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Shi HP, Zhao YH, Zheng ML, Gong CY, Yan L, Liu Y, Luo YM, Liu ZP. Arsenic effectively improves the degradation of fluorene by Rhodococcus sp. 2021 under the combined pollution of arsenic and fluorene. CHEMOSPHERE 2024; 353:141635. [PMID: 38447897 DOI: 10.1016/j.chemosphere.2024.141635] [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: 08/08/2023] [Revised: 02/08/2024] [Accepted: 03/01/2024] [Indexed: 03/08/2024]
Abstract
The performance of bacterial strains in executing degradative functions under the coexistence of heavy metals/heavy metal-like elements and organic contaminants is understudied. In this study, we isolated a fluorene-degrading bacterium, highly arsenic-resistant, designated as strain 2021, from contaminated soil at the abandoned site of an old coking plant. It was identified as a member of the genus Rhodococcus sp. strain 2021 exhibited efficient fluorene-degrading ability under optimal conditions of 400 mg/L fluorene, 30 °C, pH 7.0, and 250 mg/L trivalent arsenic. It was noted that the addition of arsenic could promote the growth of strain 2021 and improve the degradation of fluorene - a phenomenon that has not been described yet. The results further indicated that strain 2021 can oxidize As3+ to As5+; here, approximately 13.1% of As3+ was converted to As5+ after aerobic cultivation for 8 days at 30 °C. The addition of arsenic could greatly up-regulate the expression of arsR/A/B/C/D and pcaG/H gene clusters involved in arsenic resistance and aromatic hydrocarbon degradation; it also aided in maintaining the continuously high expression of cstA that codes for carbon starvation protein and prmA/B that codes for monooxygenase. These results suggest that strain 2021 holds great potential for the bioremediation of environments contaminated by a combination of arsenic and polycyclic aromatic hydrocarbons. This study provides new insights into the interactions among microbes, as well as inorganic and organic pollutants.
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Affiliation(s)
- Hong-Peng Shi
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 101408, China
| | - Ying-Hao Zhao
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 101408, China
| | - Mei-Lin Zheng
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 101408, China
| | - Cheng-Yan Gong
- University of Chinese Academy of Sciences, Beijing 101408, China; Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China
| | - Lei Yan
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Ying Liu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yong-Ming Luo
- Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Zhi-Pei Liu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
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Ren XY, Zheng YL, Liu ZL, Duan GL, Zhu D, Ding LJ. Exploring ecological effects of arsenic and cadmium combined exposure on cropland soil: from multilevel organisms to soil functioning by multi-omics coupled with high-throughput quantitative PCR. JOURNAL OF HAZARDOUS MATERIALS 2024; 466:133567. [PMID: 38271874 DOI: 10.1016/j.jhazmat.2024.133567] [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: 10/23/2023] [Revised: 01/12/2024] [Accepted: 01/17/2024] [Indexed: 01/27/2024]
Abstract
Arsenic (As) and cadmium (Cd) pose potential ecological threats to cropland soils; however, few studies have investigated their combined effects on multilevel organisms and soil functioning. Here, we used collembolans and soil microbiota as test organisms to examine their responses to soil As and Cd co-contamination at the gene, individual, and community levels, respectively, and further uncovered ecological relationships between pollutants, multilevel organisms, and soil functioning. At the gene level, collembolan transcriptome revealed that elevated As concentrations stimulated As-detoxifying genes AS3MT and GST, whereas the concurrent Cd restrained GST gene expression. At the individual level, collembolan reproduction was sensitive to pollutants while collembolan survival wasn't. At the community level, significant but inconsistent correlations were observed between the biodiversity of different soil keystone microbial clusters and soil As levels. Moreover, soil functioning related to nutrient (e.g., carbon, nitrogen, phosphorus, and sulfur) cycles was inhibited under As and Cd co-exposure only through the mediation of plant pathogens. Overall, these findings suggested multilevel bioindicators (i.e., AS3MT gene expression in collembolans, collembolan reproduction, and biodiversity of soil keystone microbial clusters) in cropland soils co-contaminated with As and Cd, thus improving the understanding of the ecotoxicological impact of heavy metal co-contamination on soil ecosystems.
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Affiliation(s)
- Xin-Yue Ren
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen 361021, China; University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, China
| | - Yu-Ling Zheng
- 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, 19A Yuquan Road, Beijing 100049, China
| | - Zhe-Lun Liu
- 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, 19A Yuquan Road, Beijing 100049, China
| | - Gui-Lan Duan
- 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, 19A Yuquan Road, Beijing 100049, China
| | - Dong Zhu
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen 361021, China; University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, China; Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control, CAS Haixi Industrial Technology Innovation Center in Beilun, Ningbo 315830, China.
| | - Long-Jun Ding
- 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, 19A Yuquan Road, Beijing 100049, China.
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Sukkasam N, Leksingto J, Incharoensakdi A, Monshupanee T. Chemical Triggering Cyanobacterial Glycogen Accumulation: Methyl Viologen Treatment Increases Synechocystis sp. PCC 6803 Glycogen Storage by Enhancing Levels of Gene Transcript and Substrates in Glycogen Synthesis. PLANT & CELL PHYSIOLOGY 2023; 63:2027-2041. [PMID: 36197756 DOI: 10.1093/pcp/pcac136] [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: 07/12/2022] [Revised: 09/26/2022] [Accepted: 10/03/2022] [Indexed: 06/16/2023]
Abstract
Two-stage cultivation is effective for glycogen production by cyanobacteria. Cells were first grown under adequate nitrate supply (BG11) to increase biomass and subsequently transferred to nitrogen deprivation (-N) to stimulate glycogen accumulation. However, the two-stage method is time-consuming and requires extensive energy. Thus, one-stage cultivation that enables both cell growth and glycogen accumulation is advantageous. Such one-stage method could be achieved using a chemical triggering glycogen storage. However, there is a limited study on such chemicals. Here, nine compounds previously reported to affect cyanobacterial cellular functions were examined in Synechocystis sp. PCC 6803. 2-Phenylethanol, phenoxyethanol, 3-(3,4-dichlorophenyl)-1,1-dimethylurea and methyl viologen can stimulate glycogen accumulation. The oxidative stress agent, methyl viologen significantly increased glycogen levels up to 57% and 69% [w/w dry weight (DW)] under BG11 and -N cultivation, respectively. One-stage cultivation where methyl viologen was directly added to the pre-grown culture enhanced glycogen storage to 53% (w/w DW), compared to the 10% (w/w DW) glycogen level of the control cells without methyl viologen. Methyl viologen treatment reduced the contents of total proteins (including phycobiliproteins) but caused increased transcript levels of glycogen synthetic genes and elevated levels of metabolite substrates for glycogen synthesis. Metabolomic results suggested that upon methyl viologen treatment, proteins degraded to amino acids, some of which could be used as a carbon source for glycogen synthesis. Results of oxygen evolution and metabolomic analysis suggested that photosynthesis and carbon fixation were not completely inhibited upon methyl viologen treatment, and these two processes may partially generate upstream metabolites required for glycogen synthesis.
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Affiliation(s)
- Nannaphat Sukkasam
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
- Program in Biotechnology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Jidapa Leksingto
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Aran Incharoensakdi
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
- Academy of Science, Royal Society of Thailand, Bangkok 10300, Thailand
| | - Tanakarn Monshupanee
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
- Program in Biotechnology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
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Sukkasam N, Incharoensakdi A, Monshupanee T. Chemicals Affecting Cyanobacterial Poly(3-hydroxybutyrate) Accumulation: 2-Phenylethanol Treatment Combined with Nitrogen Deprivation Synergistically Enhanced Poly(3-hydroxybutyrate) Storage in Synechocystis sp. PCC6803 and Anabaena sp. TISTR8076. PLANT & CELL PHYSIOLOGY 2022; 63:1253-1272. [PMID: 35818829 DOI: 10.1093/pcp/pcac100] [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: 02/06/2022] [Revised: 07/04/2022] [Accepted: 07/11/2022] [Indexed: 06/15/2023]
Abstract
Various photoautotrophic cyanobacteria increase the accumulation of bioplastic poly(3-hydroxybutyrate) (PHB) under nitrogen deprivation (-N) for energy storage. Several metabolic engineering enhanced cyanobacterial PHB accumulation, but these strategies are not applicable in non-gene-transformable strains. Alternatively, stimulating PHB levels by chemical exposure is desirable because it might be applied to various cyanobacterial strains. However, the study of such chemicals is still limited. Here, 19 compounds previously reported to affect bacterial cellular processes were evaluated for their effect on PHB accumulation in Synechocystis sp. PCC6803, where 3-(3,4-dichlorophenyl)-1,1-dimethylurea, methyl viologen, arsenite, phenoxyethanol and 2-phenylethanol were found to increase PHB accumulation. When cultivated with optimal nitrate supply, Synechocystis contained less than 0.5% [w/w dry weight (DW)] PHB, while cultivation under -N conditions increased the PHB content to 7% (w/w DW). Interestingly, the -N cultivation combined with 2-phenylethanol exposure reduced the Synechocystis protein content by 27% (w/w DW) but significantly increased PHB levels up to 33% (w/w DW), the highest ever reported photoautotrophic cyanobacterial PHB accumulation in a wild-type strain. Results from transcriptomic and metabolomic analysis suggested that under 2-phenylethanol treatment, Synechocystis proteins were degraded to amino acids, which might be subsequently utilized as the source of carbon and energy for PHB biosynthesis. 2-Phenylethanol treatment also increased the levels of metabolites required for Synechocystis PHB synthesis (acetyl-CoA, acetoacetyl-CoA, 3-hydroxybutyryl-CoA and NADPH). Additionally, under -N, the exposure to phenoxyethanol and 2-phenylethanol increased the PHB levels of Anabaena sp. from 0.4% to 4.1% and 6.6% (w/w DW), respectively. The chemicals identified in this study might be applicable for enhancing PHB accumulation in other cyanobacteria.
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Affiliation(s)
- Nannaphat Sukkasam
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
- Program in Biotechnology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Aran Incharoensakdi
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
- Academy of Science, Royal Society of Thailand, Bangkok 10300, Thailand
| | - Tanakarn Monshupanee
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
- Program in Biotechnology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
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Mao Q, Xie Z, Irshad S, Zhong Z, Liu T, Pei F, Gao B, Li L. Effect of arsenic accumulation on growth and antioxidant defense system of Chlorella thermophila SM01 and Leptolyngbya sp. XZMQ. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Chakdar H, Thapa S, Srivastava A, Shukla P. Genomic and proteomic insights into the heavy metal bioremediation by cyanobacteria. JOURNAL OF HAZARDOUS MATERIALS 2022; 424:127609. [PMID: 34772552 DOI: 10.1016/j.jhazmat.2021.127609] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 10/16/2021] [Accepted: 10/24/2021] [Indexed: 06/13/2023]
Abstract
Heavy metals (HMs) pose a global ecological threat due to their toxic effects on aquatic and terrestrial life. Effective remediation of HMs from the environment can help to restore soil's fertility and ecological vigor, one of the key Sustainable Development Goals (SDG) set by the United Nations. The cyanobacteria have emerged as a potential option for bioremediation of HMs due to their unique adaptations and robust metabolic machineries. Generally, cyanobacteria deploy multifarious mechanisms such as biosorption, bioaccumulation, activation of metal transporters, biotransformation and induction of detoxifying enzymes to sequester and minimize the toxic effects of heavy metals. Therefore, understanding the physiological responses and regulation of adaptation mechanisms at molecular level is necessary to unravel the candidate genes and proteins which can be manipulated to improve the bioremediation efficiency of cyanobacteria. Chaperons, cellular metabolites (extracellular polymers, biosurfactants), transcriptional regulators, metal transporters, phytochelatins and metallothioneins are some of the potential targets for strain engineering. In the present review, we have discussed the potential of cyanobacteria for HM bioremediation and provided a deeper insight into their genomic and proteomic regulation of various tolerance mechanisms. These approaches might pave new possibilities of implementing genetic engineering strategies for improving bioremediation efficiency with a future perspective.
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Affiliation(s)
- Hillol Chakdar
- Microbial Technology Unit II, ICAR-National Bureau of Agriculturally Important Microorganisms (NBAIM), Mau 275103, Uttar Pradesh, India
| | - Shobit Thapa
- Microbial Technology Unit II, ICAR-National Bureau of Agriculturally Important Microorganisms (NBAIM), Mau 275103, Uttar Pradesh, India
| | - Amit Srivastava
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, ID 47907-2048, United States
| | - Pratyoosh Shukla
- School of Biotechnology, Institute of Science, Banaras Hindu University, Varanasi 221005, Uttar Pradesh, India; Enzyme Technology and Protein Bioinformatics Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak 124001, Haryana, India.
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Ghosh A, Bhadury P. Genome description of Nostoc ellipsosporum strain NOK (Nostocales, Cyanobacteria) isolated from an arsenic contaminated paddy field of the Bengal Delta Plains. IOP SCINOTES 2021. [DOI: 10.1088/2633-1357/ac202f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
A diazotrophic cyanobacterium, Nostoc ellipsosporum strain NOK, was isolated from an arsenic contaminated paddy field of the Bengal Delta Plains (BDP). Located across India and Bangladesh, BDP, is one of the worst arsenic (As)-affected regions of the world. Previous studies have shown this isolate to be tolerant to high concentration of arsenic (≦400 μM). The genome of this isolate was sequenced to identify the genes involved in various metabolic pathways including arsenic resistance and biofilm formation. Whole genome analyses showed Nostoc ellipsosporum strain NOK to be closely related to N. punctiforme strain PCC73102. The genome is about 10.9 Mbp which assembled into 694 contigs. Genome annotation identified 10120 genes out of which 10000 were CDSs. There are a total of 9927 protein coding genes in addition to 120 RNA coding genes. The genome codes three 5S rRNA, four 16S rRNA and three 23S rRNA genes along with 103 tRNAs, 7 ncRNAs and 73 pseudo-genes. The G + C% of the genome is 54.28. The genome codes for crucial genes involved in biofilm formation in response to stress conditions including arsenic stress. The arsBHC operon is present within the genome which makes this tolerant to high concentration of arsenic which might lead to biofilm formation. A number of ABC transporters including cysUW and sbp (sulfate/thiosulfate), nrtABC (nitrate/nitrite/cyanate), cmpABCD (bicarbonate), ssuABC (alkane sulfonate), modABCF (molybdate; 2 copies), afuAC (iron), pstA (phosphate; 2 copies), pstBC, pstS (4 copies), cbiOQ (cobalt and nickel) and opuBC, opuBB and opuBA (osmoprotectants) were identified.
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Patel A, Tiwari S, Prasad SM. Effect of Time Interval on Arsenic Toxicity to Paddy Field Cyanobacteria as Evident by Nitrogen Metabolism, Biochemical Constituent, and Exopolysaccharide Content. Biol Trace Elem Res 2021; 199:2031-2046. [PMID: 32767030 DOI: 10.1007/s12011-020-02289-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 07/13/2020] [Indexed: 10/23/2022]
Abstract
Arsenic poisoning in aquatic ecosystem is a global concern that obstructs the productivity of agricultural lands (paddy fields) by targeting the growth of cyanobacteria. The cyanobacteria also tolerate and accumulate elevated concentration of arsenic (As) inside the cell and excrete out from cells in less toxic forms after the successive time interval. Thus to validate this, the study was carried out at two different time intervals, i.e., 48 h and 96 h. Two redox forms of As arsenate (AsV) and arsenite (AsIII) at different concentrations (50, 100, and 150 mM AsV; 50, 100, and 150 μM AsIII) caused substantial reduction in growth, pigments (Chl a/Car and phycobiliproteins: phycocyanin, allophycocyanin, and phycoerythrin), inorganic nitrogen ( nitrate (NO3-) and nitrite (NO2-)) uptake, activity of enzymes (NR, NiR, GS, and GOGAT) of nitrogen metabolism, biochemical constituents (protein, carbohydrate, and exopolysaccharide (EPS) contents of Nostoc muscorum, and Anabaena sp. PCC7120. The tested doses of AsV and AsIII after 48 h of exposure exhibited adverse impact on these parameters, but after 96 h with lower doses of AsV (50 mM and 100 mM) and AsIII (50 μM and 100 μM), significant recovery was recorded. Contrary to this, at higher dose of AsV (150 mM) and AsIII (150 μM), the adverse impact was further aggravated with increasing time exposure. Contrary to the activity of NR, NiR, GS, and GOGAT, GDH activity (alternative NH3+ assimilating enzyme) was found to increase, and after 96 h, the activity showed declining trend but still higher than the control. The biochemical constituent EPS (first protective barrier) under scanning electron microscope showed more accumulation of dry adsorbent in the case of AsIII stress hence displayed more toxic nature of AsIII than AsV. The study concludes that with increasing time exposure, the recovery in growth and related parameters mainly at lower doses of AsV and AsIII points toward adaptability of cyanobacteria which was more pronounced in Nostoc muscorum.
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Affiliation(s)
- Anuradha Patel
- Ranjan Plant Physiology and Biochemistry Laboratory, Department of Botany, University of Allahabad, Prayagraj, 211002, India
| | - Sanjesh Tiwari
- Ranjan Plant Physiology and Biochemistry Laboratory, Department of Botany, University of Allahabad, Prayagraj, 211002, India
| | - Sheo Mohan Prasad
- Ranjan Plant Physiology and Biochemistry Laboratory, Department of Botany, University of Allahabad, Prayagraj, 211002, India.
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Arsenate-Induced Changes in Bacterial Metabolite and Lipid Pools during Phosphate Stress. Appl Environ Microbiol 2021; 87:AEM.02261-20. [PMID: 33361371 DOI: 10.1128/aem.02261-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 12/06/2020] [Indexed: 11/20/2022] Open
Abstract
Agrobacterium tumefaciens GW4 is a heterotrophic arsenite-oxidizing bacterium with a high resistance to arsenic toxicity. It is now a model organism for studying the processes of arsenic detoxification and utilization. Previously, we demonstrated that under low-phosphate conditions, arsenate [As(V)] could enhance bacterial growth and be incorporated into biomolecules, including lipids. While the basic microbial As(V) resistance mechanisms have been characterized, global metabolic responses under low phosphate remain largely unknown. In the present work, the impacts of As(V) and low phosphate on intracellular metabolite and lipid profiles of GW4 were quantified using liquid chromatography-mass spectroscopy (LC-MS) in combination with transcriptional assays and the analysis of intracellular ATP and NADH levels. Metabolite profiling revealed that oxidative stress response pathways were altered and suggested an increase in DNA repair. Changes in metabolite levels in the tricarboxylic acid (TCA) cycle along with increased ATP are consistent with As(V)-enhanced growth of A. tumefaciens GW4. Lipidomics analysis revealed that most glycerophospholipids decreased in abundance when As(V) was available. However, several glycerolipid classes increased, an outcome that is consistent with maximizing growth via a phosphate-sparing phenotype. Differentially regulated lipids included phosphotidylcholine and lysophospholipids, which have not been previously reported in A. tumefaciens The metabolites and lipids identified in this study deepen our understanding of the interplay between phosphate and arsenate on chemical and metabolic levels.IMPORTANCE Arsenic is widespread in the environment and is one of the most ubiquitous environmental pollutants. Parodoxically, the growth of certain bacteria is enhanced by arsenic when phosphate is limited. Arsenate and phosphate are chemically similar, and this behavior is believed to represent a phosphate-sparing phenotype in which arsenate is used in place of phosphate in certain biomolecules. The research presented here uses a global approach to track metabolic changes in an environmentally relevant bacterium during exposure to arsenate when phosphate is low. Our findings are relevant for understanding the environmental fate of arsenic as well as how human-associated microbiomes respond to this common toxin.
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Luo Z, Wang Z, Liu A, Yan Y, Wu Y, Zhang X. New insights into toxic effects of arsenate on four Microcystis species under different phosphorus regimes. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:44460-44469. [PMID: 32770468 DOI: 10.1007/s11356-020-10396-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 08/03/2020] [Indexed: 06/11/2023]
Abstract
Very little information is available on the stressed growth of Microcystis imposed by arsenate (As(V)) under different phosphorus (P) regimes. In this study, we examined the growth characteristics and arsenic transformation of four Microcystis species exposed under As(V) with two P sources involving dissolved inorganic phosphorus (IP) and organophosphate (D-glucose-6-phosphate disodium salt, GP). Results showed that all the four chosen Microcystis species could grow and reproduce with GP as the only P source, and the difference was insignificant when compared with IP. From optical density (OD), chlorophyll a (Chla), and actual quantum yield (Yield), the tolerance to As(V) of the chosen species was following as FACHB 905 > FACHB 1028 > FACHB 1334 > FACHB 912. Specifically, the 96 h EC50 of As(V) for FACHB 905 in IP was approx. 4 orders of magnitude higher than that in GP, but for other three algal species, the 96 h EC50 values were similar under the two given different P conditions. Furthermore, all antioxidant enzyme activities of superoxide dismutase (SOD), peroxide dismutase (POD), glutathione S-transferases (GSTs), and metalloproteinase (MTs) in algal cells were significantly increased in GP conditions. Moreover, the enzyme activities of AKP, GSTs, and MTs were inhibited with increasing As(V) levels under both IP and GP conditions. In addition, arsenite (As(III)) and methylated As of monomethylarsonic acid (MMA) and dimethylthioarsinic acid (DMA) were found in FACHB 912 and FACHB 1334 media, indicating that these Microcystis could detoxify As(V) by As biotransformation under IP and GP conditions. Specifically, As(V) reduction was elevated in media of FACHB 1334 and FACHB 905, but was decreased in media of FACHB 912 under GP conditions. Our results highlight the different P sources that impact the toxic effects of arsenate exposure on Microcystis and subsequent As biotransformation.
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Affiliation(s)
- Zhuanxi Luo
- College of Chemical Engineering and Fujian Provincial Key Laboratory of Biochemical Technology, Huaqiao University, Xiamen, 361021, China.
- Key Laboratory of Karst Dynamics, MNR & Guangxi, Institute of Karst Geology, CAGS, Guilin, 541004, China.
| | - Zhenhong Wang
- College of Chemistry and Environment and Fujian Province Key Laboratory of Modern Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou, 363000, China
| | - Aifen Liu
- College of Chemistry and Environment and Fujian Province Key Laboratory of Modern Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou, 363000, China
| | - Yu Yan
- College of Chemical Engineering and Fujian Provincial Key Laboratory of Biochemical Technology, Huaqiao University, Xiamen, 361021, China
| | - Yaqing Wu
- Instrumental Analysis Center of Huaqiao University, Xiamen, 361021, China
| | - Xiaoyong Zhang
- Center of Environmental Emergency Response and Accident Investigation of Jiangsu Province, Nanjing, 210036, China
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11
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Zhao R, Xie CT, Xu Y, Ji DH, Chen CS, Ye J, Xue XM, Wang WL. The response of Pyropia haitanensis to inorganic arsenic under laboratory culture. CHEMOSPHERE 2020; 261:128160. [PMID: 33113648 DOI: 10.1016/j.chemosphere.2020.128160] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/15/2020] [Accepted: 08/25/2020] [Indexed: 06/11/2023]
Abstract
Up to now, complicated organoarsenicals were mainly identified in marine organisms, suggesting that these organisms play a critical role in arsenic biogeochemical cycling because of low phosphate and relatively high arsenic concentration in the marine environment. However, the response of marine macroalgae to inorganic arsenic remains unknown. In this study, Pyropia haitanensis were exposed to arsenate [As(V)] (0.1, 1, 10, 100 μM) or arsenite [As(III)] (0.1, 1, 10 μM) under laboratory conditions for 3 d. The species of water-soluble arsenic, the total concentration of lipid-soluble and cell residue arsenic of the algae cells was analyzed. As(V) was mainly transformed into oxo-arsenosugar-phosphate, with other arsenic compounds such as monomethylated, As(III), demethylated arsenic and oxo-arsenosugar-glycerol being likely the intermediates of arsenosugar synthesis. When high concentration of As(III) was toxic to P. haitanensis, As(III) entered into the cells and was transformed into less toxic organoarsenicals and As(V). Transcriptome results showed genes involved in DNA replication, mismatch repair, base excision repair, and nucleotide excision repair were up-regulated in the algae cells exposed to 10 μM As(V), and multiple genes involved in glutathione metabolism and photosynthetic were up-regulated by 1 μM As(III). A large number of ABC transporters were down-regulated by As(V) while ten genes related to ABC transporters were up-regulated by As(III), indicating that ABC transporters were involved in transporting As(III) to vacuoles in algae cells. These results indicated that P. haitanensis detoxifies inorganic arsenic via transforming them into organoarsenicals and enhancing the isolation of highly toxic As(III) in vacuoles.
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Affiliation(s)
- Rong Zhao
- Fisheries College, Jimei University, Xiamen, 361021, China
| | - Chao-Tian Xie
- Fisheries College, Jimei University, Xiamen, 361021, China
| | - Yan Xu
- Fisheries College, Jimei University, Xiamen, 361021, China
| | - De-Hua Ji
- Fisheries College, Jimei University, Xiamen, 361021, China
| | | | - Jun Ye
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China; College of Life Sciences, Hebei University, Baoding, 071000, China
| | - Xi-Mei Xue
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.
| | - Wen-Lei Wang
- Fisheries College, Jimei University, Xiamen, 361021, China.
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12
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Pileggi M, Pileggi SA, Sadowsky MJ. Herbicide bioremediation: from strains to bacterial communities. Heliyon 2020; 6:e05767. [PMID: 33392402 PMCID: PMC7773584 DOI: 10.1016/j.heliyon.2020.e05767] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 08/23/2020] [Accepted: 12/15/2020] [Indexed: 01/12/2023] Open
Abstract
There is high demand for herbicides based on the necessity to increase crop production to satisfy world-wide demands. Nevertheless, there are negative impacts of herbicide use, manifesting as selection for resistant weeds, production of toxic metabolites from partial degradation of herbicides, changes in soil microbial communities and biogeochemical cycles, alterations in plant nutrition and soil fertility, and persistent environmental contamination. Some herbicides damage non-target microorganisms via directed interference with host metabolism and via oxidative stress mechanisms. For these reasons, it is necessary to identify sustainable, efficient methods to mitigate these environmental liabilities. Before the degradation process can be initiated by microbial enzymes and metabolic pathways, microorganisms need to tolerate the oxidative stresses caused by the herbicides themselves. This can be achieved via a complex system of enzymatic and non-enzymatic antioxidative stress systems. Many of these response systems are not herbicide specific, but rather triggered by a variety of substances. Collectively, these nonspecific response systems enhance the survival and fitness potential of microorganisms. Biodegradation studies and remediation approaches have relied on individually selected strains to effectively remediate herbicides in the environment. Nevertheless, it has been shown that microbial communication systems that modulate social relationships and metabolic pathways inside biofilm structures among microorganisms are complex; therefore, use of isolated strains for xenobiotic degradation needs to be enhanced using a community-based approach with biodegradation pathway integration. Bioremediation efforts can use omics-based technologies to gain a deeper understanding of the molecular complexes of bacterial communities to achieve to more efficient elimination of xenobiotics. With this knowledge, the possibility of altering microbial communities is increased to improve the potential for bioremediation without causing other environmental impacts not anticipated by simpler approaches. The understanding of microbial community dynamics in free-living microbiota and those present in complex communities and in biofilms is paramount to achieving these objectives. It is also essential that non-developed countries, which are major food producers and consumers of pesticides, have access to these techniques to achieve sustainable production, without causing impacts through unknown side effects.
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Affiliation(s)
- Marcos Pileggi
- Laboratory of Environmental Microbiology, Biological Science and Health Institute, Department of Structural and Molecular Biology, and Genetics, State University of Ponta Grossa, Ponta Grossa, Paraná, Brazil
| | - Sônia A.V. Pileggi
- Laboratory of Environmental Microbiology, Biological Science and Health Institute, Department of Structural and Molecular Biology, and Genetics, State University of Ponta Grossa, Ponta Grossa, Paraná, Brazil
| | - Michael J. Sadowsky
- The Biotechnology Institute, Department of Soil, Water, and Climate, Department of Plant and Microbial Biology, University of Minnesota, Saint Paul, MN, USA
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13
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Arsenic-contaminated sediment from mining areas as source of morphological and phylogenetic distinct cyanobacterial lineages. ALGAL RES 2019. [DOI: 10.1016/j.algal.2019.101589] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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14
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Firrincieli A, Presentato A, Favoino G, Marabottini R, Allevato E, Stazi SR, Scarascia Mugnozza G, Harfouche A, Petruccioli M, Turner RJ, Zannoni D, Cappelletti M. Identification of Resistance Genes and Response to Arsenic in Rhodococcus aetherivorans BCP1. Front Microbiol 2019; 10:888. [PMID: 31133997 PMCID: PMC6514093 DOI: 10.3389/fmicb.2019.00888] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 04/08/2019] [Indexed: 11/28/2022] Open
Abstract
Arsenic (As) ranks among the priority metal(loid)s that are of public health concern. In the environment, arsenic is present in different forms, organic or inorganic, featured by various toxicity levels. Bacteria have developed different strategies to deal with this toxicity involving different resistance genetic determinants. Bacterial strains of Rhodococcus genus, and more in general Actinobacteria phylum, have the ability to cope with high concentrations of toxic metalloids, although little is known on the molecular and genetic bases of these metabolic features. Here we show that Rhodococcus aetherivorans BCP1, an extremophilic actinobacterial strain able to tolerate high concentrations of organic solvents and toxic metalloids, can grow in the presence of high concentrations of As(V) (up to 240 mM) under aerobic growth conditions using glucose as sole carbon and energy source. Notably, BCP1 cells improved their growth performance as well as their capacity of reducing As(V) into As(III) when the concentration of As(V) is within 30–100 mM As(V). Genomic analysis of BCP1 compared to other actinobacterial strains revealed the presence of three gene clusters responsible for organic and inorganic arsenic resistance. In particular, two adjacent and divergently oriented ars gene clusters include three arsenate reductase genes (arsC1/2/3) involved in resistance mechanisms against As(V). A sequence similarity network (SSN) and phylogenetic analysis of these arsenate reductase genes indicated that two of them (ArsC2/3) are functionally related to thioredoxin (Trx)/thioredoxin reductase (TrxR)-dependent class and one of them (ArsC1) to the mycothiol (MSH)/mycoredoxin (Mrx)-dependent class. A targeted transcriptomic analysis performed by RT-qPCR indicated that the arsenate reductase genes as well as other genes included in the ars gene cluster (possible regulator gene, arsR, and arsenite extrusion genes, arsA, acr3, and arsD) are transcriptionally induced when BCP1 cells were exposed to As(V) supplied at two different sub-lethal concentrations. This work provides for the first time insights into the arsenic resistance mechanisms of a Rhodococcus strain, revealing some of the unique metabolic requirements for the environmental persistence of this bacterial genus and its possible use in bioremediation procedures of toxic metal contaminated sites.
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Affiliation(s)
- Andrea Firrincieli
- Department for the Innovation in Biological Systems, Agro-Food and Forestry, University of Tuscia, Viterbo, Italy
| | - Alessandro Presentato
- Department of Biotechnology, University of Verona, Verona, Italy.,Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Giusi Favoino
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Rosita Marabottini
- Department for the Innovation in Biological Systems, Agro-Food and Forestry, University of Tuscia, Viterbo, Italy
| | - Enrica Allevato
- Department for the Innovation in Biological Systems, Agro-Food and Forestry, University of Tuscia, Viterbo, Italy
| | - Silvia Rita Stazi
- Department for the Innovation in Biological Systems, Agro-Food and Forestry, University of Tuscia, Viterbo, Italy
| | - Giuseppe Scarascia Mugnozza
- Department for the Innovation in Biological Systems, Agro-Food and Forestry, University of Tuscia, Viterbo, Italy
| | - Antoine Harfouche
- Department for the Innovation in Biological Systems, Agro-Food and Forestry, University of Tuscia, Viterbo, Italy
| | - Maurizio Petruccioli
- Department for the Innovation in Biological Systems, Agro-Food and Forestry, University of Tuscia, Viterbo, Italy
| | - Raymond J Turner
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Davide Zannoni
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Martina Cappelletti
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
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15
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Xue XM, Ye J, Raber G, Rosen BP, Francesconi K, Xiong C, Zhu Z, Rensing C, Zhu YG. Identification of Steps in the Pathway of Arsenosugar Biosynthesis. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:634-641. [PMID: 30525501 PMCID: PMC6467767 DOI: 10.1021/acs.est.8b04389] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Arsenosugars are arsenic-containing ribosides that play a substantial role in arsenic biogeochemical cycles. Arsenosugars were identified more than 30 years ago, and yet their mechanism of biosynthesis remains unknown. In this study we report identification of the arsS gene from the cyanobacterium Synechocystis sp. PCC 6803 and show that it is involved in arsenosugar biosynthesis. In the Synechocystis sp. PCC 6803 ars operon, arsS is adjacent to the arsM gene that encodes an As(III) S-adenosylmethionine (SAM) methyltransferase. The gene product, ArsS, contains a characteristic CX3CX2C motif which is typical for the radical SAM superfamily. The function of ArsS was identified from a combination of arsS disruption in Synechocystis sp. PCC 6803 and heterologous expression of arsM and arsS in Escherichia coli. Both genes are necessary, indicating a multistep pathway of arsenosugar biosynthesis. In addition, we demonstrate that ArsS orthologs from three other freshwater cyanobacteria and one picocyanobacterium are involved in arsenosugar biosynthesis in those microbes. This study represents the identification of the first two steps in the pathway of arsenosugar biosynthesis. Our discovery expands the catalytic repertoire of the diverse radical SAM enzyme superfamily and provides a basis for studying the biogeochemistry of complex organoarsenicals.
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Affiliation(s)
- Xi-Mei Xue
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Jun Ye
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Georg Raber
- Institute of Chemistry, NAWI Graz, University of Graz, Graz 8010, Austria
| | - Barry P. Rosen
- Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, Florida 33199, United States
| | - Kevin Francesconi
- Institute of Chemistry, NAWI Graz, University of Graz, Graz 8010, Austria
| | - Chan Xiong
- Institute of Chemistry, NAWI Graz, University of Graz, Graz 8010, Austria
| | - Zhe Zhu
- Department of Chemical and Environmental Engineering, Faculty of Science and Engineering, University of Nottingham, Ningbo 315100, China
| | - Christopher Rensing
- College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yong-Guan Zhu
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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16
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Fru EC, Callac N, Posth NR, Argyraki A, Ling YC, Ivarsson M, Broman C, Kilias SP. Arsenic and high affinity phosphate uptake gene distribution in shallow submarine hydrothermal sediments. BIOGEOCHEMISTRY 2018; 141:41-62. [PMID: 30956374 PMCID: PMC6413627 DOI: 10.1007/s10533-018-0500-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 09/14/2018] [Indexed: 05/27/2023]
Abstract
The toxicity of arsenic (As) towards life on Earth is apparent in the dense distribution of genes associated with As detoxification across the tree of life. The ability to defend against As is particularly vital for survival in As-rich shallow submarine hydrothermal ecosystems along the Hellenic Volcanic Arc (HVA), where life is exposed to hydrothermal fluids containing up to 3000 times more As than present in seawater. We propose that the removal of dissolved As and phosphorus (P) by sulfide and Fe(III)(oxyhydr)oxide minerals during sediment-seawater interaction, produces nutrient-deficient porewaters containing < 2.0 ppb P. The porewater arsenite-As(III) to arsenate-As(V) ratios, combined with sulfide concentration in the sediment and/or porewater, suggest a hydrothermally-induced seafloor redox gradient. This gradient overlaps with changing high affinity phosphate uptake gene abundance. High affinity phosphate uptake and As cycling genes are depleted in the sulfide-rich settings, relative to the more oxidizing habitats where mainly Fe(III)(oxyhydr)oxides are precipitated. In addition, a habitat-wide low As-respiring and As-oxidizing gene content relative to As resistance gene richness, suggests that As detoxification is prioritized over metabolic As cycling in the sediments. Collectively, the data point to redox control on Fe and S mineralization as a decisive factor in the regulation of high affinity phosphate uptake and As cycling gene content in shallow submarine hydrothermal ecosystems along the HVA.
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Affiliation(s)
- Ernest Chi Fru
- Department of Geological Sciences and Bolin Center for Climate Research, Stockholm University, 106 91 Stockholm, Sweden
- College of Physical Sciences and Engineering, School of Earth and Ocean Sciences, Geobiology Center, Cardiff University, Park Place, Cardiff, Wales CF10 3AT UK
| | - Nolwenn Callac
- Department of Geological Sciences and Bolin Center for Climate Research, Stockholm University, 106 91 Stockholm, Sweden
| | - Nicole R. Posth
- Department of Biology, Nordic Center for Earth Evolution (NordCEE), Campusvej 55, 5230 Odense M, Denmark
- Department of Geosciences & Natural Resource Management, Geology Section, University of Copenhagen, Øster Voldgade 10, 1350 Copenhagen K, Denmark
| | - Ariadne Argyraki
- Department of Geology and Geoenvironment, National and Kapodistrian University of Athens, Panepistimiopolis Zographou, 157 84 Athens, Greece
| | - Yu-Chen Ling
- College of Physical Sciences and Engineering, School of Earth and Ocean Sciences, Geobiology Center, Cardiff University, Park Place, Cardiff, Wales CF10 3AT UK
| | - Magnus Ivarsson
- Department of Biology, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| | - Curt Broman
- Department of Geological Sciences and Bolin Center for Climate Research, Stockholm University, 106 91 Stockholm, Sweden
| | - Stephanos P. Kilias
- Department of Geology and Geoenvironment, National and Kapodistrian University of Athens, Panepistimiopolis Zographou, 157 84 Athens, Greece
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17
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Patel A, Tiwari S, Prasad SM. Toxicity assessment of arsenate and arsenite on growth, chlorophyll a fluorescence and antioxidant machinery in Nostoc muscorum. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2018; 157:369-379. [PMID: 29631092 DOI: 10.1016/j.ecoenv.2018.03.056] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 03/20/2018] [Accepted: 03/23/2018] [Indexed: 05/13/2023]
Abstract
The present study deals with impact of varied doses of arsenite (AsIII; 50, 100 and 150 µM) and arsenate (AsV; 50, 100 and 150 mM) on growth, photosynthetic pigments, photochemistry of photosystem II, oxidative biomarkers, (O2•¯, H2O2 and MDA equivalents contents) and activity of antioxidant enzymes in diazotrophic cyanobacterium Nostoc muscorum after 48 and 96 h of the treatments. The reduction in growth, pigment contents (Chl a, Phy and Car) and PS II photochemistry was found to increase with enhanced accumulation of test metal in cells, and the damaging effect on photosynthetic pigments showed the order (Phy > chl a> Car). The negative effect on PS II photochemistry was due to significant decrease in the value of JIP kinetics ϕP0, FV/F0, ϕE0,Ψ0 and PIABS except F0/FV and significant rise in values of energy flux parameters such as ABS/RC, TR0/RC, ET0/RC and DI0/RC. Both the species of arsenic caused significant rise in oxidative biomarkers as evident by in vitro and in vivo analysis of (O2•¯, H2O2 and MDA equivalents contents) despite of appreciable rise in the activity antioxidative enzymes such as SOD, POD, CAT and GST. The study concludes that in among both forms of arsenic, arsenite effect was more dominant on growth, photosynthetic pigments; oxidative stress biomarkers as evident by weak induction of anti-oxidative defense system to overcome the stress as compared to arsenate.
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Affiliation(s)
- Anuradha Patel
- Ranjan Plant physiology and Biochemistry Laboratory, Department of Botany, University of Allahabad, Allahabad 211002, India
| | - Sanjesh Tiwari
- Ranjan Plant physiology and Biochemistry Laboratory, Department of Botany, University of Allahabad, Allahabad 211002, India
| | - Sheo Mohan Prasad
- Ranjan Plant physiology and Biochemistry Laboratory, Department of Botany, University of Allahabad, Allahabad 211002, India.
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18
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Campoy-Diaz AD, Arribére MA, Guevara SR, Vega IA. Bioindication of mercury, arsenic and uranium in the apple snail Pomacea canaliculata (Caenogastropoda, Ampullariidae): Bioconcentration and depuration in tissues and symbiotic corpuscles. CHEMOSPHERE 2018; 196:196-205. [PMID: 29304457 DOI: 10.1016/j.chemosphere.2017.12.145] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2017] [Revised: 12/19/2017] [Accepted: 12/22/2017] [Indexed: 06/07/2023]
Abstract
Pomacea canaliculata is a mollusk potentially useful as a biomonitor species of freshwater quality. This work explores the ability of snail tissues and symbiotic corpuscles to bioconcentrate and depurate mercury, arsenic, and uranium. Adult snails cultured in metal-free reconstituted water were exposed for eight weeks (bioaccumulation phase) to water with Hg (2 μgL-1), As (10 μgL-1), and U (30 μgL-1) and then returned to the reconstituted water for other additional eight weeks (depuration phase). Elemental concentrations in digestive gland, kidney, symbiotic corpuscles and particulate excreta were determined by neutron activation analysis. The glandular symbiotic occupancy was measured by morphometric analysis. After exposure, the kidney showed the highest concentration of Hg, while the digestive gland accumulated mainly As and U. The subcellular distribution in symbiotic corpuscles was ∼71%, ∼48%, and ∼11% for U, Hg, and As, respectively. Tissue depuration between weeks 8 and 16 was variable amongst elements. At week 16, the tissue depuration of U was the highest (digestive gland = 92%; kidney = 80%), while it was lower for Hg (digestive gland = 51%; kidney = 53%). At week 16, arsenic showed a differential pattern of tissue depuration (digestive gland = 23%; kidney = 88%). The symbiotic detoxification of the three elements in excreta was fast between weeks 8 and 10 and it was slower after on. At the end of the depuration, each element distributed differentially in digestive gland and symbiotic corpuscles. Our findings show that symbiotic corpuscles, digestive gland and kidney P. canaliculata are sensitive places for biomonitoring of Hg, As and U.
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Affiliation(s)
- Alejandra D Campoy-Diaz
- IHEM, CONICET, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina; Universidad Nacional de Cuyo, Facultad de Ciencias Médicas, Instituto de Fisiología, 5500 Mendoza, Argentina
| | - María A Arribére
- Instituto Balseiro, Universidad Nacional de Cuyo, Comisión Nacional de Energía Atómica, 8400 Bariloche, Argentina
| | - Sergio Ribeiro Guevara
- Instituto Balseiro, Universidad Nacional de Cuyo, Comisión Nacional de Energía Atómica, 8400 Bariloche, Argentina
| | - Israel A Vega
- IHEM, CONICET, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina; Universidad Nacional de Cuyo, Facultad de Ciencias Médicas, Instituto de Fisiología, 5500 Mendoza, Argentina; Universidad Nacional de Cuyo, Facultad de Ciencias Exactas y Naturales, Departamento de Biología, 5500 Mendoza, Argentina.
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19
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Andreote APD, Dini-Andreote F, Rigonato J, Machineski GS, Souza BCE, Barbiero L, Rezende-Filho AT, Fiore MF. Contrasting the Genetic Patterns of Microbial Communities in Soda Lakes with and without Cyanobacterial Bloom. Front Microbiol 2018; 9:244. [PMID: 29520256 PMCID: PMC5827094 DOI: 10.3389/fmicb.2018.00244] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 01/31/2018] [Indexed: 11/29/2022] Open
Abstract
Soda lakes have high levels of sodium carbonates and are characterized by salinity and elevated pH. These ecosystems are found across Africa, Europe, Asia, Australia, North, Central, and South America. Particularly in Brazil, the Pantanal region has a series of hundreds of shallow soda lakes (ca. 600) potentially colonized by a diverse haloalkaliphilic microbial community. Biological information of these systems is still elusive, in particular data on the description of the main taxa involved in the biogeochemical cycling of life-important elements. Here, we used metagenomic sequencing to contrast the composition and functional patterns of the microbial communities of two distinct soda lakes from the sub-region Nhecolândia, state of Mato Grosso do Sul, Brazil. These two lakes differ by permanent cyanobacterial blooms (Salina Verde, green-water lake) and by no record of cyanobacterial blooms (Salina Preta, black-water lake). The dominant bacterial species in the Salina Verde bloom was Anabaenopsis elenkinii. This cyanobacterium altered local abiotic parameters such as pH, turbidity, and dissolved oxygen and consequently the overall structure of the microbial community. In Salina Preta, the microbial community had a more structured taxonomic profile. Therefore, the distribution of metabolic functions in Salina Preta community encompassed a large number of taxa, whereas, in Salina Verde, the functional potential was restrained across a specific set of taxa. Distinct signatures in the abundance of genes associated with the cycling of carbon, nitrogen, and sulfur were found. Interestingly, genes linked to arsenic resistance metabolism were present at higher abundance in Salina Verde and they were associated with the cyanobacterial bloom. Collectively, this study advances fundamental knowledge on the composition and genetic potential of microbial communities inhabiting tropical soda lakes.
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Affiliation(s)
- Ana P. D. Andreote
- Center for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, Brazil
| | - Francisco Dini-Andreote
- Microbial Ecology Cluster, Genomics Research in Ecology and Evolution in Nature, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, Netherlands
| | - Janaina Rigonato
- Center for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, Brazil
| | | | - Bruno C. E. Souza
- Center for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, Brazil
| | - Laurent Barbiero
- Observatoire Midi-Pyrénées, Géosciences Environnement Toulouse, Institut de Recherche pour le Développement, Centre National de la Recherche Scientifique, Université Paul Sabatier, Toulouse, France
| | - Ary T. Rezende-Filho
- Faculty of Engineering, Architecture and Urbanism and Geography, Federal University of Mato Grosso do Sul, Campo Grande, Brazil
| | - Marli F. Fiore
- Center for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, Brazil
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20
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Yan Y, Xue XM, Guo YQ, Zhu YG, Ye J. Co-expression of Cyanobacterial Genes for Arsenic Methylation and Demethylation in Escherichia coli Offers Insights into Arsenic Resistance. Front Microbiol 2017; 8:60. [PMID: 28174568 PMCID: PMC5258700 DOI: 10.3389/fmicb.2017.00060] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2016] [Accepted: 01/10/2017] [Indexed: 11/15/2022] Open
Abstract
Arsenite [As(III)] and methylarsenite [MAs(III)] are the most toxic inorganic and methylated arsenicals, respectively. As(III) and MAs(III) can be interconverted in the unicellular cyanobacterium Nostoc sp. PCC 7120 (Nostoc), which has both the arsM gene (NsarsM), which is responsible for arsenic methylation, and the arsI gene (NsarsI), which is responsible for MAs(III) demethylation. It is not clear how the cells prevent a futile cycle of methylation and demethylation. To investigate the relationship between arsenic methylation and demethylation, we constructed strains of Escherichia coli AW3110 (ΔarsRBC) expressing NsarsM or/and NsarsI. Expression of NsarsI conferred MAs(III) resistance through MAs(III) demethylation. Compared to NsArsI, NsArsM conferred higher resistance to As(III) and lower resistance to MAs(III) by methylating both As(III) and MAs(III). The major species found in solution was dimethylarsenate [DMAs(V)]. Co-expression of NsarsM and NsarsI conferred As(III) resistance at levels similar to that with NsarsM alone, although the main species found in solution after As(III) biotransformation was methylarsenate [MAs(V)] rather than DMAs(V). Co-expression of NsarsM and NsarsI conferred a higher level of resistance to MAs(III) than found with expression of NsarsM alone but lower than expression of only NsarsI. Cells co-expressing both genes converted MAs(III) to a mixture of As(III) and DMAs(V). In Nostoc NsarsM is constitutively expressed, while NsarsI is inducible by either As(III) or MAs(III). Thus, our results suggest that at low concentrations of arsenic, NsArsM activity predominates, while NsArsI activity predominates at high concentrations. We propose that coexistence of arsM and arsI genes in Nostoc could be advantageous for several reasons. First, it confers a broader spectrum of resistance to both As(III) and MAs(III). Second, at low concentrations of arsenic, the MAs(III) produced by NsArsM will possibly have antibiotic-like properties and give the organism a competitive advantage. Finally, these results shed light on the role of cyanobacteria in the arsenic biogeochemical cycle.
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Affiliation(s)
- Yu Yan
- Key Lab of Urban Environment and Health, Institute of Urban Environment – Chinese Academy of SciencesXiamen, China
- University of Chinese Academy of SciencesBeijing, China
| | - Xi-Mei Xue
- Key Lab of Urban Environment and Health, Institute of Urban Environment – Chinese Academy of SciencesXiamen, China
| | - Yu-Qing Guo
- Key Lab of Urban Environment and Health, Institute of Urban Environment – Chinese Academy of SciencesXiamen, China
- Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, College of Life Sciences, Fujian Agriculture and Forestry UniversityFuzhou, China
| | - Yong-Guan Zhu
- Key Lab of Urban Environment and Health, Institute of Urban Environment – Chinese Academy of SciencesXiamen, China
- State Key Lab of Urban and Regional Ecology, Research Center for Eco-environmental Sciences – Chinese Academy of SciencesBeijing, China
| | - Jun Ye
- Key Lab of Urban Environment and Health, Institute of Urban Environment – Chinese Academy of SciencesXiamen, China
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21
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Tokmina-Lukaszewska M, Shi Z, Tripet B, McDermott TR, Copié V, Bothner B, Wang G. Metabolic response of Agrobacterium tumefaciens 5A to arsenite. Environ Microbiol 2017; 19:710-721. [PMID: 27871140 DOI: 10.1111/1462-2920.13615] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 10/24/2016] [Accepted: 11/16/2016] [Indexed: 11/26/2022]
Abstract
Wide-spread abundance in soil and water, coupled with high toxicity have put arsenic at the top of the list of environmental contaminants. Early studies demonstrated that both concentration and the valence state of inorganic arsenic (arsenite, As(III) vs. arsenate As(V)) can be modulated by microbes. Using genetics, transcriptomic and proteomic techniques, microbe-arsenic detoxification, respiratory As(V) reduction and As(III) oxidation have since been examined. The effect of arsenic exposure on whole-cell intracellular microbial metabolism, however, has not been extensively studied. We combined LC-MS and 1 H NMR to quantify metabolic changes in Agrobacterium tumefaciens (strain 5A) upon exposure to sub-lethal concentrations of As(III). Metabolomics analysis reveals global differences in metabolite concentrations between control and As(III) exposure groups, with significant perturbations to intermediates shuttling into and cycling within the TCA cycle. These data are most consistent with the disruption of two key TCA cycle enzymes, pyruvate dehydrogenase and α-ketoglutarate dehydrogenase. Glycolysis also appeared altered following As(III) stress, with carbon accumulating as complex saccharides. These observations suggest that an important consequence of As(III) contamination in nature will be to alter microbial carbon metabolism at the microbial community level and thus has the potential to foundationally impact all biogeochemical cycles in the environment.
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Affiliation(s)
| | - Zunji Shi
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59717, USA.,State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, P. R. China
| | - Brian Tripet
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59717, USA
| | - Timothy R McDermott
- Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT, 59717, USA
| | - Valérie Copié
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59717, USA
| | - Brian Bothner
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59717, USA
| | - Gejiao Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, P. R. China
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Grim SL, Dick GJ. Photosynthetic Versatility in the Genome of Geitlerinema sp. PCC 9228 (Formerly Oscillatoria limnetica 'Solar Lake'), a Model Anoxygenic Photosynthetic Cyanobacterium. Front Microbiol 2016; 7:1546. [PMID: 27790189 PMCID: PMC5061849 DOI: 10.3389/fmicb.2016.01546] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 09/15/2016] [Indexed: 12/27/2022] Open
Abstract
Anoxygenic cyanobacteria that use sulfide as the electron donor for photosynthesis are a potentially influential but poorly constrained force on Earth's biogeochemistry. Their versatile metabolism may have boosted primary production and nitrogen cycling in euxinic coastal margins in the Proterozoic. In addition, they represent a biological mechanism for limiting the accumulation of atmospheric oxygen, especially before the Great Oxidation Event and in the low-oxygen conditions of the Proterozoic. In this study, we describe the draft genome sequence of Geitlerinema sp. PCC 9228, formerly Oscillatoria limnetica 'Solar Lake', a mat-forming diazotrophic cyanobacterium that can switch between oxygenic photosynthesis and sulfide-based anoxygenic photosynthesis (AP). Geitlerinema possesses three variants of psbA, which encodes protein D1, a core component of the photosystem II reaction center. Phylogenetic analyses indicate that one variant is closely affiliated with cyanobacterial psbA genes that code for a D1 protein used for oxygen-sensitive processes. Another version is phylogenetically similar to cyanobacterial psbA genes that encode D1 proteins used under microaerobic conditions, and the third variant may be cued to high light and/or elevated oxygen concentrations. Geitlerinema has the canonical gene for sulfide quinone reductase (SQR) used in cyanobacterial AP and a putative transcriptional regulatory gene in the same operon. Another operon with a second, distinct sqr and regulatory gene is present, and is phylogenetically related to sqr genes used for high sulfide concentrations. The genome has a comprehensive nif gene suite for nitrogen fixation, supporting previous observations of nitrogenase activity. Geitlerinema possesses a bidirectional hydrogenase rather than the uptake hydrogenase typically used by cyanobacteria in diazotrophy. Overall, the genome sequence of Geitlerinema sp. PCC 9228 highlights potential cyanobacterial strategies to cope with fluctuating redox gradients and nitrogen availability that occur in benthic mats over a diel cycle. Such dynamic geochemical conditions likely also challenged Proterozoic cyanobacteria, modulating oxygen production. The genetic repertoire that underpins flexible oxygenic/anoxygenic photosynthesis in cyanobacteria provides a foundation to explore the regulation, evolutionary context, and biogeochemical implications of these co-occurring metabolisms in Earth history.
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Affiliation(s)
- Sharon L. Grim
- Department of Earth and Environmental Sciences, University of Michigan, Ann ArborMI, USA
| | - Gregory J. Dick
- Department of Earth and Environmental Sciences, University of Michigan, Ann ArborMI, USA
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Sure S, Ackland ML, Gaur A, Gupta P, Adholeya A, Kochar M. Probing Synechocystis-Arsenic Interactions through Extracellular Nanowires. Front Microbiol 2016; 7:1134. [PMID: 27486454 PMCID: PMC4949250 DOI: 10.3389/fmicb.2016.01134] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 07/07/2016] [Indexed: 11/13/2022] Open
Abstract
Microbial nanowires (MNWs) can play an important role in the transformation and mobility of toxic metals/metalloids in environment. The potential role of MNWs in cell-arsenic (As) interactions has not been reported in microorganisms and thus we explored this interaction using Synechocystis PCC 6803 as a model system. The effect of half maximal inhibitory concentration (IC50) [~300 mM As (V) and ~4 mM As (III)] and non-inhibitory [4X lower than IC50, i.e., 75 mM As (V) and 1 mM As (III)] of As was studied on Synechocystis cells in relation to its effect on Chlorophyll (Chl) a, type IV pili (TFP)-As interaction and intracellular/extracellular presence of As. In silico analysis showed that subunit PilA1 of electrically conductive TFP, i.e., microbial nanowires of Synechocystis have putative binding sites for As. In agreement with in silico analysis, transmission electron microscopy analysis showed that As was deposited on Synechocystis nanowires at all tested concentrations. The potential of Synechocystis nanowires to immobilize As can be further enhanced and evaluated on a large scale and thus can be applied for bioremediation studies.
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Affiliation(s)
- Sandeep Sure
- TERI-Deakin Nano biotechnology Centre, The Energy and Resources Institute Gurgaon, India
| | - M L Ackland
- Centre for Cellular & Molecular Biology, Deakin University, Melbourne VIC, Australia
| | - Aditya Gaur
- TERI-Deakin Nano biotechnology Centre, The Energy and Resources Institute Gurgaon, India
| | - Priyanka Gupta
- TERI-Deakin Nano biotechnology Centre, The Energy and Resources Institute Gurgaon, India
| | - Alok Adholeya
- TERI-Deakin Nano biotechnology Centre, The Energy and Resources Institute Gurgaon, India
| | - Mandira Kochar
- TERI-Deakin Nano biotechnology Centre, The Energy and Resources Institute Gurgaon, India
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Uchiyama J, Kanesaki Y, Iwata N, Asakura R, Funamizu K, Tasaki R, Agatsuma M, Tahara H, Matsuhashi A, Yoshikawa H, Ogawa S, Ohta H. Genomic analysis of parallel-evolved cyanobacterium Synechocystis sp. PCC 6803 under acid stress. PHOTOSYNTHESIS RESEARCH 2015; 125:243-54. [PMID: 25736465 DOI: 10.1007/s11120-015-0111-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 02/25/2015] [Indexed: 05/06/2023]
Abstract
Experimental evolution is a powerful tool for clarifying phenotypic and genotypic changes responsible for adaptive evolution. In this study, we isolated acid-adapted Synechocystis sp. PCC 6803 (Synechocystis 6803) strains to identify genes involved in acid tolerance. Synechocystis 6803 is rarely found in habitants with pH < 5.75. The parent (P) strain was cultured in BG-11 at pH 6.0. We gradually lowered the pH of the medium from pH 6.0 to pH 5.5 over 3 months. Our adapted cells could grow in acid stress conditions at pH 5.5, whereas the parent cells could not. We performed whole-genome sequencing and compared the acid-adapted and P strains, thereby identifying 11 SNPs in the acid-adapted strains, including in Fo F1-ATPase. To determine whether the SNP genes responded to acid stress, we examined gene expression in the adapted strains using quantitative reverse-transcription polymerase chain reaction. sll0914, sll1496, sll0528, and sll1144 expressions increased under acid stress in the P strain, whereas sll0162, sll0163, slr0623, and slr0529 expressions decreased. There were no differences in the SNP genes expression levels between the P strain and two adapted strains, except for sll0528. These results suggest that SNPs in certain genes are involved in acid stress tolerance in Synechocystis 6803.
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Affiliation(s)
- Junji Uchiyama
- Research Center for RNA Science, Research Institute for Science and Technology, Tokyo University of Science, 2641, Yamasaki, Noda, Chiba, 278-8510, Japan,
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Monsieurs P, Hobman J, Vandenbussche G, Mergeay M, Van Houdt R. Response of Cupriavidus metallidurans CH34 to Metals. ACTA ACUST UNITED AC 2015. [DOI: 10.1007/978-3-319-20594-6_3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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Responses to oxidative and heavy metal stresses in cyanobacteria: recent advances. Int J Mol Sci 2014; 16:871-86. [PMID: 25561236 PMCID: PMC4307280 DOI: 10.3390/ijms16010871] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Accepted: 12/24/2014] [Indexed: 12/24/2022] Open
Abstract
Cyanobacteria, the only known prokaryotes that perform oxygen-evolving photosynthesis, are receiving strong attention in basic and applied research. In using solar energy, water, CO2 and mineral salts to produce a large amount of biomass for the food chain, cyanobacteria constitute the first biological barrier against the entry of toxics into the food chain. In addition, cyanobacteria have the potential for the solar-driven carbon-neutral production of biofuels. However, cyanobacteria are often challenged by toxic reactive oxygen species generated under intense illumination, i.e., when their production of photosynthetic electrons exceeds what they need for the assimilation of inorganic nutrients. Furthermore, in requiring high amounts of various metals for growth, cyanobacteria are also frequently affected by drastic changes in metal availabilities. They are often challenged by heavy metals, which are increasingly spread out in the environment through human activities, and constitute persistent pollutants because they cannot be degraded. Consequently, it is important to analyze the protection against oxidative and metal stresses in cyanobacteria because these ancient organisms have developed most of these processes, a large number of which have been conserved during evolution. This review summarizes what is known regarding these mechanisms, emphasizing on their crosstalk.
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Huertas MJ, López-Maury L, Giner-Lamia J, Sánchez-Riego AM, Florencio FJ. Metals in cyanobacteria: analysis of the copper, nickel, cobalt and arsenic homeostasis mechanisms. Life (Basel) 2014; 4:865-86. [PMID: 25501581 PMCID: PMC4284471 DOI: 10.3390/life4040865] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 11/27/2014] [Accepted: 12/04/2014] [Indexed: 11/16/2022] Open
Abstract
Traces of metal are required for fundamental biochemical processes, such as photosynthesis and respiration. Cyanobacteria metal homeostasis acquires an important role because the photosynthetic machinery imposes a high demand for metals, making them a limiting factor for cyanobacteria, especially in the open oceans. On the other hand, in the last two centuries, the metal concentrations in marine environments and lake sediments have increased as a result of several industrial activities. In all cases, cells have to tightly regulate uptake to maintain their intracellular concentrations below toxic levels. Mechanisms to obtain metal under limiting conditions and to protect cells from an excess of metals are present in cyanobacteria. Understanding metal homeostasis in cyanobacteria and the proteins involved will help to evaluate the use of these microorganisms in metal bioremediation. Furthermore, it will also help to understand how metal availability impacts primary production in the oceans. In this review, we will focus on copper, nickel, cobalt and arsenic (a toxic metalloid) metabolism, which has been mainly analyzed in model cyanobacterium Synechocystis sp. PCC 6803.
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Affiliation(s)
- María José Huertas
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Américo Vespucio 49, E-41092 Sevilla, Spain.
| | - Luis López-Maury
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Américo Vespucio 49, E-41092 Sevilla, Spain.
| | - Joaquín Giner-Lamia
- Systems Biology and Bioinformatics Laboratory, IBB-CBME, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal.
| | - Ana María Sánchez-Riego
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Américo Vespucio 49, E-41092 Sevilla, Spain.
| | - Francisco Javier Florencio
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Américo Vespucio 49, E-41092 Sevilla, Spain.
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