatment plants. The two most abundant species worldwide revealed in situ dynamics of important intracellular storage polymers, measured by FISH-Raman in activated sludge from four full-scale EBPR plants and from a lab-scale reactor fed with different substrates. Moreover, seven distinct Dechloromonas species were determined from a set of ten high-quality metagenome-assembled genomes (MAGs) from Danish EBPR plants, each encoding the potential for polyphosphate (poly-P), glycogen, and polyhydroxyalkanoates (PHA) accumulation. The two species exhibited an in situ phenotype in complete accordance with the metabolic information retrieved by the MAGs, with dynamic levels of poly-P, glycogen, and PHA during feast-famine anaerobic–aerobic cycling, legitimately placing these microorganisms among the important PAOs. They are potentially involved in denitrification showing niche partitioning within the genus and with other important PAOs. As no isolates are available for the two species, we propose the names Candidatus Dechloromonas phosphoritropha and Candidatus Dechloromonas phosphorivorans.

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In Situ Characterization ofNitrospira-Like Nitrite-Oxidizing Bacteria Active in Wastewater Treatment Plants

Applied and Environmental Microbiology ◽

10.1128/aem.67.11.5273-5284.2001 ◽

2001 ◽

Vol 67 (11) ◽

pp. 5273-5284 ◽

Cited By ~ 513

Author(s):

Holger Daims ◽

Jeppe L. Nielsen ◽

Per H. Nielsen ◽

Karl-Heinz Schleifer ◽

Michael Wagner

Keyword(s):

Wastewater Treatment ◽

16S Rrna ◽

Laser Scanning ◽

Wastewater Treatment Plants ◽

Carbon Sources ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Rrna Gene ◽

Phylogenetic Affiliation

ABSTRACT Uncultivated Nitrospira-like bacteria in different biofilm and activated-sludge samples were investigated by cultivation-independent molecular approaches. Initially, the phylogenetic affiliation of Nitrospira-like bacteria in a nitrifying biofilm was determined by 16S rRNA gene sequence analysis. Subsequently, a phylogenetic consensus tree of theNitrospira phylum including all publicly available sequences was constructed. This analysis revealed that the genusNitrospira consists of at least four distinct sublineages. Based on these data, two 16S rRNA-directed oligonucleotide probes specific for the phylum and genus Nitrospira, respectively, were developed and evaluated for suitability for fluorescence in situ hybridization (FISH). The probes were used to investigate the in situ architecture of cell aggregates ofNitrospira-like nitrite oxidizers in wastewater treatment plants by FISH, confocal laser scanning microscopy, and computer-aided three-dimensional visualization. Cavities and a network of cell-free channels inside the Nitrospiramicrocolonies were detected that were water permeable, as demonstrated by fluorescein staining. The uptake of different carbon sources byNitrospira-like bacteria within their natural habitat under different incubation conditions was studied by combined FISH and microautoradiography. Under aerobic conditions, theNitrospira-like bacteria in bioreactor samples took up inorganic carbon (as HCO3 − or as CO2) and pyruvate but not acetate, butyrate, and propionate, suggesting that these bacteria can grow mixotrophically in the presence of pyruvate. In contrast, no uptake by theNitrospira-like bacteria of any of the carbon sources tested was observed under anoxic or anaerobic conditions.

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Bacteria from the Genus Arcobacter Are Abundant in Effluent from Wastewater Treatment Plants

Applied and Environmental Microbiology ◽

10.1128/aem.03044-19 ◽

2020 ◽

Vol 86 (9) ◽

Cited By ~ 5

Author(s):

Jannie Munk Kristensen ◽

Marta Nierychlo ◽

Mads Albertsen ◽

Per Halkjær Nielsen

Keyword(s):

Wastewater Treatment ◽

Pathogenic Bacteria ◽

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Amplicon Sequencing ◽

Rrna Gene ◽

Content Type ◽

Effluent Quality ◽

Culture Independent ◽

Influent Wastewater

ABSTRACT Pathogenic bacteria in wastewater are generally considered to be efficiently removed in biological wastewater treatment plants. This understanding is almost solely based on culture-based control measures, and here we show, by applying culture-independent methods, that the removal of species in the genus Arcobacter was less effective than for many other abundant genera in the influent wastewater. Arcobacter was one of the most abundant genera in influent wastewater at 14 municipal wastewater treatment plants and was also abundant in the “clean” effluent from all the plants, reaching up to 30% of all bacteria as analyzed by 16S rRNA gene amplicon sequencing. Metagenomic analyses, culturing, genome sequencing of Arcobacter isolates, and visualization by fluorescent in situ hybridization (FISH) confirmed the presence of the human-pathogenic Arcobacter cryaerophilus and A. butzleri in both influent and effluent. The main reason for the high relative abundance in the effluent was probably that Arcobacter cells, compared to those of other abundant genera in the influent, did not flocculate and attach well to the activated sludge flocs, leaving a relatively large fraction dispersed in the water phase. The study shows there is an urgent need for new standardized culture-independent measurements of pathogens in effluent wastewaters, e.g., amplicon sequencing, and an investigation of the problem on a global scale to quantify the risk for humans and livestock. IMPORTANCE The genus Arcobacter was unexpectedly abundant in the effluent from 14 Danish wastewater treatment plants treating municipal wastewater, and the species included the human-pathogenic A. cryaerophilus and A. butzleri. Recent studies have shown that Arcobacter is common in wastewater worldwide, so the study indicates that discharge of members of the genus Arcobacter may be a global problem, and further studies are needed to quantify the risk and potentially minimize the discharge. The study also shows that culture-based analyses are insufficient for proper effluent quality control, and new standardized culture-independent measurements of effluent quality encompassing most pathogens should be considered.

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Drug resistance in airborne bacteria isolated from waste management and wastewater treatment plants in Olsztyn

E3S Web of Conferences ◽

10.1051/e3sconf/201910000066 ◽

2019 ◽

Vol 100 ◽

pp. 00066 ◽

Cited By ~ 2

Author(s):

Jacek Potorski ◽

Izabela Koniuszewska ◽

Małgorzata Czatzkowska ◽

Monika Harnisz

Keyword(s):

Antibiotic Resistance ◽

Wastewater Treatment ◽

Waste Management ◽

Wastewater Treatment Plants ◽

Antibiotic Resistance Genes ◽

Resistant Bacteria ◽

Bacterial Strains ◽

Bacterial Counts ◽

Air Samples ◽

Processing Line

Wastewater treatment plants (WWTPs) and municipal waste management plants (MWMPs) emit bioaerosols containing potentially pathogenic biological components which post a threat for human health. Microbiological monitoring supports evaluations of the antibiotic resistance (AR) of airborne microorganisms and the relevant health risks. The aim of this study was to analyze the microbiological quality of air sampled in a WWTP and MWMP in Olsztyn based on total bacterial counts, the presence of bacteria resistant to three antibiotic classes (beta-lactams, tetracyclines and chloramphenicol) and genes encoding resistance to these antibiotics (blaTEM, blaSHV, blaCMY-2, blaAmpC, tet(M), tet(A), tet(X), tet(B), cmlA, floR, fexA, fexB and catA1 ). Bacterial counts were higher in air samples collected from the MWMP (~104 CFU/m3) than from the WWTP (101–103 CFU/m3). A similar trend was noted in the counts of antibiotic resistant bacteria (ARB). The abundance of ARB did not exceed 1.7 x 102 CFU/m3 in WWTP samples, but was higher at up to 4.2 x 103 CFU/m3 in MWMP samples. Bacteria resistant to doxycycline were least prevalent in the analyzed ARB. In the group of 49 tested bacterial strains, 44 harbored at least one of the analyzed antibiotic resistance genes (ARGs). A comparison of ARGs in all bacterial strains isolated from WWTP and MWMP air samples revealed the highest diversity and prevalence of ARGs in the samples collected in the mechanical segment of the waste processing line in MWMP and the biological segment of the wastewater processing line in WWTP. The results of this study point to high microbiological contamination of air in MWMPs and WWTPs which are reservoirs of ARB and ARGs and potential sources of AR.

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Probabilistic exposure assessment of DEEDMAC using measured effluent and sludge concentrations from 41 wastewater treatment plants across the United States

The Science of The Total Environment ◽

10.1016/j.scitotenv.2019.05.342 ◽

2019 ◽

Vol 684 ◽

pp. 247-253 ◽

Cited By ~ 2

Author(s):

Jennifer Menzies ◽

Kenneth Casteel ◽

Kenneth Wehmeyer ◽

Monica Lam ◽

Kathleen McDonough

Keyword(s):

United States ◽

Wastewater Treatment ◽

Exposure Assessment ◽

Wastewater Treatment Plants ◽

The United States ◽

Probabilistic Exposure Assessment

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Antimicrobial resistance gene surveillance in the receiving waters of an upgraded wastewater treatment plant

FACETS ◽

10.1139/facets-2017-0085 ◽

2018 ◽

Vol 3 (1) ◽

pp. 128-138 ◽

Cited By ~ 5

Author(s):

Claire N. Freeman ◽

Lena Scriver ◽

Kara D. Neudorf ◽

Lisbeth Truelstrup Hansen ◽

Rob C. Jamieson ◽

...

Keyword(s):

Wastewater Treatment ◽

Antimicrobial Resistance ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Nutrient Content ◽

Rrna Gene ◽

Treated Effluent ◽

Antimicrobial Resistance Genes ◽

Antimicrobial Resistance Gene ◽

The Impact

Wastewater treatment plants (WWTPs) have been identified as hotspots for antimicrobial resistance genes (ARGs) and thus represent a critical point where patterns in ARG abundances can be monitored prior to their release into the environment. The aim of the current study was to measure the impact of the release of the final treated effluent (FE) on the abundance of ARGs in the receiving water of a recently upgraded WWTP in the Canadian prairies. Sample nutrient content (phosphorous and nitrogen species) was measured as a proxy for WWTP functional performance, and quantitative PCR (qPCR) was used to measure the abundance of eight ARGs, the intI1 gene associated with class I integrons, and the 16S rRNA gene. The genes ermB, sul1, intI1, blaCTX-M, qnrS, and tetO all had higher abundances downstream of the WWTP, consistent with the genes with highest abundance in the FE. These findings are consistent with the increasing evidence suggesting that human activity affects the abundances of ARGs in the environment. Although the degree of risk associated with releasing ARGs into the environment is still unclear, understanding the environmental dimension of this threat will help develop informed management policies to reduce the spread of antibiotic resistance and protect public health.

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Reduction of Arcobacter at Two Conventional Wastewater Treatment Plants in Southern Arizona, USA

Pathogens ◽

10.3390/pathogens8040175 ◽

2019 ◽

Vol 8 (4) ◽

pp. 175 ◽

Cited By ~ 4

Author(s):

Ghaju Shrestha ◽

Sherchan ◽

Kitajima ◽

Tanaka ◽

Gerba ◽

...

Keyword(s):

Wastewater Treatment ◽

16S Rrna ◽

16S Rrna Gene ◽

Quantitative Pcr ◽

Pathogenic Bacteria ◽

Wastewater Treatment Plants ◽

The United States ◽

Rrna Gene ◽

Metagenomic Sequencing ◽

Wwtp Effluent

This study aimed to identify the bacterial community in two wastewater treatment plants (WWTPs) and to determine the occurrence and reduction of Arcobacter, along with virulence genes (ciaB and pldA). A total of 48 samples (24 influent and 24 effluent) were collected at two WWTPs in southern Arizona in the United States, monthly from August 2011 to July 2012. Bacterial DNA extract was utilized for 16S rRNA metagenomic sequencing. Quantification of Arcobacter 16S rRNA gene was conducted using a recently developed SYBR Green-based quantitative PCR assay. Among 847 genera identified, 113 (13%) were identified as potentially pathogenic bacteria. Arcobacter 16S rRNA gene was detected in all influent samples and ten (83%) and nine (75%) effluent samples at each plant, respectively. Log reduction ratios of Arcobacter 16S rRNA gene in Plant A and Plant B were 1.7 ± 0.9 (n = 10) and 2.3 ± 1.5 (n = 9), respectively. The ciaB gene was detected by quantitative PCR in eleven (92%) and twelve (100%) of 12 influent samples from Plant A and Plant B, respectively, while the pldA gene was detected in eight (67%) and six (50%) influent samples from Plant A and Plant B, respectively. The prevalence of potentially pathogenic bacteria in WWTP effluent indicated the need for disinfection before discharge into the environment.

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