1
|
Li M, Shang Z, Ma Y, Zhao H, Ni Z, Wei Z, Zhang X. Tolerance Mechanisms and Removal Efficiency of Chlorella pyrenoidosa in Treating 3-Fluorophenol Pollution. Metabolites 2024; 14:449. [PMID: 39195545 DOI: 10.3390/metabo14080449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2024] [Revised: 08/03/2024] [Accepted: 08/09/2024] [Indexed: 08/29/2024] Open
Abstract
This study investigates the growth tolerance mechanisms of Chlorella pyrenoidosa to 3-fluorophenol and its removal efficiency by algal cells. Our results indicate that C. pyrenoidosa can tolerate up to 100 mg/L of 3-fluorophenol, exhibiting a significant hormesis effect characterized by initial inhibition followed by promotion of growth. In C. pyrenoidosa cells, the activities of superoxide dismutase (SOD) and catalase (CAT), as well as the levels of malondialdehyde (MDA) and reactive oxygen species (ROS), were higher than or comparable to the control group. Metabolic analysis revealed that the 3-fluorophenol treatment activated pathways, such as glycerol phospholipid metabolism, autophagy, glycosylphosphatidylinositol (GPI)-anchored protein biosynthesis, and phenylpropanoid biosynthesis, contributed to the stabilization of cell membrane structures and enhanced cell repair capacity. After 240 h of treatment, over 50% of 3-fluorophenol was removed by algal cells, primarily through adsorption. Thus, C. pyrenoidosa shows potential as an effective biosorbent for the bioremediation of 3-fluorophenol.
Collapse
Affiliation(s)
- Min Li
- School of Biological Science and Engineering, North Minzu University, Yinchuan 750021, China
- Ningxia Key Laboratory of Microbial Resources Development and Applications in Special Environment, Yinchuan 750021, China
| | - Zhenfang Shang
- School of Biological Science and Engineering, North Minzu University, Yinchuan 750021, China
| | - Yonglan Ma
- School of Biological Science and Engineering, North Minzu University, Yinchuan 750021, China
| | - Huijun Zhao
- School of Biological Science and Engineering, North Minzu University, Yinchuan 750021, China
| | - Zhijing Ni
- School of Biological Science and Engineering, North Minzu University, Yinchuan 750021, China
- Ningxia Key Laboratory of Microbial Resources Development and Applications in Special Environment, Yinchuan 750021, China
| | - Zhaojun Wei
- School of Biological Science and Engineering, North Minzu University, Yinchuan 750021, China
| | - Xiu Zhang
- School of Biological Science and Engineering, North Minzu University, Yinchuan 750021, China
- Ningxia Key Laboratory of Microbial Resources Development and Applications in Special Environment, Yinchuan 750021, China
| |
Collapse
|
2
|
Ma G, Wang Q, Ma K, Chen Y, Lu J, Zhang J, Wang X, Wei X, Yu H. Enantioselective metabolism of novel chiral insecticide Paichongding by human cytochrome P450 3A4: A computational insight. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 333:122088. [PMID: 37348694 DOI: 10.1016/j.envpol.2023.122088] [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: 05/24/2023] [Revised: 06/17/2023] [Accepted: 06/19/2023] [Indexed: 06/24/2023]
Abstract
As a novel chiral neonicotinoid insecticide, Paichongding (IPP) has been widely applied in agriculture due to its excellent insecticidal activity. However, the enantioselective metabolism of IPP stereoisomers (5R7R-IPP, 5S7S-IPP, 5R7S-IPP, and 5S7R-IPP) mediated by enzymes in non-target organisms, especially the cytochrome P450s (CYPs), remains unknown. To address this knowledge gap, we developed an integrated computational framework to elucidate the binding interactions and enantioselective metabolism of IPP stereoisomers in human CYP3A4. The results reveal that 5R7R-IPP shows much stronger binding affinity to CYP3A4 than 5S7S-IPP, while enantiomers 5R7S-IPP and 5S7R-IPP have no essential difference in their binding potential, owing to their specific interactions with key CYP3A4 residues. Although enantiomers 5R7R-IPP and 5S7S-IPP feature distinct binding modes resulting from the chiral differences, their transformation activities are slightly different, with C5 and C13 being the primary metabolic sites, respectively. In contrast, CYP3A4 preferably metabolizes 5R7S-IPP over 5S7R-IPP. The metabolism of epimers 5R7R-IPP and 5R7S-IPP share C5-hydroxylation routes due to the conserved 5R-conformaitons, but differ with the transformation routes at C11/C13 and C3 sites. The 7R-chirality of 5S7R-IPP significantly reduces the metabolic potency compared to 5S7S-IPP. CYP3A4-catalyzed hydroxylation and desaturation of IPP stereoisomers generate various chiral metabolites, with C5- and C13-hydroxyIPPs further transforming into depropylated products. Furthermore, the toxicity assessment reveals that IPP, along with the majority of its hydroxylated, desaturated, and depropylated metabolites, can potentially induce adverse effects on human health, specifically hepatotoxicity, respiratory toxicity, and carcinogenicity. This study provides valuable insights into the enantioselective fate of chiral IPP metabolism by CYP3A4, and the identified metabolites can serve as potential biomarkers for monitoring IPP exposure and associated health risk in human body.
Collapse
Affiliation(s)
- Guangcai Ma
- College of Geography and Environmental Sciences, Zhejiang Normal University, Yingbin Avenue 688, 321004, Jinhua, China
| | - Qiuyi Wang
- College of Geography and Environmental Sciences, Zhejiang Normal University, Yingbin Avenue 688, 321004, Jinhua, China
| | - Kan Ma
- College of Geography and Environmental Sciences, Zhejiang Normal University, Yingbin Avenue 688, 321004, Jinhua, China
| | - Yewen Chen
- College of Geography and Environmental Sciences, Zhejiang Normal University, Yingbin Avenue 688, 321004, Jinhua, China
| | - Jiayu Lu
- College of Geography and Environmental Sciences, Zhejiang Normal University, Yingbin Avenue 688, 321004, Jinhua, China
| | - Jing Zhang
- College of Geography and Environmental Sciences, Zhejiang Normal University, Yingbin Avenue 688, 321004, Jinhua, China
| | - Xueyu Wang
- College of Geography and Environmental Sciences, Zhejiang Normal University, Yingbin Avenue 688, 321004, Jinhua, China
| | - Xiaoxuan Wei
- College of Geography and Environmental Sciences, Zhejiang Normal University, Yingbin Avenue 688, 321004, Jinhua, China
| | - Haiying Yu
- College of Geography and Environmental Sciences, Zhejiang Normal University, Yingbin Avenue 688, 321004, Jinhua, China.
| |
Collapse
|
3
|
Kamel EM, Tawfeek AM, El-Bassuony AA, Lamsabhi AM. Mechanistic aspects of reactive metabolite formation in clomethiazole catalyzed biotransformation by cytochrome P450 enzymes. Org Biomol Chem 2023; 21:7158-7172. [PMID: 37609887 DOI: 10.1039/d3ob01014g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Clomethiazole (CLM), a sedative and anticonvulsant drug, is commonly employed for the treatment of alcohol withdrawal syndrome because it suppresses cytochrome P450 (P450) activity associated with the generation of free radicals and liver damage. The catalyzed biotransformation of thiazole-containing drugs by P450 is known to afford reactive metabolites. These metabolites can alter the biological functions of macromolecules and result in toxicity and adverse drug interactions. Multitargeted molecular modeling and quantum chemical DFT calculations were performed to explore the binding modes and molecular mechanisms underlying the mechanism-based inactivation (MBI) of P450 by CLM. The mechanistic details associated with reactive metabolite formation from further metabolic processes were extensively assessed. Seven possible routes were proposed for CLM-P450 biotransformation including CLM hydroxylation, sulfoxidation, N-oxidation, CN epoxidation (oxaziridine formation), and CC epoxidation. The results revealed a degree of preference for the C-N epoxidation pathway because of the low energy requirements of its rate-determining step (8.74 and 10.07 kcal mol-1 for LS and HS states, respectively). A kinetic competition for the CLM-methyl hydroxylation pathway was detected because the H-abstraction energy barrier was relatively comparable to the thermodynamically prevailing oxaziridine formation rate-determining step (12.58 and 14.52 kcal mol-1 for quartet and doublet states, respectively). Our studies assessed the mechanisms of covalent nucleophilic epoxide adduct formation through nucleophilic addition, hydrolysis of epoxidation products, and nonenzymatic degradation. CLM was shown to display P450-inhibitory activity by forming covalent adducts rather than further metabolization to reactive metabolites. The outcomes of molecular docking allowed assessing the binding profile of CLM with three human P450 isozymes, namely, CYP2E1, CYP3A4, and CYP2D6.
Collapse
Affiliation(s)
- Emadeldin M Kamel
- Chemistry Department, Faculty of Science, Beni-Suef University, Beni-Suef 62514, Egypt.
| | - Ahmed M Tawfeek
- Chemistry Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Ashraf A El-Bassuony
- Chemistry Department, Faculty of Science, Beni-Suef University, Beni-Suef 62514, Egypt.
| | - Al Mokhtar Lamsabhi
- Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, Campus de Excelencia UAM-CSIC Cantoblanco, Madrid 28049, Spain
- Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, Madrid 28049, Spain
| |
Collapse
|
4
|
Wang J, Chi Q, Pan L, Zhang R, Mu Y, Shen J. New insights into enhanced biodegradation of 4-bromphenol in a nitrate-reducing system: Process performance and mechanism. WATER RESEARCH 2023; 242:120200. [PMID: 37336182 DOI: 10.1016/j.watres.2023.120200] [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: 05/10/2023] [Revised: 06/06/2023] [Accepted: 06/08/2023] [Indexed: 06/21/2023]
Abstract
Due to the recalcitrant nature of halogenated phenol, conventional anaerobic bioprocess is often limited by low removal efficiency and poor process stability. At the presence of electron acceptors such as nitrate, 4-bromophenol (4-BP) removal efficiency is significantly higher than that in the anaerobic control system, but the mechanism involved is still unclear. Therefore, an up-flow nitrate-reducing bioreactor (NRBR) was designed and consecutively performed for 215 days to explore the synergistic mechanism for BPs biodegradation and nitrate reduction. Complete 4-BP biodegradation could be obtained in NRBR at HRT and 4-BP loading rate of 24 h and 0.29 mol m - 3d - 1, while the TOC removal and nitrate reduction efficiencies were as high as 91.33±2.11% and 98.31±1.33%, respectively. Population evolution analyses revealed that the microorganisms involved in 4-BP debromination and biodegradation (Candidatus Peregrinibacteria, Denitratisoma, Anaerolineaceae and Ignavibacterium) as well as nitrate reduction (Denitratisoma, Anaerolineaceae, Limnobacter and Ignavibacterium) were significantly enriched in NRBR. Major intermediates during 4-BP biodegradation, including 4-bromocatechol, 4‑bromo-6-oxo-hexanoic acid and succinic acid were identified, while a distinct 4-BP biodegradation pathway via hydration, aromatic-ring cleavage, hydrolysis debromination and oxidation was expounded. Metagenomic analysis indicated that oxidation (had, pht4, boh, butA), hydrolysis debromination ((S)-2-haloacid dehalogenase) and bio-mineralization (gabD, sdhA) of 4-BP were largely enhanced in NRBR. Moreover, carbon, nitrogen, energy and amino acid metabolisms were significantly facilitated with the injection of nitrate in order to provide energy and electron, thus enhanced microbial activities and enzymatic reactions in NRBR. The proposed mechanism provides new insights into our mechanistic understanding of halogenated phenol biodegradation and the development of sustainable bioremediation strategies.
Collapse
Affiliation(s)
- Jing Wang
- Key Laboratory of Environmental Remediation and Ecological Health, Ministry of Industry and Information Technology, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Qiang Chi
- Key Laboratory of Environmental Remediation and Ecological Health, Ministry of Industry and Information Technology, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Ling Pan
- Key Laboratory of Environmental Remediation and Ecological Health, Ministry of Industry and Information Technology, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Ranran Zhang
- Key Laboratory of Environmental Remediation and Ecological Health, Ministry of Industry and Information Technology, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Yang Mu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Jinyou Shen
- Key Laboratory of Environmental Remediation and Ecological Health, Ministry of Industry and Information Technology, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
| |
Collapse
|
5
|
Gao Y, Hu X, Deng C, Wang M, Niu X, Luo N, Ji Y, Li G, An T. New insight into molecular mechanism of P450-Catalyzed metabolism of emerging contaminants and its consequence for human health: A case study of preservative methylparaben. ENVIRONMENT INTERNATIONAL 2023; 174:107890. [PMID: 37001212 DOI: 10.1016/j.envint.2023.107890] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 03/13/2023] [Accepted: 03/15/2023] [Indexed: 06/19/2023]
Abstract
Hydroxylated metabolites in the living body are considered as a potential biomarker of exposure to emerging contaminations (ECs) and breast cancer, but their formation mechanism has not received enough attention. Besides, the adverse impacts of metabolites during the metabolic transformation of ECs largely remain unknown. In this study, we employed a density functional calculation combing with in-vitro incubation of human liver microsomes to explore the bio-transformation of preservative methylparaben (MPB) in human bodies. Our results showed that hydroxylated metabolites of MPB (OH-MPB) were observed experimentally, while a formation mechanism was revealed at the molecular level. That is, hydroxylated metabolite was exclusively formed via the hydrogen abstraction from the phenolic hydroxyl group of MPB followed by the OH-rebound pathway, rather than the direct hydroxylation on the benzene ring. The increasing of hydroxyl groups on ECs could improve the metabolisms. This was confirmed in the metabolism of ECs without hydroxyl group and with multiple-hydroxyl groups, respectively. Furthermore, toxicity assessments show that compared to parent MPB, the hydroxylated metabolites have increased negative impacts on the gastrointestinal system and liver. A semiquinone product exhibits potential damage in the cardiovascular system and epoxides are toxic to the blood and gastrointestinal system. The findings deepen our insight into the biotransformation of parabens in human health, especially by providing health warnings about the potential impacts caused by semiquinone and epoxides.
Collapse
Affiliation(s)
- Yanpeng Gao
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Xinyi Hu
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Chuyue Deng
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Mei Wang
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Xiaolin Niu
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Na Luo
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Yuemeng Ji
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China.
| | - Guiying Li
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Taicheng An
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| |
Collapse
|
6
|
Wang L, Hu Z, Hu M, Zhao J, Zhou P, Zhang Y, Zheng X, Zhang Y, Hu ZT, Pan Z. Cometabolic biodegradation system employed subculturing photosynthetic bacteria: A new degradation pathway of 4-chlorophenol in hypersaline wastewater. BIORESOURCE TECHNOLOGY 2022; 361:127670. [PMID: 35878775 DOI: 10.1016/j.biortech.2022.127670] [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: 06/03/2022] [Revised: 07/17/2022] [Accepted: 07/18/2022] [Indexed: 06/15/2023]
Abstract
4-chlorophenol (4-CP) as a toxic persistent pollutant is quite difficult treatment by using traditional biological processes. Herein, photosynthetic bacteria (PSB) driven cometabolic biodegradation system associated with exogeneous carbon sources (e.g., sodium acetate) has been demonstrated as an effective microbial technique. The biodegradation rate (ri) can be at 0.041 d-1 with degradation efficiency of 93% in 3094 lx. Through the study of subculturing PSB in absence of NaCl, it was found that 50% inoculation time can be saved but keeping a similar 4-CP biodegradation efficiency in scale-up salinity system. A new plausible biodegradation pathway for 4-CP in 4th G PSB cometabolic system is proposed based on the detected cyclohexanone generation followed by ring opening. It is probably ascribed to the increasement of Firmicutes and Bacteroidetes at phyla level classified based on microbial community. This study contributes to a new insight into cometabolic technology for chlorophenol treatment in industrial hypersaline wastewater.
Collapse
Affiliation(s)
- Liang Wang
- College of Environment, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou, Zhejiang 310014, PR China
| | - Zhongce Hu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou, Zhejiang 310014, PR China
| | - Mian Hu
- College of Environment, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou, Zhejiang 310014, PR China
| | - Jun Zhao
- Institute of Bioresource and Agriculture, Hong Kong Baptist University, Hong Kong Special Administrative Region
| | - Peijie Zhou
- College of Environment, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou, Zhejiang 310014, PR China
| | - Yongjie Zhang
- College of Environment, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou, Zhejiang 310014, PR China
| | - Xin Zheng
- College of Environment, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou, Zhejiang 310014, PR China
| | - Yifeng Zhang
- Department of Environmental & Resource Engineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Zhong-Ting Hu
- College of Environment, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou, Zhejiang 310014, PR China
| | - Zhiyan Pan
- College of Environment, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou, Zhejiang 310014, PR China.
| |
Collapse
|
7
|
Yadav R, Awasthi N, Kumar D. Biotransformation of BPA via epoxidation catalyzed by Cytochrome P450. INORG CHEM COMMUN 2022. [DOI: 10.1016/j.inoche.2022.109321] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
8
|
Computational Insight into Biotransformation Profiles of Organophosphorus Flame Retardants to Their Diester Metabolites by Cytochrome P450. Molecules 2022; 27:molecules27092799. [PMID: 35566150 PMCID: PMC9102461 DOI: 10.3390/molecules27092799] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 04/24/2022] [Accepted: 04/26/2022] [Indexed: 02/05/2023] Open
Abstract
Biotransformation of organophosphorus flame retardants (OPFRs) mediated by cytochrome P450 enzymes (CYPs) has a potential correlation with their toxicological effects on humans. In this work, we employed five typical OPFRs including tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), tris(1-chloro-2-propyl) phosphate (TCIPP), tri(2-chloroethyl) phosphate (TCEP), triethyl phosphate (TEP), and 2-ethylhexyl diphenyl phosphate (EHDPHP), and performed density functional theory (DFT) calculations to clarify the CYP-catalyzed biotransformation of five OPFRs to their diester metabolites. The DFT results show that the reaction mechanism consists of Cα-hydroxylation and O-dealkylation steps, and the biotransformation activities of five OPFRs may follow the order of TCEP ≈ TEP ≈ EHDPHP > TCIPP > TDCIPP. We further performed molecular dynamics (MD) simulations to unravel the binding interactions of five OPFRs in the CYP3A4 isoform. Binding mode analyses demonstrate that CYP3A4-mediated metabolism of TDCIPP, TCIPP, TCEP, and TEP can produce the diester metabolites, while EHDPHP metabolism may generate para-hydroxyEHDPHP as the primary metabolite. Moreover, the EHDPHP and TDCIPP have higher binding potential to CYP3A4 than TCIPP, TCEP, and TEP. This work reports the biotransformation profiles and binding features of five OPFRs in CYP, which can provide meaningful clues for the further studies of the metabolic fates of OPFRs and toxicological effects associated with the relevant metabolites.
Collapse
|