scholarly journals Comparison of bacterial communities and antibiotic resistance genes in oxidation ditches and membrane bioreactors

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lifang Luo ◽  
Junqin Yao ◽  
Weiguo Liu ◽  
Lixin Yang ◽  
Hailong Li ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Activated Sludge ◽  
Relative Abundance ◽  
Resistance Genes ◽  
Bacterial Communities ◽  
Wastewater Treatment Plants ◽  
Antibiotic Resistance Genes ◽  
Membrane Bioreactors ◽  
Metagenomic Sequencing ◽  
Process Selection

AbstractOxidation ditches (ODs) and membrane bioreactors (MBRs) are widely used in wastewater treatment plants (WWTPs) with bacteria and antibiotic resistance genes (ARGs) running through the whole system. In this study, metagenomic sequencing was used to compare the bacterial communities and ARGs in the OD and MBR systems, which received the same influent in a WWTP located in Xinjiang, China. The results showed that the removal efficiency of pollutants by the MBR process was better than that by the OD process. The composition and the relative abundance of bacteria in activated sludge were similar at the phylum and genus levels and were not affected by process type. Multidrug, fluoroquinolones and peptides were the main ARG types for the two processes, with macB being the main ARG subtype, and the relative abundance of ARG subtypes in MBR effluent was much higher than that in the OD effluent. The mobile genetic elements (MGEs) in the activated sludge were mainly transposons (tnpA) and insertion sequences (ISs; IS91). These results provide a theoretical basis for process selection and controlling the spread of ARGs.

scholarly journals Metagenomic Community Composition and Resistome Analysis in a Full-scale Cold Climate Wastewater Treatment Plant

2021 ◽  
Author(s):  
Miguel Uyaguari
Keyword(s):  
Antibiotic Resistance ◽  
Wastewater Treatment ◽  
Activated Sludge ◽  
Relative Abundance ◽  
Resistance Genes ◽  
Wastewater Treatment Plant ◽  
Treatment Plant ◽  
Antibiotic Resistance Genes ◽  
Gene Copies ◽  
Final Effluent

Abstract Background: Wastewater treatment plants are an essential part of maintaining the health and safety of the general public. However, they are also an anthropogenic source of antibiotic resistance genes. In this study, we characterized the resistome, the distribution of classes 1-3 integron-integrase genes (intI1, intI2, and intI3) as mobile genetic element biomarkers, and the bacterial and phage community compositions in the North End Sewage Treatment Plant in Winnipeg, Manitoba. Samples were collected from raw sewage, returned activated sludge, final effluent, and dewatered sludge. A total of 28 bacterial and viral metagenomes were sequenced over two seasons, fall and winter. Integron-integrase genes, the 16S rRNA gene, and the coliform beta-glucuronidase gene were also quantified during this time period. Results: Bacterial classes observed above 1% relative abundance in all treatments were Actinobacteria (39.24% ± 0.25%), Beta-proteobacteria (23.99% ± 0.16%), Gamma-proteobacteria (11.06% ± 0.09%), and Alpha-proteobacteria (9.18 ± 0.04%). Families within the Caudovirales order: Siphoviridae (48.69% ± 0.10%), Podoviridae (23.99% ± 0.07%), and Myoviridae (19.94% ± 0.09%) were the dominant phage observed throughout the NESTP. The most abundant bacterial genera (in terms of average percent relative abundance) in influent, returned activated sludge, final effluent, and sludge, respectively, includes Mycobacterium (37.4%, 18.3%, 46.1%, and 7.7%), Acidovorax (8.9%, 10.8%, 5.4%, and 1.3%), and Polaromonas (2.5%, 3.3%, 1.4%, and 0.4%).The most abundant class of antibiotic resistance in bacterial samples was tetracycline resistance (17.86% ± 0.03%) followed by peptide antibiotics (14.24% ± 0.03%), and macrolides (10.63% ± 0.02%). Similarly, the phage samples contained a higher prevalence of macrolide (30.12% ± 0.30%), peptide antibiotic (10.78% ± 0.13%), and tetracycline (8.69% ± 0.11%) resistance. In addition, intI1 was the most abundant integron-integrase gene throughout treatment (1.14x104 gene copies/mL) followed by intI3 (4.97x103 gene copies/mL) while intI2 abundance remained low (6.4x101 gene copies/mL).Conclusions: The wastewater treatment plant successfully reduced the abundance of bacteria, DNA bacteriophages, and antibiotic resistance genes although many of them still remained in effluent and biosolids. The presence of integron-integrase genes throughout treatment and in effluent suggests that antibiotic resistance genes could be actively disseminating resistance between both environmental and pathogenic bacteria.

scholarly journals Metagenomic Profiles of Antibiotic Resistance Genes in Activated Sludge, Dewatered Sludge and Bioaerosols

Water ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1516
Author(s):  
Il Han ◽  
Keunje Yoo
Keyword(s):  
Antibiotic Resistance ◽  
Wastewater Treatment ◽  
Activated Sludge ◽  
Resistance Genes ◽  
Wastewater Treatment Plants ◽  
Antibiotic Resistance Genes ◽  
Illumina Hiseq ◽  
Wastewater Treatment Process ◽  
Dewatered Sludge ◽  
Scientific Attention

Wastewater treatment plants (WWTPs) have been considered hotspots for the development and dissemination of antibiotic resistance in the environment. Although researchers have reported a significant increase in bioaerosols in WWTPs, the associated bacterial taxa, antibiotic resistance genes (ARGs), and mobile genetic elements (MGEs) remain relatively unknown. In this study, we have investigated the abundance and occurrences of ARGs and MGEs, as well as the bacterial community compositions in activated sludge (AS), dewatered sludge (DS) and bioaerosols (BA) in a WWTP. In total, 153 ARG subtypes belonging to 19 ARG types were identified by the broad scanning of metagenomic profiles obtained using Illumina HiSeq. The results indicated that the total occurrences and abundances of ARGs in AS and DS samples were significantly higher than those in BA samples (p < 0.05). However, some specific ARG types related to sulfonamide, tetracycline, macrolide resistance were present in relatively high abundance in BA samples. Similar to many other full-scale WWTPs, the Proteobacteria (58%) and Bacteroidetes (18%) phyla were dominant in the AS and DS samples, while the Firmicutes (25%) and Actinobacteria (20%) phyla were the most dominant in the BA samples. Although the abundance of genes related to plasmids and integrons in bioaerosols were two to five times less than those in AS and DS samples, different types of MGEs were observed in BA samples. These results suggest that comprehensive analyses of resistomes in BA are required to better understand the emergence of both ARGs and MGEs in the wastewater treatment process due to the significant increase of scientific attention toward bioaerosols effects.

scholarly journals High-throughput profiling of antibiotic resistance genes in wastewater: comparison between a pond system in Namibia and an activated sludge treatment in Germany

2020 ◽  
Vol 18 (6) ◽  
pp. 867-878
Author(s):  
Shelesh Agrawal ◽  
Laura Orschler ◽  
Jochen Sinn ◽  
Susanne Lackner
Keyword(s):  
Antibiotic Resistance ◽  
Activated Sludge ◽  
Resistance Genes ◽  
Wastewater Treatment Plants ◽  
Wide Spectrum ◽  
Antibiotic Resistance Genes ◽  
Developed Country ◽  
Pond System ◽  
Occurrence Patterns ◽  
Influent Wastewater

Abstract There are increasing concerns about wastewater treatment plants (WWTPs) acting as hotspots for antibiotic resistance genes (ARG). However, their role largely depends upon the treatment methods and antibiotics in the wastewater. To better understand these influences, we compared the occurrence and fate of ARG between a pond system in a developing country (Namibia) and an advanced WWTP (activated sludge system) in a developed country (Germany). A targeted metagenomic approach was used to investigate the wide-spectrum profiles of ARGs and their co-occurrence patterns at both locations. In total, 93 ARG subtypes were found in the German influent wastewater, 277 in the Namibian influent wastewater. The abundant ARG types found in Namibia and Germany differed, especially for multidrug resistance genes. The differences in occurrence and reduction can help to understand the performance of simple WWTP such as pond systems common in Namibia, where direct contact with wastewater is a potential risk for contamination.

scholarly journals Vliv adaptace aktivovaného kalu na biodegradaci antibiotik a akumulaci genů resistence

Entecho ◽  
2019 ◽  
Vol 2 (1) ◽  
pp. 6-12
Author(s):  
Ivan Karpíšek ◽  
Jitka Zachová ◽  
Dana Vejmelková ◽  
Vladimír Sýkora
Keyword(s):  
Antibiotic Resistance ◽  
Activated Sludge ◽  
Resistance Genes ◽  
Wastewater Treatment Plants ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Antibiotic Resistance Genes ◽  
Low Concentrations ◽  
Pcr Method

Aktivovaný kal na čistírnách odpadních vod je neustále vystavován nízkým koncentracím antimikrobiálních látek a dalších léčiv. To vyvolává otázku, jak mikroorganismy k těmto látkám na čistírně odpadních vod přistupují. Zda jsou schopny se v tomto prostředí na tyto látky adaptovat, degradovat je, případně je využít jako substrát. Nebo jestli jsou tyto látky aktivovaným kalem opomíjeny. Pro posouzení adaptace aktivovaného kalu byla využita metoda PCR pro sledování genů resistence a testy biologické rozložitelnosti. Pro testy byl využit aktivovaný kal z ČOV a kal adaptovaný v laboratorních SBR modelech při koncentracích antibiotik 500 ng∙l−1 a 500 μg∙l−1. Biologická rozložitelnost byla posuzována dle normy ČSN ISO 14593. Testované látky byly sledovány pomocí skupinového stanovení celkového anorganického uhlíku. Jako testované látky byly vybrány: benzylpenicilin, ampicilin, streptomycin, erythromycin, chloramfenikol, sulfamethoxazol a trimetoprim. Aktivovaný kal z čistírny odpadních vod neměl vyvinutou aktivitu k biodegradaci testovaných antibiotik. Je pravděpodobné, že vysoké zatížení snadno biologicky rozložitelným substrátem a krátké zdržení odpadní vody na ČOV, vede k tomu, že mikroorganismy aktivovaného kalu nejsou nuceny tyto látky aktivně utilizovat a brání se jim pouze tvorbou obranných mechanismů pomocí genů antibiotické resistence. Nízké koncentrace antibiotik v SBR modelech vytvářely selekční tlak na mikroorganismy a podněcovaly šíření genů antibiotické resistence. English Activated sludge in wastewater treatment plants is constantly exposed to low concentrations of antimicrobials and other drugs. This raises the question of how microorganisms approach to these substances in the sewage treatment plant. Whether they can adapt, degrade, or use antibiotics as a substrate in this environment or the activated sludge neglects these substances. To assess the adaptation of activated sludge, the PCR method for monitoring antibiotic resistance genes and biodegradability tests were used. These tests were carried out with activated sludge from WWTP and sludge adapted in laboratory SBR models at 500 ng∙l−1 and 500 μg∙l−1 of chosen antibiotics. Their biodegradability was assessed according to ČSN ISO 14593. The tested substances were monitored by group determination of total inorganic carbon. The chosen substances were: benzylpenicillin, ampicillin, streptomycin, erythromycin, chloramphenicol, sulfamethoxazole and trimethoprim. Activated sludge had no developed activity for biodegradation of tested antibiotics. It is likely that the high load of readily biodegradable substrate and the short retention of the wastewater at the WWTP lead to the activated sludge not being forced to actively utilize these substances and will only prevent from them by forming defence mechanisms using antibiotic resistance genes. Low concentrations of antibiotics in SBR models produced selective pressure on microorganisms and stimulated the spread of antibiotic resistance genes.

scholarly journals Metagenomic community composition and resistome analysis in a full-scale cold climate wastewater treatment plant

2022 ◽  
Vol 17 (1) ◽  
Author(s):  
Paul Jankowski ◽  
Jaydon Gan ◽  
Tri Le ◽  
Michaela McKennitt ◽  
Audrey Garcia ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Wastewater Treatment ◽  
Activated Sludge ◽  
Relative Abundance ◽  
Resistance Genes ◽  
Treatment Plant ◽  
Antibiotic Resistance Genes ◽  
Cold Climate ◽  
Gene Copies ◽  
Final Effluent

Abstract Background Wastewater treatment plants are an essential part of maintaining the health and safety of the general public. However, they are also an anthropogenic source of antibiotic resistance genes. In this study, we characterized the resistome, the distribution of classes 1–3 integron-integrase genes (intI1, intI2, and intI3) as mobile genetic element biomarkers, and the bacterial and phage community compositions in the North End Sewage Treatment Plant in Winnipeg, Manitoba. Samples were collected from raw sewage, returned activated sludge, final effluent, and dewatered sludge. A total of 28 bacterial and viral metagenomes were sequenced over two seasons, fall and winter. Integron-integrase genes, the 16S rRNA gene, and the coliform beta-glucuronidase gene were also quantified during this time period. Results Bacterial classes observed above 1% relative abundance in all treatments were Actinobacteria (39.24% ± 0.25%), Beta-proteobacteria (23.99% ± 0.16%), Gamma-proteobacteria (11.06% ± 0.09%), and Alpha-proteobacteria (9.18 ± 0.04%). Families within the Caudovirales order: Siphoviridae (48.69% ± 0.10%), Podoviridae (23.99% ± 0.07%), and Myoviridae (19.94% ± 0.09%) were the dominant phage observed throughout the NESTP. The most abundant bacterial genera (in terms of average percent relative abundance) in influent, returned activated sludge, final effluent, and sludge, respectively, includes Mycobacterium (37.4%, 18.3%, 46.1%, and 7.7%), Acidovorax (8.9%, 10.8%, 5.4%, and 1.3%), and Polaromonas (2.5%, 3.3%, 1.4%, and 0.4%). The most abundant class of antibiotic resistance in bacterial samples was tetracycline resistance (17.86% ± 0.03%) followed by peptide antibiotics (14.24% ± 0.03%), and macrolides (10.63% ± 0.02%). Similarly, the phage samples contained a higher prevalence of macrolide (30.12% ± 0.30%), peptide antibiotic (10.78% ± 0.13%), and tetracycline (8.69% ± 0.11%) resistance. In addition, intI1 was the most abundant integron-integrase gene throughout treatment (1.14 × 104 gene copies/mL) followed by intI3 (4.97 × 103 gene copies/mL) while intI2 abundance remained low (6.4 × 101 gene copies/mL). Conclusions Wastewater treatment successfully reduced the abundance of bacteria, DNA phage and antibiotic resistance genes although many antibiotic resistance genes remained in effluent and biosolids. The presence of integron-integrase genes throughout treatment and in effluent suggests that antibiotic resistance genes could be actively disseminating resistance between both environmental and pathogenic bacteria.

scholarly journals A glyphosate-based herbicide cross-selects for antibiotic resistance genes in bacterioplankton communities

2021 ◽  
Author(s):  
Naíla Barbosa da Costa ◽  
Marie-Pier Hébert ◽  
Vincent Fugère ◽  
Yves Terrat ◽  
Gregor Fussmann ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Resistance Genes ◽  
Bacterial Communities ◽  
Antibiotic Resistance Genes ◽  
Efflux Pumps ◽  
Cross Resistance ◽  
Resistant Bacteria ◽  
Metagenomic Sequencing ◽  
Resistance Mutations ◽  
Variation Explained

Agrochemicals often contaminate freshwater bodies, affecting microbial communities that underlie aquatic food webs. For example, Roundup, a widely-used glyphosate-based herbicide (GBH), has the potential to indirectly select for antibiotic resistant bacteria. Such cross-selection could occur, for example, if the same genes (e.g. encoding efflux pumps) confer resistance to both glyphosate and antibiotics. To test for cross-resistance in natural aquatic bacterial communities, we added Roundup to 1,000-L mesocosms filled with water from a pristine lake. Over 57 days, we tracked changes in bacterial communities with shotgun metagenomic sequencing, and annotated metagenome-assembled genomes (MAGs) for the presence of known antibiotic resistance genes (ARGs), plasmids, and resistance mutations in the enzyme targeted by glyphosate (enolpyruvyl-shikimate-3-phosphate synthase; EPSPS). We found that high doses of GBH significantly increased ARG frequency and selected for multidrug efflux pumps in particular. The relative abundance of MAGs after a high dose of GBH was predictable based on the number of ARGs encoded in their genomes (17% of variation explained) and, to a lesser extent, by resistance mutations in EPSPS (2% of variation explained). Together, these results indicate that GBHs have the potential to cross-select for antibiotic resistance in natural freshwater bacteria.

scholarly journals Vliv adaptace aktivovaného kalu na biodegradaci antibiotik a akumulaci genů resistence

Entecho ◽  
2019 ◽  
Vol 2 (1) ◽  
pp. 6-12
Author(s):  
Ivan Kapríšek ◽  
Jitka Zachová ◽  
Dana Vejmelková ◽  
Vladimír Sýkora
Keyword(s):  
Antibiotic Resistance ◽  
Activated Sludge ◽  
Resistance Genes ◽  
Wastewater Treatment Plants ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Antibiotic Resistance Genes ◽  
Low Concentrations ◽  
Pcr Method

Aktivovaný kal na čistírnách odpadních vod je neustále vystavován nízkým koncentracím antimikrobiálních látek a dalších léčiv. To vyvolává otázku, jak mikroorganismy k těmto látkám na čistírně odpadních vod přistupují. Zda jsou schopny se v tomto prostředí na tyto látky adaptovat, degradovat je, případně je využít jako substrát. Nebo jestli jsou tyto látky aktivovaným kalem opomíjeny. Pro posouzení adaptace aktivovaného kalu byla využita metoda PCR pro sledování genů resistence a testy biologické rozložitelnosti. Pro testy byl využit aktivovaný kal z ČOV a kal adaptovaný v laboratorních SBR modelech při koncentracích antibiotik 500 ng∙l−1 a 500 μg∙l−1. Biologická rozložitelnost byla posuzována dle normy ČSN ISO 14593. Testované látky byly sledovány pomocí skupinového stanovení celkového anorganického uhlíku. Jako testované látky byly vybrány: benzylpenicilin, ampicilin, streptomycin, erythromycin, chloramfenikol, sulfamethoxazol a trimetoprim. Aktivovaný kal z čistírny odpadních vod neměl vyvinutou aktivitu k biodegradaci testovaných antibiotik. Je pravděpodobné, že vysoké zatížení snadno biologicky rozložitelným substrátem a krátké zdržení odpadní vody na ČOV, vede k tomu, že mikroorganismy aktivovaného kalu nejsou nuceny tyto látky aktivně utilizovat a brání se jim pouze tvorbou obranných mechanismů pomocí genů antibiotické resistence. Nízké koncentrace antibiotik v SBR modelech vytvářely selekční tlak na mikroorganismy a podněcovaly šíření genů antibiotické resistence. English Activated sludge in wastewater treatment plants is constantly exposed to low concentrations of antimicrobials and other drugs. This raises the question of how microorganisms approach to these substances in the sewage treatment plant. Whether they can adapt, degrade, or use antibiotics as a substrate in this environment or the activated sludge neglects these substances. To assess the adaptation of activated sludge, the PCR method for monitoring antibiotic resistance genes and biodegradability tests were used. These tests were carried out with activated sludge from WWTP and sludge adapted in laboratory SBR models at 500 ng∙l−1 and 500 μg∙l−1 of chosen antibiotics. Their biodegradability was assessed according to ČSN ISO 14593. The tested substances were monitored by group determination of total inorganic carbon. The chosen substances were: benzylpenicillin, ampicillin, streptomycin, erythromycin, chloramphenicol, sulfamethoxazole and trimethoprim. Activated sludge had no developed activity for biodegradation of tested antibiotics. It is likely that the high load of readily biodegradable substrate and the short retention of the wastewater at the WWTP lead to the activated sludge not being forced to actively utilize these substances and will only prevent from them by forming defence mechanisms using antibiotic resistance genes. Low concentrations of antibiotics in SBR models produced selective pressure on microorganisms and stimulated the spread of antibiotic resistance genes.

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