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Shen H, Yang M, Wang J, Zou X, Tong D, Zhang Y, Tang L, Sun H, Yang L. Dose-dependent joint resistance action of antibacterial mixtures in their hormetic effects on bacterial resistance based on concentration addition model. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 861:160574. [PMID: 36455746 DOI: 10.1016/j.scitotenv.2022.160574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 11/21/2022] [Accepted: 11/25/2022] [Indexed: 06/17/2023]
Abstract
The judgment of joint resistance action is significant for evaluating the resistance risk of antibacterial mixture. Using bacterial mutation frequency (MF) and conjugative transfer frequency (CTF) to respectively characterize the bacterial endogenous and exogenous resistance, mutation unit and conjugative transfer unit have been proposed to judge the joint resistance action of antibacterial mixture at a certain dose. However, these methods could not evaluate the antibacterial mixture's joint resistance action at a larger concentration-range. In this study, the concentration addition for bacterial resistance (CA-BR) approach was used to judge the joint resistance actions between kanamycin sulfate (KAN) and some other typical antibacterial agents, including sulfonamides (SAs), sulfonamide potentiators (SAPs), and silver antibacterial compounds (SACs). Through comparing the hormetic dose-response curves of the binary mixtures on the MF (or CTF) in Escherichia coli (E. coli) and the corresponding CA-BR curves calculated from the hormetic dose-responses of the single agents, the joint resistance actions between KAN and other agents were judged to exhibit dose-dependent feature: with the increase of mixture concentration, the joint mutation actions between KAN and SAs (or SAPs) were fixed at synergism, and the joint mutation actions between KAN and SACs varied from antagonism to synergism; the joint conjugative transfer actions between KAN and other agents changed from antagonism to synergism. Mechanistic explanation suggested that the heterogeneous pattern of joint resistance action had a close relationship with the interplays among the agents' modes of action, and meanwhile was significantly influenced by their joint survival pressure on E. coli. This study reveals the dose-dependent feature for the joint resistance action of antibacterial mixture and highlights the importance of exposure concentration, which will benefit clarifying the resistance risk of antibacterial mixture in the environment.
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Affiliation(s)
- Hongyan Shen
- School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China
| | - Mingru Yang
- School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China
| | - Jing Wang
- School of Environmental and Material Engineering, Yantai University, Yantai 264005, China
| | - Xiaoming Zou
- School of Life Science, Jinggangshan University, Ji'an 343009, China
| | - Danqing Tong
- Key Laboratory of Organic Compound Pollution Control Engineering (MOE), School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Yulian Zhang
- Key Laboratory of Organic Compound Pollution Control Engineering (MOE), School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Liang Tang
- Key Laboratory of Organic Compound Pollution Control Engineering (MOE), School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Haoyu Sun
- Key Laboratory of Organic Compound Pollution Control Engineering (MOE), School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China.
| | - Lei Yang
- Hebei Chemical & Pharmaceutical College, Shijiazhuang 050026, China
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2
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Du YH, Wang MY, Yang LH, Tong LL, Guo DS, Ji XJ. Optimization and Scale-Up of Fermentation Processes Driven by Models. Bioengineering (Basel) 2022; 9:bioengineering9090473. [PMID: 36135019 PMCID: PMC9495923 DOI: 10.3390/bioengineering9090473] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 09/05/2022] [Accepted: 09/09/2022] [Indexed: 11/16/2022] Open
Abstract
In the era of sustainable development, the use of cell factories to produce various compounds by fermentation has attracted extensive attention; however, industrial fermentation requires not only efficient production strains, but also suitable extracellular conditions and medium components, as well as scaling-up. In this regard, the use of biological models has received much attention, and this review will provide guidance for the rapid selection of biological models. This paper first introduces two mechanistic modeling methods, kinetic modeling and constraint-based modeling (CBM), and generalizes their applications in practice. Next, we review data-driven modeling based on machine learning (ML), and highlight the application scope of different learning algorithms. The combined use of ML and CBM for constructing hybrid models is further discussed. At the end, we also discuss the recent strategies for predicting bioreactor scale-up and culture behavior through a combination of biological models and computational fluid dynamics (CFD) models.
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Affiliation(s)
- Yuan-Hang Du
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China
| | - Min-Yu Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Lin-Hui Yang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China
| | - Ling-Ling Tong
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China
| | - Dong-Sheng Guo
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China
- Correspondence: (D.-S.G.); (X.-J.J.)
| | - Xiao-Jun Ji
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, China
- Correspondence: (D.-S.G.); (X.-J.J.)
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3
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Guard J. Through the Looking Glass: Genome, Phenome, and Interactome of Salmonella enterica. Pathogens 2022; 11:pathogens11050581. [PMID: 35631102 PMCID: PMC9144603 DOI: 10.3390/pathogens11050581] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 05/10/2022] [Accepted: 05/11/2022] [Indexed: 11/16/2022] Open
Abstract
This review revisits previous concepts on biological phenomenon contributing to the success of the Salmonella enterica subspecies I as a pathogen and expands upon them to include progress in epidemiology based on whole genome sequencing (WGS). Discussion goes beyond epidemiological uses of WGS to consider how phenotype, which is the biological character of an organism, can be correlated with its genotype to develop a knowledge of the interactome. Deciphering genome interactions with proteins, the impact of metabolic flux, epigenetic modifications, and other complex biochemical processes will lead to new therapeutics, control measures, environmental remediations, and improved design of vaccines.
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Affiliation(s)
- Jean Guard
- U. S. Department of Agriculture, Agricultural Research Service, U. S. National Poultry Research Center, 950 College Station Road, Athens, GA 30605, USA
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4
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The relevance of hormesis at higher levels of biological organization: Hormesis in microorganisms. CURRENT OPINION IN TOXICOLOGY 2022. [DOI: 10.1016/j.cotox.2021.11.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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5
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Tang L, Zhou Y, Zhang Y, Sun H. The role of energy/substrate in microbial hormesis. CURRENT OPINION IN TOXICOLOGY 2022. [DOI: 10.1016/j.cotox.2021.12.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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6
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Agathokleous E, Barceló D, Calabrese EJ. US EPA: Is there room to open a new window for evaluating potential sub-threshold effects and ecological risks? ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 284:117372. [PMID: 34087668 DOI: 10.1016/j.envpol.2021.117372] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 04/08/2021] [Accepted: 05/04/2021] [Indexed: 05/17/2023]
Abstract
With a rule published on 6 January 2021, the US Environmental Protection Agency (EPA) considers for the first time sub-threshold responses, abandoning the use of default dose-response models. This may affect worldwide scientific research, in terms of research design and methodology, and regulatory actions in China and other countries.
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Affiliation(s)
- Evgenios Agathokleous
- Key Laboratory of Agrometeorology of Jiangsu Province, Department of Ecology, School of Applied Meteorology, Nanjing University of Information Science & Technology (NUIST), Nanjing, 210044, China.
| | - Damià Barceló
- Institute of Environmental Assessment and Water Research, IDAEA-CSIC, C/ Jordi Girona 18-26, 08034, Barcelona, Spain; Catalan Institute for Water Research, ICRA-CERCA, Emili Grahit 101, 17003, Girona, Spain
| | - Edward J Calabrese
- Department of Environmental Health Sciences, Morrill I, N344, University of Massachusetts, Amherst, MA, 01003, USA
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Wang S, Huang B, Fan D, Agathokleous E, Guo Y, Zhu Y, Han J. Hormetic responses of soil microbiota to exogenous Cd: A step toward linking community-level hormesis to ecological risk assessment. JOURNAL OF HAZARDOUS MATERIALS 2021; 416:125760. [PMID: 33836329 DOI: 10.1016/j.jhazmat.2021.125760] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 03/09/2021] [Accepted: 03/23/2021] [Indexed: 06/12/2023]
Abstract
We investigated hormetic responses of soil microbial communities to exogenous Cd by assessing microbial count, bacterial and fungal abundance, and microbial community diversity. We found that the bacterial count (BC) decreased (3-40%) by 0.2-40 mg Cdkg-1. Addition of 0.6-2.0 mgkg-1 significantly increased fungal count (FC) by 7-42%, while addition of 4.0-40 mgkg-1 Cd decreased FC by 29-51%, indicating a hormetic dose response. We also found that the FC/BC ratio increased by 0.6-2.0 mg Cdkg-1, with a maximum stimulation of 51%, and decreased (18-27%) by 4.0-40 mg Cdkg-1. Cd had no adverse effect on the α-diversity of bacterial or fungal communities. For relative abundances (RAs) of bacteria and fungi at phylum level, Bacteroidetes RA exhibited a biphasic dose-response curve, with an 18-24% increase at 0.6-4.0 mgkg-1 and a 10% decrease at 40 mgkg-1 compared with control. The results of FC, FC/BC, and Bacteroidetes RAs suggest that hormesis occurred at microbial community level, with positive effects occurring at 0.6-2.0 mgkg-1. This study can contribute to incorporating microbial community hormesis into the ecological risk assessments in the future.
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Affiliation(s)
- Shengyan Wang
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu 210037, China; Co-Innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, Jiangsu 210037, China; National Positioning Observation Station of Hung-tse Lake Wetland Ecosystem in Jiangsu Province, Hongze, Jiangsu 223100, China.
| | - Bin Huang
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu 210037, China.
| | - Diwu Fan
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu 210037, China.
| | - Evgenios Agathokleous
- Key Laboratory of Agrometeorology of Jiangsu Province, Department of Ecology, School of Applied Meteorology, Nanjing University of Information Science & Technology (NUIST), Nanjing 210044, Jiangsu, China.
| | - Yanhui Guo
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu 210037, China.
| | - Yongli Zhu
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu 210037, China; Co-Innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, Jiangsu 210037, China; National Positioning Observation Station of Hung-tse Lake Wetland Ecosystem in Jiangsu Province, Hongze, Jiangsu 223100, China.
| | - Jiangang Han
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu 210037, China; Co-Innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, Jiangsu 210037, China; National Positioning Observation Station of Hung-tse Lake Wetland Ecosystem in Jiangsu Province, Hongze, Jiangsu 223100, China.
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8
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Gao Q, Wang J, Ren L, Cheng Y, Lin Z, Li XG, Sun H. Investigations on the influence of energy source on time-dependent hormesis: A case study of sulfadoxine to Aliivibrio fischeri in different cultivation systems. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 775:145877. [PMID: 33621878 DOI: 10.1016/j.scitotenv.2021.145877] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 02/08/2021] [Accepted: 02/10/2021] [Indexed: 06/12/2023]
Abstract
Hormesis is a biphasic dose-response relationship featured by low-dose stimulation and high-dose inhibition. Although the hormetic phenomenon has been extensively studied over the past decades, there is little information regarding the influence of energy source on the occurrence of hormesis, especially the time-dependent one. In this study, to explore the role of cultivation system's energy source in time-dependent hormesis, the toxic dose-responses of Aliivibrio fischeri (A. fischeri) bioluminescence to Sulfadoxine (SDX) during 24 h were determined in four cultivation systems with different energy source conditions. The results indicated that the time-dependent hormetic effects were induced by SDX in all cultivation systems: SDX triggered hormetic phenomenon on the bioluminescence at each growth stage over 24 h in the cultivation systems with sufficient and insufficient energy source; due to the diauxic growth of A. fischeri under multiple energy source conditions, the hormetic effects of SDX gradually disappeared after the preferred energy source was used up. It was speculated that the inhibitory action of SDX was derived from its interaction with DHPS to impede the synthesis of proteins, and SDX bound with AC to upregulate the quorum sensing (QS) system to exhibit the stimulatory action. Comparing the time-dependent hormesis in each cultivation system, it was obtained that the energy source could impact the hourly maximum stimulatory rate, the EC50 of SDX, and the time point that hormesis occurred, which might result from the influence of energy source on the stimulatory and inhibitory actions of SDX through regulating the metabolic system (individual level) and QS system (group level) of bacteria. This study clarifies the importance of energy source for hormesis occurrence, which may further promote the development of hormesis.
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Affiliation(s)
- Qing Gao
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Jing Wang
- School of Environmental and Material Engineering, Yantai University, Yantai 264005, China
| | - Longfei Ren
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yifei Cheng
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Zhifen Lin
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Key Lab of Chemical Assessment and Sustainability, Shanghai, China
| | - Xin-Gui Li
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Haoyu Sun
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Key Lab of Chemical Assessment and Sustainability, Shanghai, China; Post-doctoral Research Station, College of Civil Engineering, Tongji University, Shanghai 200092, China.
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9
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Fan D, Wang S, Guo Y, Liu J, Agathokleous E, Zhu Y, Han J. The role of bacterial communities in shaping Cd-induced hormesis in 'living' soil as a function of land-use change. JOURNAL OF HAZARDOUS MATERIALS 2021; 409:124996. [PMID: 33444951 DOI: 10.1016/j.jhazmat.2020.124996] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 12/14/2020] [Accepted: 12/26/2020] [Indexed: 06/12/2023]
Abstract
Bacterial communities and soil physicochemical properties shape soil enzymes activities. However, how environmental factors and bacterial communities affect the relationship between increasing doses of soil pollutants and soil alkaline phosphatase (ALP), an index of soil microbiota activity, remains poorly understood. In this study, we investigated the response of soil ALP to 13 doses of Cd (0 and 0.01-100 mg/kg) under four land uses, viz. grassland (GL), natural forest (NF), plantation forest (PF), and wheat field (WF). We found that Cd commonly induced hormetic-like responses of soil ALP, with a maximum stimulation of 10.7%, 10.1%, 11.6%, and 14.5% in GL, NF, PF, and WF, respectively. The size of the hormetic zone (Horzone), an integrated indicator of the stimulation phase and biological plasticity, was in the order GL > WF > PF > NF, and the hormetic zone occurred in the dose range of 5-10, 0.3-10, 0.8-3, and 3-5 mg/kg, respectively. These results indicate highly pleiotropic responses of 'living' soil system to promote resilience to Cd contamination, with soil microbiota potentially contributing to soil ALP's hormetic-like response under different land uses. The hormetic-like response of 'living' soil ALP in different land uses offers a new insight into the identification and minimization of the ecological risks of land-use change in Cd-contaminated lands.
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Affiliation(s)
- Diwu Fan
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
| | - Shengyan Wang
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
| | - Yanhui Guo
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
| | - Jian Liu
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
| | - Evgenios Agathokleous
- Key Laboratory of Agrometeorology of Jiangsu Province, Institute of Ecology, School of Applied Meteorology, Nanjing University of Information Science & Technology (NUIST), Nanjing, Jiangsu 210044, China
| | - Yongli Zhu
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu 210037, China; Co-Innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
| | - Jiangang Han
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu 210037, China; Co-Innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, Jiangsu 210037, China.
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10
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Less Can Be More: The Hormesis Theory of Stress Adaptation in the Global Biosphere and Its Implications. Biomedicines 2021; 9:biomedicines9030293. [PMID: 33805626 PMCID: PMC8000639 DOI: 10.3390/biomedicines9030293] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 03/07/2021] [Accepted: 03/10/2021] [Indexed: 02/07/2023] Open
Abstract
A dose-response relationship to stressors, according to the hormesis theory, is characterized by low-dose stimulation and high-dose inhibition. It is non-linear with a low-dose optimum. Stress responses by cells lead to adapted vitality and fitness. Physical stress can be exerted through heat, radiation, or physical exercise. Chemical stressors include reactive species from oxygen (ROS), nitrogen (RNS), and carbon (RCS), carcinogens, elements, such as lithium (Li) and silicon (Si), and metals, such as silver (Ag), cadmium (Cd), and lead (Pb). Anthropogenic chemicals are agrochemicals (phytotoxins, herbicides), industrial chemicals, and pharmaceuticals. Biochemical stress can be exerted through toxins, medical drugs (e.g., cytostatics, psychopharmaceuticals, non-steroidal inhibitors of inflammation), and through fasting (dietary restriction). Key-lock interactions between enzymes and substrates, antigens and antibodies, antigen-presenting cells, and cognate T cells are the basics of biology, biochemistry, and immunology. Their rules do not obey linear dose-response relationships. The review provides examples of biologic stressors: oncolytic viruses (e.g., immuno-virotherapy of cancer) and hormones (e.g., melatonin, stress hormones). Molecular mechanisms of cellular stress adaptation involve the protein quality control system (PQS) and homeostasis of proteasome, endoplasmic reticulum, and mitochondria. Important components are transcription factors (e.g., Nrf2), micro-RNAs, heat shock proteins, ionic calcium, and enzymes (e.g., glutathion redox enzymes, DNA methyltransferases, and DNA repair enzymes). Cellular growth control, intercellular communication, and resistance to stress from microbial infections involve growth factors, cytokines, chemokines, interferons, and their respective receptors. The effects of hormesis during evolution are multifarious: cell protection and survival, evolutionary flexibility, and epigenetic memory. According to the hormesis theory, this is true for the entire biosphere, e.g., archaia, bacteria, fungi, plants, and the animal kingdoms.
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Fan D, Wang S, Guo Y, Zhu Y, Agathokleous E, Ahmad S, Han J. Cd induced biphasic response in soil alkaline phosphatase and changed soil bacterial community composition: The role of background Cd contamination and time as additional factors. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 757:143771. [PMID: 33229081 DOI: 10.1016/j.scitotenv.2020.143771] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 11/11/2020] [Accepted: 11/12/2020] [Indexed: 06/11/2023]
Abstract
Hormesis is an intriguing phenomenon characterized by low-dose stimulation and high-dose inhibition. The hormetic phenomena have been frequently reported in the past decades, but the researches on the biphasic responses of soil enzymes are still limited. The main objective of this study is to explore dose response of alkaline phosphatase (ALP) to Cd (0, 0.003, 0.03, 0.3, 3.0 and 30 mg/kg) in the presence of different levels of background Cd contamination (bulk soil with no added Cd, BS; low background Cd, LB; medium background Cd, MB; and high background Cd, HB). ALP activity at 0.003-0.3 mg Cd/kg was 13-39% higher than that of the control (0 mg Cd/kg) for HB after 7 d. Similarly, the enzyme activities at 0.003-0.03 mg Cd/kg were 2-25% and 14-17% higher than those of the controls for MB and HB after 60 d. After 90 d, ALP activities at 0.3-3.0 mg Cd/kg increased by 11-17% for LB. The dose-response curves had the shape of an inverted U, showing biphasic responses at days 7 (HB), 60 (MB and HB) and 90 (LB). After 60 days of exposure, total operational taxonomic units (OTU) numbers and unique species exposed to Cd stress displayed hormetic-response curve for MB. The relative abundances of Agrobacterium, Salinimicrobiums, Bacilllus, and Oceanobacillus displayed significantly positive correlations with ALP activity. This suggested that bacterial communities potentially contribute to ALP's hormesis. This study further provides new insights into the ecological mechanisms of pollutant-induced hormesis, and substantially contributes to the ecological risk assessment of Cd pollution.
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Affiliation(s)
- Diwu Fan
- College of Biological and Environment, Nanjing Forestry University, Nanjing, Jiangsu, China.
| | - Shengyan Wang
- College of Biological and Environment, Nanjing Forestry University, Nanjing, Jiangsu, China.
| | - Yanhui Guo
- College of Biological and Environment, Nanjing Forestry University, Nanjing, Jiangsu, China.
| | - Yongli Zhu
- College of Biological and Environment, Nanjing Forestry University, Nanjing, Jiangsu, China; Co-Innovation Center for the Sustainable Forestry in Southern Jiangsu Province, Nanjing, Jiangsu, China; National Positioning Observation Station of Hung-tse Lake Wetland Ecosystem in Jiangsu Province, Nanjing, Jiangsu, China.
| | - Evgenios Agathokleous
- Key Laboratory of Agrometeorology of Jiangsu Province, Institute of Ecology, School of Applied Meteorology, Nanjing University of Information Science & Technology (NUIST), Nanjing, Jiangsu 210044, China.
| | - Sajjad Ahmad
- Department of Civil and Environmental Engineering, University of Nevada, Las Vegas, NV 89154-4015, USA.
| | - Jiangang Han
- College of Biological and Environment, Nanjing Forestry University, Nanjing, Jiangsu, China; Co-Innovation Center for the Sustainable Forestry in Southern Jiangsu Province, Nanjing, Jiangsu, China; National Positioning Observation Station of Hung-tse Lake Wetland Ecosystem in Jiangsu Province, Nanjing, Jiangsu, China.
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