1
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Raab A, Zhang J, Ge Y, Fernández-Mendoza F, Feldmann J. Lipophilic arsenic compounds in the cultured green alga Chlamydomonas reinhardtii. Anal Bioanal Chem 2024; 416:2809-2818. [PMID: 38189919 PMCID: PMC11009773 DOI: 10.1007/s00216-023-05122-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 12/14/2023] [Accepted: 12/22/2023] [Indexed: 01/09/2024]
Abstract
In this study, arsenic (As) speciation was investigated in the freshwater alga Chlamydomonas reinhardtii treated with 20 μg/L arsenate using fractionation as well as ICP-MS/ESI-MS analyses and was compared with the known As metabolite profile of wild-grown Saccharina latissima. While the total As accumulation in C. reinhardtii was about 85% lower than in S. latissima, the relative percentage of arsenolipids was significantly higher in C. reinhardtii (57.0% vs. 5.01%). As-containing hydrocarbons and phospholipids dominated the hydrophobic As profile in S. latissima, but no As-containing hydrocarbons were detectable in C. reinhardtii. Instead for the first time, an arsenoriboside-containing phytol (AsSugPhytol) was found to dominate the hydrophobic arsenicals of C. reinhardtii. Interestingly, this compound and its relatives had so far been only found in green marine microalgae, open sea plankton (mixed assemblage), and sediments but not in brown or red macroalgae. This compound family might therefore relate to differences in the arsenic metabolism between the algae phyla.
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Affiliation(s)
- Andrea Raab
- TESLA - Analytical Chemistry, University of Graz, Universitätsplatz 1, 8010, Graz, Austria.
| | - Jinyu Zhang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, 1 Weigang, Nanjing, China
| | - Ying Ge
- College of Resources and Environmental Sciences, Nanjing Agricultural University, 1 Weigang, Nanjing, China
| | | | - Jörg Feldmann
- TESLA - Analytical Chemistry, University of Graz, Universitätsplatz 1, 8010, Graz, Austria
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2
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Cho CH, Park SI, Huang TY, Lee Y, Ciniglia C, Yadavalli HC, Yang SW, Bhattacharya D, Yoon HS. Genome-wide signatures of adaptation to extreme environments in red algae. Nat Commun 2023; 14:10. [PMID: 36599855 DOI: 10.1038/s41467-022-35566-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Accepted: 12/09/2022] [Indexed: 01/06/2023] Open
Abstract
The high temperature, acidity, and heavy metal-rich environments associated with hot springs have a major impact on biological processes in resident cells. One group of photosynthetic eukaryotes, the Cyanidiophyceae (Rhodophyta), has successfully thrived in hot springs and associated sites worldwide for more than 1 billion years. Here, we analyze chromosome-level assemblies from three representative Cyanidiophyceae species to study environmental adaptation at the genomic level. We find that subtelomeric gene duplication of functional genes and loss of canonical eukaryotic traits played a major role in environmental adaptation, in addition to horizontal gene transfer events. Shared responses to environmental stress exist in Cyanidiales and Galdieriales, however, most of the adaptive genes (e.g., for arsenic detoxification) evolved independently in these lineages. Our results underline the power of local selection to shape eukaryotic genomes that may face vastly different stresses in adjacent, extreme microhabitats.
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Affiliation(s)
- Chung Hyun Cho
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Korea
| | - Seung In Park
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Korea
| | - Tzu-Yen Huang
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Korea
| | - Yongsung Lee
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Korea
| | - Claudia Ciniglia
- Department of Environmental, Biological and Pharmaceutical Science and Technologies, University of Campania Luigi Vanvitelli, Caserta, Italy
| | - Hari Chandana Yadavalli
- Department of Systems Biology, Institute of Life Science and Biotechnology, Yonsei University, Seoul, Korea
| | - Seong Wook Yang
- Department of Systems Biology, Institute of Life Science and Biotechnology, Yonsei University, Seoul, Korea
| | | | - Hwan Su Yoon
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Korea.
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3
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The evolution of plant proton pump regulation via the R domain may have facilitated plant terrestrialization. Commun Biol 2022; 5:1312. [PMID: 36446861 PMCID: PMC9708826 DOI: 10.1038/s42003-022-04291-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 11/23/2022] [Indexed: 11/30/2022] Open
Abstract
Plasma membrane (PM) H+-ATPases are the electrogenic proton pumps that export H+ from plant and fungal cells to acidify the surroundings and generate a membrane potential. Plant PM H+-ATPases are equipped with a C‑terminal autoinhibitory regulatory (R) domain of about 100 amino acid residues, which could not be identified in the PM H+-ATPases of green algae but appeared fully developed in immediate streptophyte algal predecessors of land plants. To explore the physiological significance of this domain, we created in vivo C-terminal truncations of autoinhibited PM H+‑ATPase2 (AHA2), one of the two major isoforms in the land plant Arabidopsis thaliana. As more residues were deleted, the mutant plants became progressively more efficient in proton extrusion, concomitant with increased expansion growth and nutrient uptake. However, as the hyperactivated AHA2 also contributed to stomatal pore opening, which provides an exit pathway for water and an entrance pathway for pests, the mutant plants were more susceptible to biotic and abiotic stresses, pathogen invasion and water loss, respectively. Taken together, our results demonstrate that pump regulation through the R domain is crucial for land plant fitness and by controlling growth and nutrient uptake might have been necessary already for the successful water-to-land transition of plants.
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4
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Hu L, Qian Y, Ci M, Long Y, Zheng H, Xu K, Wang Y. Localized intensification of arsenic methylation within landfill leachate-saturated zone. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 842:156979. [PMID: 35764148 DOI: 10.1016/j.scitotenv.2022.156979] [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: 04/16/2022] [Revised: 06/05/2022] [Accepted: 06/21/2022] [Indexed: 06/15/2023]
Abstract
Leachate-saturated zone (LSZ) of landfills is a complicated biogeochemical hotspot due to the continuous input of electron donors and acceptors from the top refuse layer with leachate migration. In this study, the methylation behavior of the arsenic (As) was investigated. The results indicate that As-methylation processes are influenced by temperature fields in LSZ. The dimethylarsinic acid biotransformation capability can be enhanced with an increase in temperature. Microbial diversity, quantification of functional gene (arsM), and co-occurrence network analysis further characterized the drivers of As methylation in LSZ. As-biogeochemical cycle pathways, as well as As-functional gene distribution among different temperature fields, were modeled on the basis of KEGG annotation. Binning analysis was further employed to assemble As-methylated metagenomes, enabling the identification of novel species for As methylation in landfills. Then, 87 high-quality draft metagenome-assembled genomes (MAGs) were reconstructed from LSZ refuse samples; nearly 15 % (13 of 87) belonged to putative As-methylates functional MAGs. Combined with the model of the As-biogeochemical cycle, nine putative functional species could complete methylation processes alone. The findings of this study highlighted the temperature influence on the As-methylation behavior in LSZ and could facilitate the management of As contamination in landfills.
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Affiliation(s)
- Lifang Hu
- College of Quality and Safety Engineering, Institution of Industrial Carbon Metrology, China Jiliang University, Hangzhou 310018, China
| | - Yating Qian
- College of Quality and Safety Engineering, Institution of Industrial Carbon Metrology, China Jiliang University, Hangzhou 310018, China
| | - Manting Ci
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Instrumental Analysis Center, Zhejiang Gongshang University, Hangzhou 310012, China
| | - Yuyang Long
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Instrumental Analysis Center, Zhejiang Gongshang University, Hangzhou 310012, China.
| | - Haozhe Zheng
- College of Quality and Safety Engineering, Institution of Industrial Carbon Metrology, China Jiliang University, Hangzhou 310018, China
| | - Ke Xu
- College of Quality and Safety Engineering, Institution of Industrial Carbon Metrology, China Jiliang University, Hangzhou 310018, China
| | - Yuqian Wang
- College of Quality and Safety Engineering, Institution of Industrial Carbon Metrology, China Jiliang University, Hangzhou 310018, China
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5
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A comparative study indicates vertical inheritance and horizontal gene transfer of arsenic resistance-related genes in eukaryotes. Mol Phylogenet Evol 2022; 173:107479. [DOI: 10.1016/j.ympev.2022.107479] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 02/10/2022] [Accepted: 04/05/2022] [Indexed: 12/27/2022]
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6
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Schmidt S. Navigating a Two-Way Street: Metal Toxicity and the Human Gut Microbiome. ENVIRONMENTAL HEALTH PERSPECTIVES 2022; 130:32001. [PMID: 35302387 PMCID: PMC8932408 DOI: 10.1289/ehp9731] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 09/07/2021] [Indexed: 05/21/2023]
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7
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Zhang C, Xiao X, Zhao Y, Zhou J, Sun B, Liang Y. Patterns of microbial arsenic detoxification genes in low-arsenic continental paddy soils. ENVIRONMENTAL RESEARCH 2021; 201:111584. [PMID: 34186083 DOI: 10.1016/j.envres.2021.111584] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 05/21/2021] [Accepted: 06/21/2021] [Indexed: 06/13/2023]
Abstract
Microbes mediate the arsenic detoxification in paddy soils, determining the fate of arsenic in soils and its availability to rice plants, yet little is known about the structures and abundances of functional genes as well as the driving forces in low-arsenic paddy fields. To depict the arsenic detoxification functional gene patterns, 429 soil samples were collected from 39 paddy fields across four climatic zones in China, with the arsenic contents ranged from 9.76 to 19.74 mg kg-1. GeoChip, a microarray-based metagenomic technique, was used to analyze the functional genes involved in arsenic detoxification. A total of three arsenic detoxification gene families were detected, aoxB, arxA (arsenite oxidase), and arsM (methyltransferase). Both the diversity and abundance of functional genes varied significantly among sampling sites (p < 0.05) and decreased along the arsenic gradient. Arsenic detoxification genes were carried by bacteria, archaea, and eukaryotes. Redundancy analysis showed that soil samples were grouped according to both climatic zones they located in and arsenic gradients at the continental scale. Soil pH, average annual temperature (AAT), arsenic, annual average precipitation (AAP), and CEC were the most important factors in shaping the functional structure. Structural equation modeling showed that AAT (r = 0.21), pH (r = -0.20), and arsenic contents (r = -0.11) directly affected the arsenic detoxification gene abundances. These findings provide an overall picture of microbial communities involved in arsenic detoxification in paddy soils and reveal the importance of climatic factors in shaping functional genes across a large spatial scale.
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Affiliation(s)
- Chi Zhang
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, China; State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Xian Xiao
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, China.
| | - Yuan Zhao
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, China
| | - Jizhong Zhou
- Institute for Environmental Genomics, Department of Microbiology and Plant Biology, And School of Civil Engineering and Environmental Sciences, University of Oklahoma, Norman, OK, 73019, USA; State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China; Earth and Environmental Sciences, Lawrence Berkeley National Laboratory, Berkeley, CA, 94270, USA
| | - Bo Sun
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Yuting Liang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China.
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8
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Park D, Propper CR, Wang G, Salanga MC. Synonymous single nucleotide polymorphism in arsenic (+3) methyltransferase of the Western mosquitofish (Gambusia affinis) and its gene expression among field populations. ECOTOXICOLOGY (LONDON, ENGLAND) 2021; 30:711-718. [PMID: 33811567 PMCID: PMC8060185 DOI: 10.1007/s10646-021-02376-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/22/2021] [Indexed: 05/05/2023]
Abstract
Naturally occurring arsenic is toxic at extremely low concentrations, yet some species persist even in high arsenic environments. We wanted to test if these species show evidence of evolution associated with arsenic exposure. To do this, we compared allelic variation across 872 coding nucleotides of arsenic (+3) methyltransferase (as3mt) and whole fish as3mt gene expression from three field populations of Gambusia affinis, from water sources containing low (1.9 ppb), medium-low (3.3 ppb), and high (15.7 ppb) levels of arsenic. The high arsenic site exceeds the US EPA's Maximum Contamination Level for drinking water. Medium-low and high populations exhibited homozygosity, and no sequence variation across all animals sampled. Eleven of 24 fish examined (45.8%) in the low arsenic population harbored synonymous single nucleotide polymorphisms (SNPs) in exons 4 and/or 10. SNP presence in the low arsenic population was not associated with differences in as3mt transcript levels compared to fish from the medium-low site, where SNPs were noted; however, as3mt expression in fish from the high arsenic concentration site was significantly lower than the other two sites. Low sequence variation in fish populations from sites with medium-low and high arsenic concentrations suggests greater selective pressure on this allele, while higher variation in the low population suggests a relaxed selection. Our results suggest gene regulation associated with arsenic detoxification may play a more crucial role in influencing responses to arsenic than polymorphic gene sequence. Understanding microevolutionary processes to various contaminants require the evaluation of multiple populations across a wide range of pollution exposures.
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Affiliation(s)
- Daesik Park
- Division of Science Education, Kangwon National University, Chuncheon, Kangwon, 24341, South Korea
| | - Catherine R Propper
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Guangning Wang
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Matthew C Salanga
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, 86011, USA.
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9
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Arsenic methylation - Lessons from three decades of research. Toxicology 2021; 457:152800. [PMID: 33901604 PMCID: PMC10048126 DOI: 10.1016/j.tox.2021.152800] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 04/05/2021] [Accepted: 04/19/2021] [Indexed: 01/26/2023]
Abstract
Between 1990 and 2020, our understanding of the significance of arsenic biomethylation changed in remarkable ways. At the beginning of this period, the conversion of inorganic arsenic into mono- and di-methylated metabolites was viewed primarily as a process that altered the kinetic behavior of arsenic. By increasing the rate of clearance of arsenic, the formation of methylated metabolites reduced exposure to this toxin; that is, methylation was detoxification. By 2020, it was clear that at least some of the toxic effects associated with As exposure depended on formation of methylated metabolites containing trivalent arsenic. Because the trivalent oxidation state of arsenic is associated with increased potency as a cytotoxin and clastogen, these findings were consistent with methylation-related changes in the dynamic behavior of arsenic. That is, methylation was activation. Our current understanding of the role of methylation as a modifier of kinetic and dynamic behaviors of arsenic is the product of research at molecular, cellular, organismic, and population levels. This information provides a basis for refining our estimates of risk associated with long term exposure to inorganic arsenic in environmental media, food, and water. This report summarizes the growth of our knowledge of enzymatically catalyzed methylation of arsenic over this period and considers the prospects for new discoveries.
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10
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Stýblo M, Venkatratnam A, Fry RC, Thomas DJ. Origins, fate, and actions of methylated trivalent metabolites of inorganic arsenic: progress and prospects. Arch Toxicol 2021; 95:1547-1572. [PMID: 33768354 DOI: 10.1007/s00204-021-03028-w] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 03/11/2021] [Indexed: 12/16/2022]
Abstract
The toxic metalloid inorganic arsenic (iAs) is widely distributed in the environment. Chronic exposure to iAs from environmental sources has been linked to a variety of human diseases. Methylation of iAs is the primary pathway for metabolism of iAs. In humans, methylation of iAs is catalyzed by arsenic (+ 3 oxidation state) methyltransferase (AS3MT). Conversion of iAs to mono- and di-methylated species (MAs and DMAs) detoxifies iAs by increasing the rate of whole body clearance of arsenic. Interindividual differences in iAs metabolism play key roles in pathogenesis of and susceptibility to a range of disease outcomes associated with iAs exposure. These adverse health effects are in part associated with the production of methylated trivalent arsenic species, methylarsonous acid (MAsIII) and dimethylarsinous acid (DMAsIII), during AS3MT-catalyzed methylation of iAs. The formation of these metabolites activates iAs to unique forms that cause disease initiation and progression. Taken together, the current evidence suggests that methylation of iAs is a pathway for detoxification and for activation of the metalloid. Beyond this general understanding of the consequences of iAs methylation, many questions remain unanswered. Our knowledge of metabolic targets for MAsIII and DMAsIII in human cells and mechanisms for interactions between these arsenicals and targets is incomplete. Development of novel analytical methods for quantitation of MAsIII and DMAsIII in biological samples promises to address some of these gaps. Here, we summarize current knowledge of the enzymatic basis of MAsIII and DMAsIII formation, the toxic actions of these metabolites, and methods available for their detection and quantification in biomatrices. Major knowledge gaps and future research directions are also discussed.
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Affiliation(s)
- Miroslav Stýblo
- Department of Nutrition, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
| | - Abhishek Venkatratnam
- Department of Nutrition, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
- Department of Environmental Science and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Rebecca C Fry
- Department of Environmental Science and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - David J Thomas
- Chemical Characterization and Exposure Division, Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, 27709, USA.
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11
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Torbøl Pedersen J, De Loma J, Levi M, Palmgren M, Broberg K. Predicted AS3MT Proteins Methylate Arsenic and Support Two Major Phylogenetic AS3MT Groups. Chem Res Toxicol 2020; 33:3041-3047. [PMID: 33156617 PMCID: PMC7759005 DOI: 10.1021/acs.chemrestox.0c00375] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Inorganic
arsenic is one of the most toxic and carcinogenic substances
in the environment, but many organisms, including humans, methylate
inorganic arsenic to mono-, di-, and trimethylated arsenic metabolites,
which the organism can excrete. In humans and other eukaryotic organisms,
the arsenite methyltransferase (AS3MT) protein methylates arsenite.
AS3MT sequences from eukaryotic organisms group phylogenetically with
predicted eubacterial AS3MT sequences, which has led to the suggestion
that AS3MT was acquired from eubacteria by multiple events of horizontal
gene transfer. In this study, we evaluated whether 55 (out of which
47 were predicted based on protein sequence similarity) sequences
encoding putative AS3MT orthologues in 47 species from different kingdoms
can indeed methylate arsenic. Fifty-three of the proteins showed arsenic
methylating capacity. For example, the predicted AS3MT of the human
gut bacterium Faecalibacterium prausnitzii methylated
arsenic efficiently. We performed a kinetic analysis of 14 AS3MT proteins
representing two phylogenetically distinct clades (Group 1 and 2)
that each contain both eubacterial and eukaryotic sequences. We found
that animal and bacterial AS3MTs in Group 1 rarely produce trimethylated
arsenic, whereas Hydra vulgaris and the bacterium Rhodopseudomonas palustris in Group 2 produce trimethylated
arsenic metabolites. These findings suggest that animals during evolution
have acquired different arsenic methylating phenotypes from different
bacteria. Further, it shows that humans carry two bacterial systems
for arsenic methylation: one bacterium-derived AS3MT from Group 1
incorporated in the human genome and one from Group 2 in F.
prausnitzii present in the gut microbiome.
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Affiliation(s)
- Jesper Torbøl Pedersen
- Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen DK-1871, Denmark.,Institute of Environmental Medicine, Karolinska Institutet, Stockholm 171 77, Sweden
| | - Jessica De Loma
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm 171 77, Sweden
| | - Michael Levi
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm 171 77, Sweden
| | - Michael Palmgren
- Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen DK-1871, Denmark
| | - Karin Broberg
- Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen DK-1871, Denmark.,Institute of Environmental Medicine, Karolinska Institutet, Stockholm 171 77, Sweden
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12
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Arsenic Methyltransferase and Methylation of Inorganic Arsenic. Biomolecules 2020; 10:biom10091351. [PMID: 32971865 PMCID: PMC7563989 DOI: 10.3390/biom10091351] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 09/11/2020] [Accepted: 09/18/2020] [Indexed: 12/17/2022] Open
Abstract
Arsenic occurs naturally in the environment, and exists predominantly as inorganic arsenite (As (III) and arsenate As (V)). Arsenic contamination of drinking water has long been recognized as a major global health concern. Arsenic exposure causes changes in skin color and lesions, and more severe health conditions such as black foot disease as well as various cancers originating in the lungs, skin, and bladder. In order to efficiently metabolize and excrete arsenic, it is methylated to monomethylarsonic and dimethylarsinic acid. One single enzyme, arsenic methyltransferase (AS3MT) is responsible for generating both metabolites. AS3MT has been purified from several mammalian and nonmammalian species, and its mRNA sequences were determined from amino acid sequences. With the advent of genome technology, mRNA sequences of AS3MT have been predicted from many species throughout the animal kingdom. Horizontal gene transfer had been postulated for this gene through phylogenetic studies, which suggests the importance of this gene in appropriately handling arsenic exposures in various organisms. An altered ability to methylate arsenic is dependent on specific single nucleotide polymorphisms (SNPs) in AS3MT. Reduced AS3MT activity resulting in poor metabolism of iAs has been shown to reduce expression of the tumor suppressor gene, p16, which is a potential pathway in arsenic carcinogenesis. Arsenic is also known to induce oxidative stress in cells. However, the presence of antioxidant response elements (AREs) in the promoter sequences of AS3MT in several species does not correlate with the ability to methylate arsenic. ARE elements are known to bind NRF2 and induce antioxidant enzymes to combat oxidative stress. NRF2 may be partly responsible for the biotransformation of iAs and the generation of methylated arsenic species via AS3MT. In this article, arsenic metabolism, excretion, and toxicity, a discussion of the AS3MT gene and its evolutionary history, and DNA methylation resulting from arsenic exposure have been reviewed.
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13
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Bhagdikar D, Grundy FJ, Henkin TM. Transcriptional and translational S-box riboswitches differ in ligand-binding properties. J Biol Chem 2020; 295:6849-6860. [PMID: 32209653 DOI: 10.1074/jbc.ra120.012853] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 03/20/2020] [Indexed: 01/27/2023] Open
Abstract
There are a number of riboswitches that utilize the same ligand-binding domain to regulate transcription or translation. S-box (SAM-I) riboswitches, including the riboswitch present in the Bacillus subtilis metI gene, which encodes cystathionine γ-synthase, regulate the expression of genes involved in methionine metabolism in response to SAM, primarily at the level of transcriptional attenuation. A rarer class of S-box riboswitches is predicted to regulate translation initiation. Here we identified and characterized a translational S-box riboswitch in the metI gene from Desulfurispirillum indicum The regulatory mechanisms of riboswitches are influenced by the kinetics of ligand interaction. The half-life of the translational D. indicum metI RNA-SAM complex is significantly shorter than that of the transcriptional B. subtilis metI RNA. This finding suggests that, unlike the transcriptional RNA, the translational metI riboswitch can make multiple reversible regulatory decisions. Comparison of both RNAs revealed that the second internal loop of helix P3 in the transcriptional RNA usually contains an A residue, whereas the translational RNA contains a C residue that is conserved in other S-box RNAs that are predicted to regulate translation. Mutational analysis indicated that the presence of an A or C residue correlates with RNA-SAM complex stability. Biochemical analyses indicate that the internal loop sequence critically determines the stability of the RNA-SAM complex by influencing the flexibility of residues involved in SAM binding and thereby affects the molecular mechanism of riboswitch function.
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Affiliation(s)
- Divyaa Bhagdikar
- Department of Microbiology and Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210
| | - Frank J Grundy
- Department of Microbiology and Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210
| | - Tina M Henkin
- Department of Microbiology and Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210
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14
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Palmgren M, Sørensen DM, Hallström BM, Säll T, Broberg K. Evolution of P2A and P5A ATPases: ancient gene duplications and the red algal connection to green plants revisited. PHYSIOLOGIA PLANTARUM 2020; 168:630-647. [PMID: 31268560 PMCID: PMC7065118 DOI: 10.1111/ppl.13008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/20/2019] [Accepted: 06/27/2019] [Indexed: 05/14/2023]
Abstract
In a search for slowly evolving nuclear genes that may cast light on the deep evolution of plants, we carried out phylogenetic analyses of two well-characterized subfamilies of P-type pumps (P2A and P5A ATPases) from representative branches of the eukaryotic tree of life. Both P-type ATPase genes were duplicated very early in eukaryotic evolution and before the divergence of the present eukaryotic supergroups. Synapomorphies identified in the sequences provide evidence that green plants and red algae are more distantly related than are green plants and eukaryotic supergroups in which secondary or tertiary plastids are common, such as several groups belonging to the clade that includes Stramenopiles, Alveolata, Rhizaria, Cryptophyta and Haptophyta (SAR). We propose that red algae branched off soon after the first photosynthesizing eukaryote had acquired a primary plastid, while in another lineage that led to SAR, the primary plastid was lost but, in some cases, regained as a secondary or tertiary plastid.
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Affiliation(s)
- Michael Palmgren
- Department of Plant and Environmental SciencesUniversity of CopenhagenCopenhagenDenmark
- Institute of Environmental MedicineKarolinska InstitutetStockholmSweden
| | | | - Björn M. Hallström
- Science for Life LaboratoryKTH – Royal Institute of TechnologyStockholmSweden
| | | | - Karin Broberg
- Institute of Environmental MedicineKarolinska InstitutetStockholmSweden
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15
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Apata M, Pfeifer SP. Recent population genomic insights into the genetic basis of arsenic tolerance in humans: the difficulties of identifying positively selected loci in strongly bottlenecked populations. Heredity (Edinb) 2020; 124:253-262. [PMID: 31776483 PMCID: PMC6972707 DOI: 10.1038/s41437-019-0285-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 10/22/2019] [Accepted: 11/13/2019] [Indexed: 02/06/2023] Open
Abstract
Recent advances in genomics have enabled researchers to shed light on the evolutionary processes driving human adaptation, by revealing the genetic architectures underlying traits ranging from lactase persistence, to skin pigmentation, to hypoxic response, to arsenic tolerance. Complicating the identification of targets of positive selection in modern human populations is their complex demographic history, characterized by population bottlenecks and expansions, population structure, migration, and admixture. In particular, founder effects and recent strong population size reductions, such as those experienced by the indigenous peoples of the Americas, have severe impacts on genetic variation that can lead to the accumulation of large allele frequency differences between populations due to genetic drift rather than natural selection. While distinguishing the effects of demographic history from selection remains challenging, neglecting neutral processes can lead to the incorrect identification of candidate loci. We here review the recent population genomic insights into the genetic basis of arsenic tolerance in Andean populations, and utilize this example to highlight both the difficulties pertaining to the identification of local adaptations in strongly bottlenecked populations, as well as the importance of controlling for demographic history in selection scans.
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Affiliation(s)
- Mario Apata
- Center for Evolution & Medicine, School of Life Sciences, Arizona State University, Tempe, AZ, 85821, USA
| | - Susanne P Pfeifer
- Center for Evolution & Medicine, School of Life Sciences, Arizona State University, Tempe, AZ, 85821, USA.
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16
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Pommerrenig B, Diehn TA, Bernhardt N, Bienert MD, Mitani-Ueno N, Fuge J, Bieber A, Spitzer C, Bräutigam A, Ma JF, Chaumont F, Bienert GP. Functional evolution of nodulin 26-like intrinsic proteins: from bacterial arsenic detoxification to plant nutrient transport. THE NEW PHYTOLOGIST 2020; 225:1383-1396. [PMID: 31550387 DOI: 10.1111/nph.16217] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 09/17/2019] [Indexed: 05/18/2023]
Abstract
Nodulin 26-like intrinsic proteins (NIPs) play essential roles in transporting the nutrients silicon and boron in seed plants, but the evolutionary origin of this transport function and the co-permeability to toxic arsenic remains enigmatic. Horizontal gene transfer of a yet uncharacterised bacterial AqpN-aquaporin group was the starting-point for plant NIP evolution. We combined intense sequence, phylogenetic and genetic context analyses and a mutational approach with various transport assays in oocytes and plants to resolve the transorganismal and functional evolution of bacterial and algal and terrestrial plant NIPs and to reveal their molecular transport specificity features. We discovered that aqpN genes are prevalently located in arsenic resistance operons of various prokaryotic phyla. We provided genetic and functional evidence that these proteins contribute to the arsenic detoxification machinery. We identified NIPs with the ancestral bacterial AqpN selectivity filter composition in algae, liverworts, moss, hornworts and ferns and demonstrated that these archetype plant NIPs and their prokaryotic progenitors are almost impermeable to water and silicon but transport arsenic and boron. With a mutational approach, we demonstrated that during evolution, ancestral NIP selectivity shifted to allow subfunctionalisations. Together, our data provided evidence that evolution converted bacterial arsenic efflux channels into essential seed plant nutrient transporters.
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Affiliation(s)
- Benjamin Pommerrenig
- Department of Physiology and Cell Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466, Gatersleben, Germany
- Division of Plant Physiology, University Kaiserslautern, 67663, Kaiserslautern, Germany
| | - Till A Diehn
- Department of Physiology and Cell Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466, Gatersleben, Germany
| | - Nadine Bernhardt
- Genebank Department, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466, Gatersleben, Germany
| | - Manuela D Bienert
- Department of Physiology and Cell Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466, Gatersleben, Germany
| | - Namiki Mitani-Ueno
- Institute of Plant Science and Resources, Okayama University, 710-0046, Kurashiki, Japan
| | - Jacqueline Fuge
- Department of Physiology and Cell Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466, Gatersleben, Germany
| | - Annett Bieber
- Department of Physiology and Cell Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466, Gatersleben, Germany
| | - Christoph Spitzer
- Department of Physiology and Cell Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466, Gatersleben, Germany
| | - Andrea Bräutigam
- Computational Biology, Faculty of Biology, Bielefeld University, 33615, Bielefeld, Germany
| | - Jian Feng Ma
- Institute of Plant Science and Resources, Okayama University, 710-0046, Kurashiki, Japan
| | - François Chaumont
- Louvain Institute of Biomolecular Science and Technology, UC Louvain, 1348, Louvain-la-Neuve, Belgium
| | - Gerd P Bienert
- Department of Physiology and Cell Biology, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466, Gatersleben, Germany
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17
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Hoffmann RD, Olsen LI, Ezike CV, Pedersen JT, Manstretta R, López-Marqués RL, Palmgren M. Roles of plasma membrane proton ATPases AHA2 and AHA7 in normal growth of roots and root hairs in Arabidopsis thaliana. PHYSIOLOGIA PLANTARUM 2019; 166:848-861. [PMID: 30238999 PMCID: PMC7379730 DOI: 10.1111/ppl.12842] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 09/14/2018] [Accepted: 09/17/2018] [Indexed: 05/18/2023]
Abstract
Plasma membrane H+ -ATPase pumps build up the electrochemical H+ gradients that energize most other transport processes into and out of plant cells through channel proteins and secondary active carriers. In Arabidopsis thaliana, the AUTOINHIBITED PLASMA MEMBRANE H+ -ATPases AHA1, AHA2 and AHA7 are predominant in root epidermal cells. In contrast to other H+ -ATPases, we find that AHA7 is autoinhibited by a sequence present in the extracellular loop between transmembrane segments 7 and 8. Autoinhibition of pump activity was regulated by extracellular pH, suggesting negative feedback regulation of AHA7 during establishment of an H+ gradient. Due to genetic redundancy, it has proven difficult to test the role of AHA2 and AHA7, and mutant phenotypes have previously only been observed under nutrient stress conditions. Here, we investigated root and root hair growth under normal conditions in single and double mutants of AHA2 and AHA7. We find that AHA2 drives root cell expansion during growth but that, unexpectedly, restriction of root hair elongation is dependent on AHA2 and AHA7, with each having different roles in this process.
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Affiliation(s)
- Robert D. Hoffmann
- Department of Plant and Environmental SciencesUniversity of CopenhagenDK‐1871FrederiksbergDenmark
| | - Lene I. Olsen
- Department of Plant and Environmental SciencesUniversity of CopenhagenDK‐1871FrederiksbergDenmark
| | - Chukwuebuka V. Ezike
- Department of Plant and Environmental SciencesUniversity of CopenhagenDK‐1871FrederiksbergDenmark
| | - Jesper T. Pedersen
- Department of Plant and Environmental SciencesUniversity of CopenhagenDK‐1871FrederiksbergDenmark
| | - Raffaele Manstretta
- Department of Plant and Environmental SciencesUniversity of CopenhagenDK‐1871FrederiksbergDenmark
| | - Rosa L. López-Marqués
- Department of Plant and Environmental SciencesUniversity of CopenhagenDK‐1871FrederiksbergDenmark
| | - Michael Palmgren
- Department of Plant and Environmental SciencesUniversity of CopenhagenDK‐1871FrederiksbergDenmark
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18
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Palmgren M, Østerberg JT, Nintemann SJ, Poulsen LR, López-Marqués RL. Evolution and a revised nomenclature of P4 ATPases, a eukaryotic family of lipid flippases. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2019; 1861:1135-1151. [DOI: 10.1016/j.bbamem.2019.02.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 02/15/2019] [Accepted: 02/17/2019] [Indexed: 12/15/2022]
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19
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Dunivin TK, Yeh SY, Shade A. A global survey of arsenic-related genes in soil microbiomes. BMC Biol 2019; 17:45. [PMID: 31146755 PMCID: PMC6543643 DOI: 10.1186/s12915-019-0661-5] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 05/02/2019] [Indexed: 01/21/2023] Open
Abstract
Background Environmental resistomes include transferable microbial genes. One important resistome component is resistance to arsenic, a ubiquitous and toxic metalloid that can have negative and chronic consequences for human and animal health. The distribution of arsenic resistance and metabolism genes in the environment is not well understood. However, microbial communities and their resistomes mediate key transformations of arsenic that are expected to impact both biogeochemistry and local toxicity. Results We examined the phylogenetic diversity, genomic location (chromosome or plasmid), and biogeography of arsenic resistance and metabolism genes in 922 soil genomes and 38 metagenomes. To do so, we developed a bioinformatic toolkit that includes BLAST databases, hidden Markov models and resources for gene-targeted assembly of nine arsenic resistance and metabolism genes: acr3, aioA, arsB, arsC (grx), arsC (trx), arsD, arsM, arrA, and arxA. Though arsenic-related genes were common, they were not universally detected, contradicting the common conjecture that all organisms have them. From major clades of arsenic-related genes, we inferred their potential for horizontal and vertical transfer. Different types and proportions of genes were detected across soils, suggesting microbial community composition will, in part, determine local arsenic toxicity and biogeochemistry. While arsenic-related genes were globally distributed, particular sequence variants were highly endemic (e.g., acr3), suggesting dispersal limitation. The gene encoding arsenic methylase arsM was unexpectedly abundant in soil metagenomes (median 48%), suggesting that it plays a prominent role in global arsenic biogeochemistry. Conclusions Our analysis advances understanding of arsenic resistance, metabolism, and biogeochemistry, and our approach provides a roadmap for the ecological investigation of environmental resistomes. Electronic supplementary material The online version of this article (10.1186/s12915-019-0661-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Taylor K Dunivin
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, 48824, USA.,Environmental and Integrative Toxicological Sciences Doctoral Program, Michigan State University, East Lansing, MI, 48824, USA
| | - Susanna Y Yeh
- Institute for Cyber-Enabled Research, Michigan State University, East Lansing, MI, 48824, USA
| | - Ashley Shade
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, 48824, USA. .,Program in Ecology, Evolutionary Biology and Behavior, Michigan State University, East Lansing, MI, 48824, USA. .,Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, USA. .,Plant Resilience Institute, Michigan State University, East Lansing, MI, 48834, USA.
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20
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Li J, Sun Y, Zhang X, Hu Y, Li T, Zhang X, Wang Z, Wu S, Wu Z, Chen B. A methyltransferase gene from arbuscular mycorrhizal fungi involved in arsenic methylation and volatilization. CHEMOSPHERE 2018; 209:392-400. [PMID: 29935468 DOI: 10.1016/j.chemosphere.2018.06.092] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 06/11/2018] [Accepted: 06/12/2018] [Indexed: 05/27/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF), ubiquitous symbiotic fungi associated with the majority of terrestrial plants, were demonstrated to play important roles in arsenic (As) translocation and transformation in the plant-soil continuum, and substantially influence plant As tolerance. However, the direct involvement of AMF in As methylation and volatilization and their molecular mechanisms remain unsolved. Here, an arsenite methyltransferase gene RiMT-11 was identified and characterized from AM fungus Rhizophagus irregularis. Heterologous expression of RiMT-11 enhanced arsenite resistance of E. coli (Δars) through methylating As into monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and ultimately volatile trimethyl arsine (TMAs). In a two-compartment in vitro monoxenic cultivation system, methylated and volatile As were also detected from AM symbioses with arsenate addition, accompanied by strong up-regulation of RiMT-11 expression in extraradical hyphae. The present study provided direct evidence and illustrated an underlying mechanism of As methylation and volatilization by AMF, leading to a deeper insight into the role of AMF in As biogeochemical cycling.
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Affiliation(s)
- Jinglong Li
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuqing Sun
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xin Zhang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Yajun Hu
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan 410125, China
| | - Tao Li
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Xuemeng Zhang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhi Wang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Forestry, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, China
| | - Songlin Wu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Zhaoxiang Wu
- Jiangxi Engineering and Technology Research Center for Ecological Remediation of Heavy Metal Pollution, Institute of Biology and Resources, Jiangxi Academy of Sciences, Nanchang, Jiangxi 330096, China
| | - Baodong Chen
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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21
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Evolutionary Toxicology as a Tool to Assess the Ecotoxicological Risk in Freshwater Ecosystems. WATER 2018. [DOI: 10.3390/w10040490] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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22
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Recurrent horizontal transfer of arsenite methyltransferase genes facilitated adaptation of life to arsenic. Sci Rep 2017; 7:7741. [PMID: 28798375 PMCID: PMC5552862 DOI: 10.1038/s41598-017-08313-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 07/07/2017] [Indexed: 12/12/2022] Open
Abstract
The toxic metalloid arsenic has been environmentally ubiquitous since life first arose nearly four billion years ago and presents a challenge for the survival of all living organisms. Its bioavailability has varied dramatically over the history of life on Earth. As life spread, biogeochemical and climate changes cyclically increased and decreased bioavailable arsenic. To elucidate the history of arsenic adaptation across the tree of life, we reconstructed the phylogeny of the arsM gene that encodes the As(III) S-adenosylmethionine (SAM) methyltransferase. Our results suggest that life successfully moved into arsenic-rich environments in the late Archean Eon and Proterozoic Eon, respectively, by the spread of arsM genes. The arsM genes of bacterial origin have been transferred to other kingdoms of life on at least six occasions, and the resulting domesticated arsM genes promoted adaptation to environmental arsenic. These results allow us to peer into the history of arsenic adaptation of life on our planet and imply that dissemination of genes encoding diverse adaptive functions to toxic chemicals permit adaptation to changes in concentrations of environmental toxins over evolutionary history.
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