scholarly journals Estrogen Degraders and Estrogen Degradation Pathway Identified in an Activated Sludge

2018 ◽  
Vol 84 (10) ◽  
Author(s):  
Yi-Lung Chen ◽  
Han-Yi Fu ◽  
Tzong-Huei Lee ◽  
Chao-Jen Shih ◽  
Lina Huang ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plants ◽  
Sewage Treatment Plant ◽  
Degradation Pathway ◽  
Bacterial Degradation ◽  
Ring Cleavage ◽  
Main Process ◽  
Content Type ◽  
Degrading Bacteria

ABSTRACTThe environmental release and fate of estrogens are becoming an increasing public concern. Bacterial degradation has been considered the main process for eliminating estrogens from wastewater treatment plants. Various bacterial isolates are reportedly capable of aerobic estrogen degradation, and several estrogen degradation pathways have been proposed in proteobacteria and actinobacteria. However, the ecophysiological relevance of estrogen-degrading bacteria in the environment is unclear. In this study, we investigated the estrogen degradation pathway and corresponding degraders in activated sludge collected from the Dihua Sewage Treatment Plant, Taipei, Taiwan. Cultivation-dependent and cultivation-independent methods were used to assess estrogen biodegradation in the collected activated sludge. Estrogen metabolite profile analysis revealed the production of pyridinestrone acid and two A/B-ring cleavage products in activated sludge incubated with estrone (1 mM), which are characteristic of the 4,5-secopathway. PCR-based functional assays detected sequences closely related to alphaproteobacterialoecC, a key gene of the 4,5-secopathway. Metagenomic analysis suggested thatNovosphingobiumspp. are major estrogen degraders in estrone-amended activated sludge.Novosphingobiumsp. strain SLCC, an estrone-degrading alphaproteobacterium, was isolated from the examined activated sludge. The general physiology and metabolism of this strain were characterized. Pyridinestrone acid and the A/B-ring cleavage products were detected in estrone-grown strain SLCC cultures. The production of pyridinestrone acid was also observed during the aerobic incubation of strain SLCC with 3.7 nM (1 μg/liter) estrone. This concentration is close to that detected in many natural and engineered aquatic ecosystems. The presented data suggest the ecophysiological relevance ofNovosphingobiumspp. in activated sludge.IMPORTANCEEstrogens, which persistently contaminate surface water worldwide, have been classified as endocrine disruptors and human carcinogens. We contribute new knowledge on the major estrogen biodegradation pathway and estrogen degraders in wastewater treatment plants. This study considerably advances the understanding of environmental estrogen biodegradation, which is instrumental for the efficient elimination of these hazardous pollutants. Moreover, this study substantially improves the understanding of microbial estrogen degradation in the environment.

scholarly journals Steroid Degradation in Comamonas testosteroni TA441: Identification of the Entire β-Oxidation Cycle of the Cleaved B Ring

2019 ◽  
Vol 85 (20) ◽  
Author(s):  
Masae Horinouchi ◽  
Hiroyuki Koshino ◽  
Michal Malon ◽  
Hiroshi Hirota ◽  
Toshiaki Hayashi
Keyword(s):  
Gene Clusters ◽  
Degradation Process ◽  
Degradation Pathway ◽  
Ring Cleavage ◽  
Comamonas Testosteroni ◽  
Content Type ◽  
Coa Transferase ◽  
Degrading Bacteria ◽  
Globally Distributed

ABSTRACT Comamonas testosteroni TA441 degrades steroids via aromatization of the A ring, followed by degradation of 9,17-dioxo-1,2,3,4,10,19-hexanorandrostan-5-oic acid, mainly by β-oxidation. In this study, we revealed that 7β,9α-dihydroxy-17-oxo-1,2,3,4,10,19-hexanorandrostanoic acid-coenzyme A (CoA) ester is dehydrogenated by (3S)-3-hydroxylacyl CoA-dehydrogenase, encoded by scdE (ORF27), and then the resultant 9α-hydroxy-7,17-dioxo-1,2,3,4,10,19-hexanorandrostan-5-oic acid-CoA ester is converted by 3-ketoacyl-CoA transferase, encoded by scdF (ORF23). With these results, the whole cycle of β-oxidation on the side chain at C-8 of 9,17-dioxo-1,2,3,4,10,19-hexanorandrostan-5-oic acid is clarified; 9-hydroxy-17-oxo-1,2,3,4,10,19-hexanorandrostan-5-oic acid-CoA ester is dehydrogenated at C-6 by ScdC1C2, followed by hydration by ScdD. 7β,9α-Dihydroxy-17-oxo-1,2,3,4,10,19-hexanorandrostanoic acid-CoA ester then is dehydrogenated by ScdE to be converted to 9α-hydroxy-17-oxo-1,2,3,4,5,6,10,19-octanorandrostan-7-oic acid-CoA ester and acetyl-CoA by ScdF. ScdF is an ortholog of FadA6 in Mycobacterium tuberculosis H37Rv, which was reported as a 3-ketoacyl-CoA transferase involved in C ring cleavage. We also obtained results suggesting that ScdF is also involved in C ring cleavage, but further investigation is required for confirmation. ORF25 and ORF26, located between scdF and scdE, encode enzymes belonging to the amidase superfamily. Disrupting either ORF25 or ORF26 did not affect steroid degradation. Among the bacteria having gene clusters similar to those of tesB to tesR, some have both ORF25- and ORF26-like proteins or only an ORF26-like protein, but others do not have either ORF25- or ORF26-like proteins. ORF25 and ORF26 are not crucial for steroid degradation, yet they might provide clues to elucidate the evolution of bacterial steroid degradation clusters. IMPORTANCE Studies on bacterial steroid degradation were initiated more than 50 years ago primarily to obtain materials for steroid drugs. Steroid-degrading bacteria are globally distributed, and the role of bacterial steroid degradation in the environment as well as in relation to human health is attracting attention. The overall aerobic degradation of the four basic steroidal rings has been proposed; however, there is still much to be revealed to understand the complete degradation pathway. This study aims to uncover the whole steroid degradation process in Comamonas testosteroni TA441 as a model of steroid-degrading bacteria. C. testosteroni is one of the most studied representative steroid-degrading bacteria and is suitable for exploring the degradation pathway, because the involvement of degradation-related genes can be determined by gene disruption. Here, we elucidated the entire β-oxidation cycle of the cleaved B ring. This cycle is essential for the following C and D ring cleavage.

scholarly journals Reliability of removal of selected pollutants in different technological solutions of household wastewater treatment plants

2017 ◽  
Vol 35 (1) ◽  
pp. 141-148 ◽  
Author(s):  
Michał Marzec
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Total Suspended Solids ◽  
Hybrid Reactor ◽  
Limit Values

AbstractThe reliability of removal of selected contaminants in three technological solutions of the household sewage treatment plants was analysed in this paper. The reliability of the sewage treatment plant with activated sludge, sprinkled biological deposit and hybrid reactor (activated sludge and immersed trickling filter) was analyzed. The analysis was performed using the Weibull method for basic indicators of impurities, BOD5, COD and total suspended solids. The technological reliability of the active sludge treatment plant was 70% for BOD5, 87% for COD and 66% for total suspended solids. In the sewage treatment plant with a biological deposit, the reliability values determined were: 30% (BOD5), 60% (COD) and 67% (total suspended solids). In a treatment plant with a hybrid reactor, 30% of the BOD5and COD limit values were exceeded, while 30% of the total suspended solids were exceeded. The reliability levels are significantly lower than the acceptable levels proposed in the literature, which means that the wastewater discharged from the analysed wastewater treatment plants often exceeds the limit values of indicators specified in currently valid in Poland Regulation of the Minister of Environment for object to 2000 population equivalent.

scholarly journals Casimicrobium huifangae gen. nov., sp. nov., a Ubiquitous “Most-Wanted” Core Bacterial Taxon from Municipal Wastewater Treatment Plants

2019 ◽  
Vol 86 (4) ◽  
Author(s):  
Yang Song ◽  
Cheng-Ying Jiang ◽  
Zong-Lin Liang ◽  
Bao-Jun Wang ◽  
Yong Jiang ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Carbon Sources ◽  
Short Chain Fatty Acids ◽  
Municipal Wastewater Treatment ◽  
Content Type ◽  
Bacterial Taxon ◽  
Municipal Wastewater Treatment Plants

ABSTRACT Microorganisms in wastewater treatment plants (WWTPs) play a key role in the removal of pollutants from municipal and industrial wastewaters. A recent study estimated that activated sludge from global municipal WWTPs harbors 1 × 109 to 2 × 109 microbial species, the majority of which have not yet been cultivated, and 28 core taxa were identified as “most-wanted” ones (L. Wu, D. Ning, B. Zhang, Y. Li, et al., Nat Microbiol 4:1183–1195, 2019, https://doi.org/10.1038/s41564-019-0426-5). Cultivation and characterization of the “most-wanted” core bacteria are critical to understand their genetic, physiological, phylogenetic, and ecological traits, as well as to improve the performance of WWTPs. In this study, we isolated a bacterial strain, designated SJ-1, that represents a novel cluster within Betaproteobacteria and corresponds to OTU_16 within the 28 core taxa in the “most-wanted” list. Strain SJ-1 was identified and nominated as Casimicrobium huifangae gen. nov., sp. nov., of a novel family, Casimicrobiaceae. C. huifangae is ubiquitously distributed and is metabolically versatile. In addition to mineralizing various carbon sources (including carbohydrates, aromatic compounds, and short-chain fatty acids), C. huifangae is capable of nitrate reduction and phosphorus accumulation. The population of C. huifangae accounted for more than 1% of the bacterial population of the activated sludge microbiome from the Qinghe WWTP, which showed seasonal dynamic changes. Cooccurrence analysis suggested that C. huifangae was an important module hub in the bacterial network of Qinghe WWTP. IMPORTANCE The activated sludge process is the most widely applied biotechnology and is one of the best ecosystems to address microbial ecological principles. Yet, the cultivation of core bacteria and the exploration of their physiology and ecology are limited. In this study, the core and novel bacterial taxon C. huifangae was cultivated and characterized. This study revealed that C. huifangae functioned as an important module hub in the activated sludge microbiome, and it potentially plays an important role in municipal wastewater treatment plants.

scholarly journals Steroid Degradation in Comamonas testosteroni TA441: Identification of Metabolites and the Genes Involved in the Reactions Necessary before D-Ring Cleavage

2018 ◽  
Vol 84 (22) ◽  
Author(s):  
Masae Horinouchi ◽  
Hiroyuki Koshino ◽  
Michal Malon ◽  
Hiroshi Hirota ◽  
Toshiaki Hayashi
Keyword(s):  
Wastewater Treatment Plants ◽  
Degradation Process ◽  
Ring Cleavage ◽  
Comamonas Testosteroni ◽  
Content Type ◽  
Oxidative Reactions ◽  
Degrading Bacteria ◽  
Steroid Drugs ◽  
Globally Distributed

ABSTRACT Bacterial steroid degradation has been studied mainly with Rhodococcus equi (Nocardia restrictus) and Comamonas testosteroni as representative steroid degradation bacteria for more than 50 years. The primary purpose was to obtain materials for steroid drugs, but recent studies showed that many genera of bacteria (Mycobacterium, Rhodococcus, Pseudomonas, etc.) degrade steroids and that steroid-degrading bacteria are globally distributed and found particularly in wastewater treatment plants, the soil, plant rhizospheres, and the marine environment. The role of bacterial steroid degradation in the environment is, however, yet to be revealed. To uncover the whole steroid degradation process in a representative steroid-degrading bacterium, C. testosteroni, to provide basic information for further studies on the role of bacterial steroid degradation, we elucidated the two indispensable oxidative reactions and hydration before D-ring cleavage in C. testosteroni TA441. In bacterial oxidative steroid degradation, A- and B-rings of steroids are cleaved to produce 2-hydroxyhexa-2,4-dienoic acid and 9,17-dioxo-1,2,3,4,10,19-hexanorandrostan-5-oic acid. The latter compound was revealed to be degraded to the coenzyme A (CoA) ester of 9α-hydroxy-17-oxo-1,2,3,4,5,6,10,19-octanorandrostan-7-oic acid, which is converted to the CoA ester of 9,17-dioxo-1,2,3,4,5,6,10,19-octanorandrostan-7-oic acid by ORF31-encoded hydroxylacyl dehydrogenase (ScdG), followed by conversion to the CoA ester of 9,17-dioxo-1,2,3,4,5,6,10,19-octanorandrost-8(14)-en-7-oic acid by ORF4-encoded acyl-CoA dehydrogenase (ScdK). Then, a water molecule is added by the ORF5-encoded enoyl-CoA hydratase (ScdY), which leads to the cleavage of the D-ring. The conversion by ScdG is presumed to be a reversible reaction. The elucidated pathway in C. testosteroni TA441 is different from the corresponding pathways in Mycobacterium tuberculosis H37Rv. IMPORTANCE Studies on representative steroid degradation bacteria Rhodococcus equi (Nocardia restrictus) and Comamonas testosteroni were initiated more than 50 years ago primarily to obtain materials for steroid drugs. A recent study showed that steroid-degrading bacteria are globally distributed and found particularly in wastewater treatment plants, the soil, plant rhizospheres, and the marine environment, but the role of bacterial steroid degradation in the environment is yet to be revealed. This study aimed to uncover the whole steroid degradation process in C. testosteroni TA441, in which major enzymes for steroidal A- and B-ring cleavage were elucidated, to provide basic information for further studies on bacterial steroid degradation. C. testosteroni is suitable for exploring the degradation pathway because the involvement of degradation-related genes can be determined by gene disruption. We elucidated the two indispensable oxidative reactions and hydration before D-ring cleavage, which appeared to differ from those present in Mycobacterium tuberculosis H37Rv.

scholarly journals Role of IncP-1β Plasmids pWDL7::rfpand pNB8c in Chloroaniline Catabolism as Determined by Genomic and Functional Analyses

2011 ◽  
Vol 78 (3) ◽  
pp. 828-838 ◽  
Author(s):  
J. E. Król ◽  
J. T. Penrod ◽  
H. McCaslin ◽  
L. M. Rogers ◽  
H. Yano ◽  
...  
Keyword(s):  
Single Copy ◽  
Degradation Pathway ◽  
Bacterial Degradation ◽  
Ring Cleavage ◽  
Close Relative ◽  
Broad Host Range ◽  
Content Type ◽  
Aromatic Ring Cleavage ◽  
Functional Analyses

ABSTRACTBroad-host-range catabolic plasmids play an important role in bacterial degradation of man-made compounds. To gain insight into the role of these plasmids in chloroaniline degradation, we determined the first complete nucleotide sequences of an IncP-1 chloroaniline degradation plasmid, pWDL7::rfpand its close relative pNB8c, as well as the expression pattern, function, and bioaugmentation potential of the putative 3-chloroaniline (3-CA) oxidation genes. Based on phylogenetic analysis of backbone proteins, both plasmids are members of a distinct clade within the IncP-1β subgroup. The plasmids are almost identical, but whereas pWDL7::rfpcarries a duplicate inverted catabolic transposon, Tn6063, containing a putative 3-CA oxidation gene cluster,dcaQTA1A2BR, pNB8c contains only a single copy of the transposon. No genes for an aromatic ring cleavage pathway were detected on either plasmid, suggesting that only the upper 3-CA degradation pathway was present. ThedcaA1A2Bgene products expressed from a high-copy-number vector were shown to convert 3-CA to 4-chlorocatechol inEscherichia coli. Slight differences in thedcapromoter region between the plasmids and lack of induction of transcription of the pNB8cdcagenes by 3-CA may explain previous findings that pNB8C does not confer 3-CA transformation. Bioaugmentation of activated sludge with pWDL7::rfpaccelerated removal of 3-CA, but only in the presence of an additional carbon source. Successful bioaugmentation requires complementation of the upper pathway genes with chlorocatechol cleavage genes in indigenous bacteria. The genome sequences of these plasmids thus help explain the molecular basis of their catabolic activities.

Analysis and balance of phosphorous removal from wastewater at urban wastewater treatment plant

2020 ◽  
Vol 15 (2) ◽  
pp. 142-151
Author(s):  
Peter Lukac ◽  
Lubos Jurik
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plant ◽  
Wastewater Treatment Plants ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Phosphorus Recovery ◽  
Anaerobic Sludge ◽  
Biological Phosphorus Removal ◽  
The Mean

Abstract:Phosphorus is a major substance that is needed especially for agricultural production or for the industry. At the same time it is an important component of wastewater. At present, the waste management priority is recycling and this requirement is also transferred to wastewater treatment plants. Substances in wastewater can be recovered and utilized. In Europe (in Germany and Austria already legally binding), access to phosphorus-containing sewage treatment is changing. This paper dealt with the issue of phosphorus on the sewage treatment plant in Nitra. There are several industrial areas in Nitra where record major producers in phosphorus production in sewage. The new wastewater treatment plant is built as a mechanicalbiological wastewater treatment plant with simultaneous nitrification and denitrification, sludge regeneration, an anaerobic zone for biological phosphorus removal at the beginning of the process and chemical phosphorus precipitation. The sludge management is anaerobic sludge stabilization with heating and mechanical dewatering of stabilized sludge and gas management. The aim of the work was to document the phosphorus balance in all parts of the wastewater treatment plant - from the inflow of raw water to the outflow of purified water and the production of excess sludge. Balancing quantities in the wastewater treatment plant treatment processes provide information where efficient phosphorus recovery could be possible. The mean daily value of P tot is approximately 122.3 kg/day of these two sources. The mean daily value of P tot is approximately 122.3 kg/day of these two sources. There are also two outflows - drainage of cleaned water to the recipient - the river Nitra - 9.9 kg Ptot/day and Ptot content in sewage sludge - about 120.3 kg Ptot/day - total 130.2 kg Ptot/day.

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

2019 ◽  
Vol 9 (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.

scholarly journals Deep learning-based morphology classification of activated sludge flocs in wastewater treatment plants

2021 ◽  
Author(s):  
Hisashi Satoh ◽  
Yukari Kashimoto ◽  
Naoki Takahashi ◽  
Takashi Tsujimura
Keyword(s):  
Wastewater Treatment ◽  
Deep Learning ◽  
Activated Sludge ◽  
Morphological Change ◽  
Wastewater Treatment Plants ◽  
Filamentous Bacteria ◽  
Sludge Flocs

A deep learning-based two-label classifier 1 recognized a 20% morphological change in the activated flocs. Classifier-2 quantitatively recognized an abundance of filamentous bacteria in activated flocs.

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