1
|
Hao Z, He S, Wang Q, Luo Y, Tu C, Wu W, Jiang H. Nanoplastics enhance the denitrification process and microbial interaction network in wetland soils. WATER RESEARCH 2024; 259:121796. [PMID: 38820736 DOI: 10.1016/j.watres.2024.121796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 05/15/2024] [Accepted: 05/16/2024] [Indexed: 06/02/2024]
Abstract
With the widespread presence of plastic waste in ecosystems, it is imperative to understand the response of natural processes to micro- and nanoplastic pollution pressures. However, the effects of nanoplastics on biogeochemical cycles are still overlooked and controversial. This study investigated the effects of three particle sizes (100 μm, 7 μm, and 80 nm) of polystyrene (PS) micro/nanoplastics (0.08 % of mass concentration) on denitrification processes and nirS/nirK denitrifying bacterial communities in wetland soils. The results indicated that PS nanoplastics were found to significantly enhance denitrification rates from 21.30 to 54.73 μmol N2·h-1·kg-1, increasing by 1.57 times compared to the control. Exposure to nanoplastics caused shifts in the composition and structure of the nirS-type denitrifier community. LEfSe analysis, random forest, and Mantel tests revealed that nirS denitrifying bacteria, especially Sideroxydans, played a pivotal role in driving denitrification rates (Mantel's R = 0.24, p = 0.002), likely due to the faster release of organic substrates from nanoplastics. Microbial co-occurrence networks demonstrated that nanoplastic amendments fostered a denser denitrifier network and led to shifts in keystone species. Sideroxydans appeared more likely to cooperate with other bacteria, such as Burkholderiales, to complete denitrification processes. This study suggests that nanoplastics are a potentially stronger driver of denitrification than microplastics, providing insight into the impact of plastic pollutants on biogeochemical cycling in natural wetland ecosystems. Given the widespread distribution of wetlands, the potential increase in gaseous nitrogen emissions due to nanoplastics pollution warrants attention.
Collapse
Affiliation(s)
- Zheng Hao
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
| | - Shangwei He
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; Jiangsu Key Laboratory for Bioresources of Saline Soils, Jiangsu Synthetic Innovation Center for Coastal Bio-agriculture, Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection, School of Wetland, Yancheng Teachers University, Yancheng 224007, China
| | - Qianhong Wang
- Changjiang Nanjing Waterway Engineering Bureau, Nanjing 210011, China
| | - Yongming Luo
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chen Tu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenbin Wu
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Helong Jiang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
| |
Collapse
|
2
|
Li D, Deng Y, Liu L, Wang J, Huang Z, Zhang X. Analysis of heavy metal and polycyclic aromatic hydrocarbon pollution characteristics of a typical metal rolling industrial site based on data mining. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2024; 46:146. [PMID: 38578375 DOI: 10.1007/s10653-024-01928-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 02/20/2024] [Indexed: 04/06/2024]
Abstract
With the transformation and upgrading of industries, the environmental problems caused by industrial residual contaminated sites are becoming increasingly prominent. Based on actual investigation cases, this study analyzed the soil pollution status of a remaining sites of the copper and zinc rolling industry, and found that the pollutants exceeding the screening values included Cu, Ni, Zn, Pb, total petroleum hydrocarbons and 6 polycyclic aromatic hydrocarbon monomers. Based on traditional analysis methods such as the correlation coefficient and spatial distribution, combined with machine learning methods such as SOM + K-means, it is inferred that the heavy metal Zn/Pb may be mainly related to the production history of zinc rolling. Cu/Ni may be mainly originated from the production history of copper rolling. PAHs are mainly due to the incomplete combustion of fossil fuels in the melting equipment. TPH pollution is speculated to be related to oil leakage during the industrial use period and later period of vehicle parking. The results showed that traditional analysis methods can quickly identify the correlation between site pollutants, while SOM + K-means machine learning methods can further effectively extract complex hidden relationships in data and achieve in-depth mining of site monitoring data.
Collapse
Affiliation(s)
- De'an Li
- Guangdong Laboratory of Soil Pollution Fate and Risk Management in Earth's Critical Zone and Guangdong Key Laboratory of Contaminated Environmental Management and Remediation, Guangdong Provincial Academy of Environmental Science, Guangzhou, 510045, China
| | - Yirong Deng
- Guangdong Laboratory of Soil Pollution Fate and Risk Management in Earth's Critical Zone and Guangdong Key Laboratory of Contaminated Environmental Management and Remediation, Guangdong Provincial Academy of Environmental Science, Guangzhou, 510045, China.
| | - LiLi Liu
- Guangdong Laboratory of Soil Pollution Fate and Risk Management in Earth's Critical Zone and Guangdong Key Laboratory of Contaminated Environmental Management and Remediation, Guangdong Provincial Academy of Environmental Science, Guangzhou, 510045, China
| | - Jun Wang
- Guangdong Laboratory of Soil Pollution Fate and Risk Management in Earth's Critical Zone and Guangdong Key Laboratory of Contaminated Environmental Management and Remediation, Guangdong Provincial Academy of Environmental Science, Guangzhou, 510045, China
| | - Zaoquan Huang
- Guangdong Laboratory of Soil Pollution Fate and Risk Management in Earth's Critical Zone and Guangdong Key Laboratory of Contaminated Environmental Management and Remediation, Guangdong Provincial Academy of Environmental Science, Guangzhou, 510045, China
| | - Xiaolu Zhang
- Guangdong Laboratory of Soil Pollution Fate and Risk Management in Earth's Critical Zone and Guangdong Key Laboratory of Contaminated Environmental Management and Remediation, Guangdong Provincial Academy of Environmental Science, Guangzhou, 510045, China
| |
Collapse
|
3
|
Meng X, Zheng J, Wang F, Zheng J, Yang D. Dietary fiber chemical structure determined gut microbiota dynamics. IMETA 2022; 1:e64. [PMID: 38867894 PMCID: PMC10989905 DOI: 10.1002/imt2.64] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 10/13/2022] [Accepted: 11/06/2022] [Indexed: 06/14/2024]
Abstract
Precision modulation of gut microbiota requires elucidation of the relation between dietary fiber intake and gut microbe dynamics. However, current studies on this aspect are few due to many technical limitations. Here, we used Caenorhabditis elegans to minimize the complicated host-microbial factors and to find the relation between dietary fiber chemical structures and gut microbiota dynamics. The Allium schoenoprasum polysaccharide (AssP) structure was elucidated and used as the complex dietary fiber against the simple fiber inulin. In vitro bacterial growth and genome analysis indicated that AssP supports bacterial growth better than inulin, while in vivo gut microbiota analysis of C. elegans fed with AssP showed that microbiota richness increased significantly compared with those fed with inulin. It is concluded that the more complex the dietary fiber chemical structure, the more gut bacteria growth it supports. Together with the community bacterial interactions that alter their abundances in vivo, these factors regulate gut microbiota synergistically.
Collapse
Affiliation(s)
- Xin Meng
- Beijing Key Laboratory of Functional Food from Plant Resources, College of Food Science & Nutritional EngineeringChina Agricultural UniversityBeijingChina
| | - Jun Zheng
- Beijing Key Laboratory of Functional Food from Plant Resources, College of Food Science & Nutritional EngineeringChina Agricultural UniversityBeijingChina
| | - Fengqiao Wang
- Beijing Key Laboratory of Functional Food from Plant Resources, College of Food Science & Nutritional EngineeringChina Agricultural UniversityBeijingChina
| | - Jie Zheng
- Center for Food Safety and Applied NutritionU.S. Food and Drug AdministrationCollege ParkMarylandUSA
| | - Dong Yang
- Beijing Key Laboratory of Functional Food from Plant Resources, College of Food Science & Nutritional EngineeringChina Agricultural UniversityBeijingChina
| |
Collapse
|
4
|
Geng A, Jin M, Li N, Tu Z, Zhu D, Xie R, Wang Q, Sun J. Arabinan hydrolysis by GH43 enzymes of Hungateiclostridium clariflavum and the potential synergistic mechanisms. Appl Microbiol Biotechnol 2022; 106:7793-7803. [PMID: 36251023 DOI: 10.1007/s00253-022-12238-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Revised: 09/30/2022] [Accepted: 10/03/2022] [Indexed: 11/26/2022]
Abstract
Glycoside hydrolase family 43 (GH43) represents a major source of arabinan- and arabinoxylan-active enzymes. Interestingly, some microbes remarkably enriched GH genes of this family, with the reason unknown. Hungateiclostridium clariflavum DSM 19,732 is an efficient lignocellulose degrader, which harbors up to 7 GH43 genes in its genome. We cloned three of the seven GH43 genes, and found that Abn43A is a unique endoarabinanase, which unprecedently showed approximately two times larger activity on sugar beet arabinan (116.8 U/mg) than that on linear arabinan, and it is efficient in arabinooligosaccharide production. Abn43B is an exoarabinanase which directly releases arabinose from linear arabinan. Abn43C is an α-L-arabinofuranosidase which is capable of splitting the arabinose side-chains from arabinooligosaccharides, arabinoxylooligosaccharides, and arabinoxylan. Most importantly, the three GH43 enzymes synergized in hydrolyzing arabinan. Compared to Abn43B alone, a supplement of Abn43A increased the arabinose production from linear arabinan by 150%, reaching 0.44 g/g arabinan. Moreover, an addition of Abn43C to Abn43A and Abn43B boosted the arabinose production from sugar beet arabinan by 15 times, reaching 0.262 g/g arabinan. Our work suggested the intensified functions of multiple GH43 enzymes toward arabinan degradation in H. clariflavum, and a potential synergetic mechanism among the three GH43 enzymes is suggested. KEY POINTS: • Endoarabinanase GH43A prefers branched substrate to linear one • Exoarabinanase GH43B can directly release arabinose from linear arabinan • The three GH43 enzymes synergized in arabinan hydrolysis.
Collapse
Affiliation(s)
- Alei Geng
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China.
| | - Meng Jin
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Nana Li
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Zhuowei Tu
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Daochen Zhu
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Rongrong Xie
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Qianqian Wang
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Jianzhong Sun
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China.
| |
Collapse
|
5
|
Sardar P, Šustr V, Chroňáková A, Lorenc F. Metatranscriptomic holobiont analysis of carbohydrate-active enzymes in the millipede Telodeinopus aoutii (Diplopoda, Spirostreptida). Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.931986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
As important decomposers of soil organic matter, millipedes contribute to lignocellulose decomposition and nutrient cycling. The degradation of lignocellulose requires the action of several carbohydrate-active enzymes (CAZymes) and, in most invertebrates, depends on the activity of mutualistic gut microorganisms. To address the question of the importance of the microbiota and endogenous (host) enzymes in digestive processes in millipedes, we analyzed metatranscriptomic data from the tropical millipede Telodeinopus aoutii at the holobiont level. Functional annotation included identification of expressed CAZymes (CAZy families and EC terms) in the host and its intestinal microbiota, foregut, midgut, and hindgut, compared to non-intestinal tissues. Most of the 175 CAZy families were expressed exclusively in the gut microbiota and more than 50% of these microbial families were expressed exclusively in the hindgut. The greatest diversity of expressed endogenous CAZymes from all gut sections was found in the midgut (77 families). Bacteria were the major microbial producers of CAZymes, Proteobacteria dominating in the midgut and Bacteriodetes with Firmicutes in the hindgut. The contribution of the eukaryotic microbiota to CAZymes production was negligible. Functional classification of expressed CAZy families confirmed a broad functional spectrum of CAZymes potentially expressed in the holobiont. Degradation of lignocellulose in the digestive tract of the millipede T. aoutii depends largely on bacterial enzymes expressed in the hindgut. Endogenous cellulases were not detected, except for the potentially cellulolytic family AA15, but an expression of cellulolytic enzymes of this family was not confirmed at the EC-number level. The midgut had the greatest diversity of expressed endogenous CAZymes, mainly amylases, indicating the importance of digesting α-glucosidases for the millipede. In contrast, bacterial lignocellulolytic enzymes are sparsely expressed here. The hindgut was the hotspot of microbial degradation of cellulose and hemicellulases. The gain of the millipede from the microbial lignocellulose degradation in the gut, and consequently the mutualistic status of the relationship between the millipede and its cellulolytic gut bacteria, depends on the ability of the millipede to take up microbial metabolites as nutrients through the hindgut wall. Enzymes expressed in the intestine can degrade all components of lignocellulose except lignin. Assuming that soil microbiota is partially degraded lignin in the millipede diet, T. aoutii can be considered a decomposer of soil organic matter relying primarily on its gut bacteria. The deposition of millipede fecal pellets containing an organic matter modified by the hindgut bacterial community could be of ecological significance.
Collapse
|
6
|
Abstract
This study evaluated the effects of selenium yeast (SY) on rumen fermentation parameters, rumen bacterial diversity, and expression pathways in goats. A total of 18 Qianbei-pockmarked weather goats from Guizhou (body weight, 25.75 ± 1.75 kg; mean ± standard deviation) were assigned to three groups according to a completely randomized design. Control group (CON, n = 6) kids were fed a basal diet, while treatment 1 (LS, n = 6) and treatment 2 (HS, n = 6) kids were fed a basal diet with 2.4 and 4.8 mg/kg SY, respectively. The feeding trial lasted for 74 days. The results indicated that the ruminal fluid of LS goats had significantly higher levels of propionic, caproic, isobutyric, and isovaleric acids than that of the CON. The levels of butyric and valeric acids were higher in the HS group than in the CON. The acetate:propionate ratio was significantly higher in the CON than in the two treatments. In addition, the inclusion of 2.4 mg/kg SY can lead to a significant decrease in the relative abundances of Euryarchaeota, and Proteobacteria at the phylum level compared to the CON and the HS groups. At the genus level, the LS group had a significant decrease in the relative abundance of Methanobrevibacter and Sarcina, whereas it could lead to a significant increase in the relative abundance of Clostridium in the ruminal fluid relative of the other two groups. At the species level, the LS group had a significant decrease in the relative abundance of bacterium_P3, bacterium_P201, and Sarcina_sp._DSM_11001 compared to the other groups. Moreover, the CON group had a significant decrease in the relative abundance of bacterium_P201 compared to the other two treatments. Compared to the CON, the addition of 2.4 mg/kg SY significantly enriched carbohydrate metabolism pathways in the ruminal fluid for gene encoding. Additionally, goats receiving SY showed a significant upregulation of glycosyl transferase and carbohydrate binding module pathways. These results suggest that dietary supplementation with SY modulates fermentation parameters, and it affects microbial diversity and microbial metagenome in the rumen of Qianbei-pockmarked goats.
Collapse
|
7
|
Deng Y, Debognies A, Zhang Q, Zhang Z, Zhou Z, Zhang J, Sun L, Lu T, Qian H. Effects of ofloxacin on the structure and function of freshwater microbial communities. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2022; 244:106084. [PMID: 35078055 DOI: 10.1016/j.aquatox.2022.106084] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 01/17/2022] [Accepted: 01/18/2022] [Indexed: 06/14/2023]
Abstract
Ofloxacin (OFL) is a broad-spectrum fluoroquinolone antibiotic frequently used in clinic for treating bacterial infections. The discharged OFL would inevitably enter into aquatic ecosystems, affecting the growth of non-target microorganisms, which may result in micro-ecosystem imbalance. To the best of our knowledge, researches in this area are rather sparse. The present study evaluated the response of photosynthetic microorganisms (cyanobacteria, eukaryotic algae) and aquatic microbial community to OFL in a microcosm. Results showed that ofloxacin presented an inhibitory effect on the growth Microcystis aeruginosa. Although 0.1 mg/L OFL has no significant impact on alpha diversity of the microbial communities, it obviously altered the structure and decreased the species interaction of prokaryotic community by reducing the capacities of nitrogen fixation, photosynthetic and metabolic capacity of the microbial community. This study pointed out that the residual OFL in water would disturb the balance of the aquatic micro-ecology, suggesting that more attentions should be given to the negative effects of antibiotics and other bioactive pollutants on aquatic environments.
Collapse
Affiliation(s)
- Yu Deng
- College of Environment, Zhejiang University of technology, Hangzhou 310032, P.R. China
| | - Andries Debognies
- Faculty of Bioscience Engineering, Ghent University Campus Kortrijk, Graaf Karel de Goedelaan 5, 8500 Kortrijk, Belgium
| | - Qi Zhang
- College of Environment, Zhejiang University of technology, Hangzhou 310032, P.R. China
| | - Zhenyan Zhang
- College of Environment, Zhejiang University of technology, Hangzhou 310032, P.R. China
| | - Zhigao Zhou
- College of Environment, Zhejiang University of technology, Hangzhou 310032, P.R. China
| | - Jinfeng Zhang
- College of Environment, Zhejiang University of technology, Hangzhou 310032, P.R. China
| | - Liwei Sun
- College of Environment, Zhejiang University of technology, Hangzhou 310032, P.R. China
| | - Tao Lu
- College of Environment, Zhejiang University of technology, Hangzhou 310032, P.R. China.
| | - Haifeng Qian
- College of Environment, Zhejiang University of technology, Hangzhou 310032, P.R. China
| |
Collapse
|