1
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Smythers AL, Crislip JR, Slone DR, Flinn BB, Chaffins JE, Camp KA, McFeeley EW, Kolling DRJ. Excess manganese increases photosynthetic activity via enhanced reducing center and antenna plasticity in Chlorella vulgaris. Sci Rep 2023; 13:11301. [PMID: 37438371 DOI: 10.1038/s41598-023-35895-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Accepted: 05/25/2023] [Indexed: 07/14/2023] Open
Abstract
Photosynthesis relies on many easily oxidizable/reducible transition metals found in the metalloenzymes that make up much of the photosynthetic electron transport chain (ETC). One of these is manganese, an essential cofactor of photosystem II (PSII) and a component of the oxygen-evolving complex, the only biological entity capable of oxidizing water. Additionally, manganese is a cofactor in enzymatic antioxidants, notably the superoxide dismutases-which are localized to the chloroplastic membrane. However, unlike other metals found in the photosynthetic ETC, previous research has shown exposure to excess manganese enhances photosynthetic activity rather than diminishing it. In this study, the impact of PSII heterogeneity on overall performance was investigated using chlorophyll fluorescence, a rapid, non-invasive technique that probed for overall photosynthetic efficiency, reducing site activity, and antenna size and distribution. These measurements unveiled an enhanced plasticity of PSII following excess manganese exposure, in which overall performance and reducing center activity increased while antenna size and proportion of PSIIβ centers decreased. This enhanced activity suggests manganese may hold the key to improving photosynthetic efficiency beyond that which is observed in nature.
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Affiliation(s)
- Amanda L Smythers
- Department of Chemistry, Marshall University, Huntington, WV, USA
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | | | - Danielle R Slone
- Department of Chemistry, Marshall University, Huntington, WV, USA
| | - Brendin B Flinn
- Department of Chemistry, Marshall University, Huntington, WV, USA
| | | | - Kristen A Camp
- Department of Chemistry, Marshall University, Huntington, WV, USA
| | - Eli W McFeeley
- Department of Chemistry, Marshall University, Huntington, WV, USA
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2
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Liu L, Pan Y, Zhi X, Chen L, Zhu H. Bacterial antioxidant mechanism in calcium peroxide aided sludge anaerobic fermentation. BIORESOURCE TECHNOLOGY 2023; 384:129327. [PMID: 37328013 DOI: 10.1016/j.biortech.2023.129327] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 05/13/2023] [Accepted: 06/11/2023] [Indexed: 06/18/2023]
Abstract
Although calcium peroxide (CaO2) can enhance the short-chain fatty acids (SCFAs) production in sludge anaerobic fermentation, the microbiological mechanisms underlying this process remain unclear. In this study, it is aimed to elucidate the bacterial protective mechanisms in response to the oxidative stress induced by CaO2. Results show that extracellular polymeric substance (EPS) and anti-oxidant enzymes play vital roles in protecting bacterial cells from CaO2. The addition of CaO2 resulted in increased relative abundances of genes exoP and SRP54, which are associated with EPS secretion and transportation. Superoxide dismutase (SOD) played a crucial in alleviating oxidative stress. The dosage of CaO2 significantly influences the succession of the bacterial community in the anaerobic fermentation system. With 0.3 g CaO2/g VSS, the net income was approximately 4 USD/ton of sludge treated. The CaO2-assisted anaerobic fermentation process has the potential to recover more resources from sludge and thus, benefit the environment.
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Affiliation(s)
- Li Liu
- Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Yu Pan
- Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Xiaohan Zhi
- Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Long Chen
- Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Hongtao Zhu
- Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China.
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3
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Norton-Baker B, Rocha MA, Granger-Jones J, Fishman DA, Martin RW. Human γS-Crystallin Resists Unfolding Despite Extensive Chemical Modification from Exposure to Ionizing Radiation. J Phys Chem B 2022; 126:679-690. [PMID: 35021623 PMCID: PMC9977691 DOI: 10.1021/acs.jpcb.1c08157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ionizing radiation has dramatic effects on living organisms, causing damage to proteins, DNA, and other cellular components. γ radiation produces reactive oxygen species (ROS) that damage biological macromolecules. Protein modification due to interactions with hydroxyl radical is one of the most common deleterious effects of radiation. The human eye lens is particularly vulnerable to the effects of ionizing radiation, as it is metabolically inactive and its proteins are not recycled after early development. Therefore, radiation damage accumulates and eventually can lead to cataract formation. Here we explore the impact of γ radiation on a long-lived structural protein. We exposed the human eye lens protein γS-crystallin (HγS) to high doses of γ radiation and investigated the chemical and structural effects. HγS accumulated many post-translational modifications (PTMs), appearing to gain significant oxidative damage. Biochemical assays suggested that cysteines were affected, with the concentration of free thiol reduced with increasing γ radiation exposure. SDS-PAGE analysis showed that irradiated samples form protein-protein cross-links, including nondisulfide covalent bonds. Tandem mass spectrometry on proteolytic digests of irradiated samples revealed that lysine, methionine, tryptophan, leucine, and cysteine were oxidized. Despite these chemical modifications, HγS remained folded past 10.8 kGy of γ irradiation as evidenced by circular dichroism and intrinsic tryptophan fluorescence spectroscopy.
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Affiliation(s)
- Brenna Norton-Baker
- These authors contributed equally.,Department of Chemistry, University of California, Irvine, CA 92697-2025, USA
| | - Megan A. Rocha
- These authors contributed equally.,Department of Chemistry, University of California, Irvine, CA 92697-2025, USA
| | | | - Dmitry A. Fishman
- Department of Chemistry, University of California, Irvine, CA 92697-2025, USA
| | - Rachel W. Martin
- Department of Chemistry, University of California, Irvine, CA 92697-2025, USA,Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697-3900, USA
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4
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Gelsinger DR, Reddy R, Whittington K, Debic S, DiRuggiero J. Post-transcriptional regulation of redox homeostasis by the small RNA SHOxi in haloarchaea. RNA Biol 2021; 18:1867-1881. [PMID: 33522404 PMCID: PMC8583180 DOI: 10.1080/15476286.2021.1874717] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 01/06/2021] [Accepted: 01/07/2021] [Indexed: 11/13/2022] Open
Abstract
While haloarchaea are highly resistant to oxidative stress, a comprehensive understanding of the processes regulating this remarkable response is lacking. Oxidative stress-responsive small non-coding RNAs (sRNAs) have been reported in the model archaeon, Haloferax volc anii, but targets and mechanisms have not been elucidated. Using a combination of high throughput and reverse molecular genetic approaches, we elucidated the functional role of the most up-regulated intergenic sRNA during oxidative stress in H. volcanii, named Small RNA in Haloferax Oxidative Stress (SHOxi). SHOxi was predicted to form a stable secondary structure with a conserved stem-loop region as the potential binding site for trans-targets. NAD-dependent malic enzyme mRNA, identified as a putative target of SHOxi, interacted directly with a putative 'seed' region within the predicted stem loop of SHOxi. Malic enzyme catalyzes the oxidative decarboxylation of malate into pyruvate using NAD+ as a cofactor. The destabilization of malic enzyme mRNA, and the decrease in the NAD+/NADH ratio, resulting from the direct RNA-RNA interaction between SHOxi and its trans-target was essential for the survival of H. volcanii to oxidative stress. These findings indicate that SHOxi likely regulates redox homoeostasis during oxidative stress by the post-transcriptional destabilization of malic enzyme mRNA. SHOxi-mediated regulation provides evidence that the fine-tuning of metabolic cofactors could be a core strategy to mitigate damage from oxidative stress and confer resistance. This study is the first to establish the regulatory effects of sRNAs on mRNAs during the oxidative stress response in Archaea.
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Affiliation(s)
| | - Rahul Reddy
- Department of Biology, The Johns Hopkins University, Baltimore, Maryland, USA
| | | | - Sara Debic
- Department of Biology, The Johns Hopkins University, Baltimore, Maryland, USA
| | - Jocelyne DiRuggiero
- Department of Biology, The Johns Hopkins University, Baltimore, Maryland, USA
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5
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Nayak T, Sengupta I, Dhal PK. A new era of radiation resistance bacteria in bioremediation and production of bioactive compounds with therapeutic potential and other aspects: An in-perspective review. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2021; 237:106696. [PMID: 34265519 DOI: 10.1016/j.jenvrad.2021.106696] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 06/29/2021] [Accepted: 07/01/2021] [Indexed: 06/13/2023]
Abstract
Microorganisms that survive in extreme environmental conditions are known as 'extremophiles'. Recently, extremophiles draw an impression in biotechnology/pharmaceutical researches/industries because of their novel molecules, known as 'extremolytes'. The intriguing phenomenon of microbial radiation resistance probably arose independently throughout their evolution of selective pressures (e.g. UV, X-ray, Gamma radiation etc.). Radiation produces multiple types of damage/oxidation to nucleic acids, proteins and other crucial cellular components. Most of the literature on microbial radiation resistance is based on acute γ-irradiation experiments performed in the laboratory, typically involving pure cultures isolation and their application on bioremediation/therapeutic field. There is much less information other than bioremediation and therapeutic application of such promising microbes we called as 'new era'. Here we discus origin and diversity of radiation resistance bacteria as well as selective mechanisms by which microorganisms can sustain in radiation rich environment. Potential uses of these radiations resistant microbes in the field of bioremediation, bioactive compounds and therapeutic industry. Last but not the least, which is the new aspect of radiation resistance microbes. Our review suggest that resistance to chronic radiation is not limited to rare specialized strains from extreme environments, but can occur among common microbial taxa, perhaps due to overlap molecular mechanisms of resistance to radiation and other stressors. These stress tolerance potential make them potential for radionuclides remediation, their extremolytes can be useful as anti-oxidant and anti-proliferative agents. In current scenario they can be useful in various fields from natural dye synthesis to nanoparticles production and anti-cancer treatment.
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Affiliation(s)
- Tilak Nayak
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, 700032, India.
| | - Indraneel Sengupta
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, 700032, India.
| | - Paltu Kumar Dhal
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, 700032, India.
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6
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Shukla SK, Sharma AK, Bajaj S, Yashavarddhan MH. Radiation proteome: a clue to protection, carcinogenesis, and drug development. Drug Discov Today 2020; 26:525-531. [PMID: 33137481 DOI: 10.1016/j.drudis.2020.10.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 09/29/2020] [Accepted: 10/26/2020] [Indexed: 02/04/2023]
Affiliation(s)
- Sandeep Kumar Shukla
- Institute of Nuclear Medicine and Allied Sciences, Defence Research and Development Organization, Lucknow road, Timarpur, Delhi, 110054, India.
| | - Ajay Kumar Sharma
- Institute of Nuclear Medicine and Allied Sciences, Defence Research and Development Organization, Lucknow road, Timarpur, Delhi, 110054, India
| | - Sania Bajaj
- Institute of Nuclear Medicine and Allied Sciences, Defence Research and Development Organization, Lucknow road, Timarpur, Delhi, 110054, India
| | - M H Yashavarddhan
- Defence Institute of Physiology and Allied Sciences, Defence Research and Development Organization, Lucknow road, Timarpur, Delhi, 110054, India
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7
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Jeong SW, Choi YJ. Extremophilic Microorganisms for the Treatment of Toxic Pollutants in the Environment. Molecules 2020; 25:E4916. [PMID: 33114255 PMCID: PMC7660605 DOI: 10.3390/molecules25214916] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 10/20/2020] [Accepted: 10/23/2020] [Indexed: 12/13/2022] Open
Abstract
As concerns about the substantial effect of various hazardous toxic pollutants on the environment and public health are increasing, the development of effective and sustainable treatment methods is urgently needed. In particular, the remediation of toxic components such as radioactive waste, toxic heavy metals, and other harmful substances under extreme conditions is quite difficult due to their restricted accessibility. Thus, novel treatment methods for the removal of toxic pollutants using extremophilic microorganisms that can thrive under extreme conditions have been investigated during the past several decades. In this review, recent trends in bioremediation using extremophilic microorganisms and related approaches to develop them are reviewed, with relevant examples and perspectives.
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Affiliation(s)
| | - Yong Jun Choi
- School of Environmental Engineering, University of Seoul, Seoul 02504, Korea;
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8
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Romsdahl J, Blachowicz A, Chiang YM, Venkateswaran K, Wang CCC. Metabolomic Analysis of Aspergillus niger Isolated From the International Space Station Reveals Enhanced Production Levels of the Antioxidant Pyranonigrin A. Front Microbiol 2020; 11:931. [PMID: 32670208 PMCID: PMC7326050 DOI: 10.3389/fmicb.2020.00931] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 04/20/2020] [Indexed: 11/13/2022] Open
Abstract
Secondary metabolite (SM) production in Aspergillus niger JSC-093350089, isolated from the International Space Station (ISS), is reported, along with a comparison to the experimentally established strain ATCC 1015. The analysis revealed enhanced production levels of naphtho-γ-pyrones and therapeutically relevant SMs, including bicoumanigrin A, aurasperones A and B, and the antioxidant pyranonigrin A. Genetic variants that may be responsible for increased SM production levels in JSC-093350089 were identified. These findings include INDELs within the predicted promoter region of flbA, which encodes a developmental regulator that modulates pyranonigrin A production via regulation of Fum21. The pyranonigrin A biosynthetic gene cluster was confirmed in A. niger, which revealed the involvement of a previously undescribed gene, pyrE, in its biosynthesis. UVC sensitivity assays enabled characterization of pyranonigrin A as a UV resistance agent in the ISS isolate.
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Affiliation(s)
- Jillian Romsdahl
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Adriana Blachowicz
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States.,Biotechnology and Planetary Protection Group, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States
| | - Yi-Ming Chiang
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Kasthuri Venkateswaran
- Biotechnology and Planetary Protection Group, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States
| | - Clay C C Wang
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States.,Department of Chemistry, Dornsife College of Letters, Arts, and Sciences, University of Southern California, Los Angeles, CA, United States
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9
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Buda DM, Bulzu PA, Barbu-Tudoran L, Porfire A, Pătraș L, Sesărman A, Tripon S, Șenilă M, Ionescu MI, Banciu HL. Physiological response to silver toxicity in the extremely halophilic archaeon Halomicrobium mukohataei. FEMS Microbiol Lett 2019; 366:5632106. [DOI: 10.1093/femsle/fnz231] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Accepted: 11/18/2019] [Indexed: 12/29/2022] Open
Abstract
ABSTRACTAdaptive strategies responsible for heavy metal tolerance were explored in the extremely halophilic archaeon Halomicrobium mukohataei DSM 12286. The tested strain was seemingly able to overcome silver-induced oxidative stress (assessed by malondialdehyde quantification, catalase assay and total antioxidant capacity measurement) mainly through non-enzymatic antioxidants. Energy dispersive spectrometry analysis illustrated the presence of colloidal silver in Hmc. mukohataei cultures exposed to AgNO3. Bright-field and transmission electron microscopy images, as well as dynamic light scattering analysis, demonstrated the presence of intracellular nanoparticles, mostly spherical, within a size range of 20–100 nm. As determined by the zeta potential measurement, the biosynthesized nanoparticles were highly stable, with a negative surface charge. Our research is a first attempt in the systematic study of the oxidative stress and intracellular silver nanoparticle accumulation, generated by exposure to silver ions, in members of Halobacteria class, thus broadening our knowledge on mechanisms supporting heavy metal tolerance of microbial cells living under saline conditions.
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Affiliation(s)
- Doriana-Mădălina Buda
- Department of Molecular Biology and Biotechnology, Faculty of Biology and Geology, Babes-Bolyai University, 5-7 Clinicilor Street, 400006 Cluj-Napoca, Romania
| | - Paul-Adrian Bulzu
- Department of Molecular Biology and Biotechnology, Faculty of Biology and Geology, Babes-Bolyai University, 5-7 Clinicilor Street, 400006 Cluj-Napoca, Romania
- Molecular Biology Centre, Interdisciplinary Research Institute on Bio-Nano-Sciences, Babes-Bolyai University, 42 Treboniu Laurian Street, 400271 Cluj-Napoca, Romania
| | - Lucian Barbu-Tudoran
- National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donath Street, 400293 Cluj-Napoca, Romania
- Electron Microscopy Center, Babeş-Bolyai University, 5-7 Clinicilor Street, 400006 Cluj-Napoca, Romania
| | - Alina Porfire
- Department of Pharmaceutical Technology and Biopharmaceutics, Faculty of Farmacy, University of Medicine and Pharmacy 'Iuliu Hatieganu', 41 Victor Babes Street, 400012 Cluj-Napoca, Romania
| | - Laura Pătraș
- Department of Molecular Biology and Biotechnology, Faculty of Biology and Geology, Babes-Bolyai University, 5-7 Clinicilor Street, 400006 Cluj-Napoca, Romania
- Molecular Biology Centre, Interdisciplinary Research Institute on Bio-Nano-Sciences, Babes-Bolyai University, 42 Treboniu Laurian Street, 400271 Cluj-Napoca, Romania
| | - Alina Sesărman
- Department of Molecular Biology and Biotechnology, Faculty of Biology and Geology, Babes-Bolyai University, 5-7 Clinicilor Street, 400006 Cluj-Napoca, Romania
- Molecular Biology Centre, Interdisciplinary Research Institute on Bio-Nano-Sciences, Babes-Bolyai University, 42 Treboniu Laurian Street, 400271 Cluj-Napoca, Romania
| | - Septimiu Tripon
- National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donath Street, 400293 Cluj-Napoca, Romania
- Electron Microscopy Center, Babeş-Bolyai University, 5-7 Clinicilor Street, 400006 Cluj-Napoca, Romania
| | - Marin Șenilă
- INCDO-INOE 2000, Research Institute for Analytical Instrumentation, 67 Donath Street, 400293 Cluj-Napoca, Romania
| | - Mihaela Ileana Ionescu
- Department of Microbiology, University of Medicine and Pharmacy 'Iuliu Hatieganu', 6 Louis Pasteur Street, 400349 Cluj-Napoca, Romania
| | - Horia Leonard Banciu
- Department of Molecular Biology and Biotechnology, Faculty of Biology and Geology, Babes-Bolyai University, 5-7 Clinicilor Street, 400006 Cluj-Napoca, Romania
- Center for Systems Biology, Biodiversity, and Bioresources, Babes-Bolyai University, 5-7 Clinicilor Street, 400006 Cluj-Napoca, Romania
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10
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Ogwu MC, Srinivasan S, Dong K, Ramasamy D, Waldman B, Adams JM. Community Ecology of Deinococcus in Irradiated Soil. MICROBIAL ECOLOGY 2019; 78:855-872. [PMID: 30980101 DOI: 10.1007/s00248-019-01343-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 02/12/2019] [Indexed: 05/24/2023]
Abstract
Deinococcus is a genus of soil bacteria known for radiation resistance. However, the effects of radiation exposure on its community structure are unknown. We exposed soil to three levels of gamma radiation, 0.1 kGy/h (low), 1 kGy/h (medium), and 3 kGy/h (high), once a week for 6 weeks and then extracted soil DNA for 16S rRNA amplicon sequencing. We found the following: (1) Increasing radiation dose produced a major increase in relative abundance of Deinococcus, reaching ~ 80% of reads at the highest doses. Differing abundances of the various Deinococcus species in relation to exposure levels indicate distinct "radiation niches." At 3 kGy/h, a single OTU identified as D. ficus overwhelmingly dominated the mesocosms. (2) Corresponding published genome data show that the dominant species at 3 kGy/h, D. ficus, has a larger and more complex genome than other Deinococcus species with a greater proportion of genes related to DNA and nucleotide metabolism, cell wall, membrane, and envelope biogenesis as well as more cell cycle control, cell division, and chromosome partitioning-related genes. Deinococcus ficus also has a higher guanine-cytosine ratio than most other Deinococcus. These features may be linked to genome stability and may explain its greater abundance in this apparently competitive system, under high-radiation exposures. (3) Genomic analysis suggests that Deinococcus, including D. ficus, are capable of utilizing diverse carbon sources derived from both microbial cells killed by the radiation (including C5-C12-containing compounds, like arabinose, lactose, N-acetyl-D-glucosamine) and plant-derived organic matter in the soil (e.g., cellulose and hemicellulose). (4) Overall, based on its metagenome, even the most highly irradiated (3 kGy/h) soil possesses a wide range of the activities necessary for a functional soil system. Future studies may consider the resilience and sustainability of such soils in a high-radiation environment.
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Affiliation(s)
- Matthew Chidozie Ogwu
- School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
- Department of Plant Biology and Biotechnology, University of Benin, PMB 1154, Ugbowo, Benin City, Edo State, Nigeria
| | - Sathiyaraj Srinivasan
- Department of Bio and Environmental Technology, Division of Environmental and Life Science, College of Natural Science, Seoul Women's University, 623 Hwarangno, Nowon-gu, Seoul, 139-774, Republic of Korea
| | - Ke Dong
- Department of Life Sciences, Kyonggi University, Suwon, 443-760, Republic of Korea
| | - Dhamodharan Ramasamy
- School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Bruce Waldman
- School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
- Department of Integrative Biology, Oklahoma State University, 501 Life Sciences West, Stillwater, OK, 74078, USA.
| | - Jonathan M Adams
- School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing, 210023, Qixia District, Jiangsu Province, People's Republic of China.
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11
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Shuryak I, Tkavc R, Matrosova VY, Volpe RP, Grichenko O, Klimenkova P, Conze IH, Balygina IA, Gaidamakova EK, Daly MJ. Chronic gamma radiation resistance in fungi correlates with resistance to chromium and elevated temperatures, but not with resistance to acute irradiation. Sci Rep 2019; 9:11361. [PMID: 31388021 PMCID: PMC6684587 DOI: 10.1038/s41598-019-47007-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 06/10/2019] [Indexed: 02/07/2023] Open
Abstract
Exposure to chronic ionizing radiation (CIR) from nuclear power plant accidents, acts of terrorism, and space exploration poses serious threats to humans. Fungi are a group of highly radiation-resistant eukaryotes, and an understanding of fungal CIR resistance mechanisms holds the prospect of protecting humans. We compared the abilities of 95 wild-type yeast and dimorphic fungal isolates, representing diverse Ascomycota and Basidiomycota, to resist exposure to five environmentally-relevant stressors: CIR (long-duration growth under 36 Gy/h) and acute (10 kGy/h) ionizing radiation (IR), heavy metals (chromium, mercury), elevated temperature (up to 50 °C), and low pH (2.3). To quantify associations between resistances to CIR and these other stressors, we used correlation analysis, logistic regression with multi-model inference, and customized machine learning. The results suggest that resistance to acute IR in fungi is not strongly correlated with the ability of a given fungal isolate to grow under CIR. Instead, the strongest predictors of CIR resistance in fungi were resistance to chromium (III) and to elevated temperature. These results suggest fundamental differences between the mechanisms of resistance to chronic and acute radiation. Convergent evolution towards radioresistance among genetically distinct groups of organisms is considered here.
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Affiliation(s)
- Igor Shuryak
- Center for Radiological Research, Columbia University Irving Medical Center, New York, NY, USA.
| | - Rok Tkavc
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA
| | - Vera Y Matrosova
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Robert P Volpe
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Olga Grichenko
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Polina Klimenkova
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Isabel H Conze
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA
- Department of Biology, University of Bielefeld, Bielefeld, Germany
| | - Irina A Balygina
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA
- Institute of Medicine and Psychology, Novosibirsk State University, Novosibirsk, Russia
| | - Elena K Gaidamakova
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Michael J Daly
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA
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12
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Shuryak I. Review of microbial resistance to chronic ionizing radiation exposure under environmental conditions. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2019; 196:50-63. [PMID: 30388428 DOI: 10.1016/j.jenvrad.2018.10.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 10/21/2018] [Indexed: 06/08/2023]
Abstract
Ionizing radiation (IR) produces multiple types of damage to nucleic acids, proteins and other crucial cellular components. Nevertheless, various microorganisms from phylogenetically distant taxa (bacteria, archaea, fungi) can resist IR levels many orders of magnitude above natural background. This intriguing phenomenon of radioresistance probably arose independently many times throughout evolution as a byproduct of selective pressures from other stresses (e.g. desiccation, UV radiation, chemical oxidants). Most of the literature on microbial radioresistance is based on acute γ-irradiation experiments performed in the laboratory, typically involving pure cultures grown under near-optimal conditions. There is much less information about the upper limits of radioresistance in the field, such as in radioactively-contaminated areas, where several radiation types (e.g. α and β, as well as γ) and other stressors (e.g. non-optimal temperature and nutrient levels, toxic chemicals, interspecific competition) act over multiple generations. Here we discuss several examples of radioresistant microbes isolated from extremely radioactive locations (e.g. Chernobyl and Mayak nuclear plant sites) and estimate the radiation dose rates they were able to tolerate. Some of these organisms (e.g. the fungus Cladosporium cladosporioides, the cyanobacterium Geitlerinema amphibium) are widely-distributed and colonize a variety of habitats. These examples suggest that resistance to chronic IR and chemical contamination is not limited to rare specialized strains from extreme environments, but can occur among common microbial taxa, perhaps due to overlap between mechanisms of resistance to IR and other stressors.
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Affiliation(s)
- Igor Shuryak
- Center for Radiological Research, Columbia University, 630 West 168(th) street, VC-11-234/5, New York, NY, 10032, USA.
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13
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Transcriptional Landscape and Regulatory Roles of Small Noncoding RNAs in the Oxidative Stress Response of the Haloarchaeon Haloferax volcanii. J Bacteriol 2018; 200:JB.00779-17. [PMID: 29463600 PMCID: PMC5892119 DOI: 10.1128/jb.00779-17] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Accepted: 02/02/2018] [Indexed: 01/08/2023] Open
Abstract
Haloarchaea in their natural environment are exposed to hypersalinity, intense solar radiation, and desiccation, all of which generate high levels of oxidative stress. Previous work has shown that haloarchaea are an order of magnitude more resistant to oxidative stress than most mesophilic organisms. Despite this resistance, the pathways haloarchaea use to respond to oxidative stress damage are similar to those of nonresistant organisms, suggesting that regulatory processes might be key to their robustness. Recently, small regulatory noncoding RNAs (sRNAs) were discovered in Archaea under a variety of environmental conditions. We report here the transcriptional landscape and functional roles of sRNAs in the regulation of the oxidative stress response of the model haloarchaeon Haloferax volcanii. Thousands of sRNAs, both intergenic and antisense, were discovered using strand-specific sRNA sequencing (sRNA-seq), comprising 25 to 30% of the total transcriptome under no-challenge and oxidative stress conditions, respectively. We identified hundreds of differentially expressed sRNAs in response to hydrogen peroxide-induced oxidative stress in H. volcanii. The targets of a group of antisense sRNAs decreased in expression when these sRNAs were upregulated, suggesting that sRNAs are potentially playing a negative regulatory role on mRNA targets at the transcript level. Target enrichment of these antisense sRNAs included mRNAs involved in transposon mobility, chemotaxis signaling, peptidase activity, and transcription factors. IMPORTANCE While a substantial body of experimental work has been done to uncover the functions of small regulatory noncoding RNAs (sRNAs) in gene regulation in Bacteria and Eukarya, the functional roles of sRNAs in Archaea are still poorly understood. This study is the first to establish the regulatory effects of sRNAs on mRNAs during the oxidative stress response in the haloarchaeon Haloferax volcanii. Our work demonstrates that common principles for the response to a major cellular stress exist across the 3 domains of life while uncovering pathways that might be specific to the Archaea. This work also underscores the relevance of sRNAs in adaptation to extreme environmental conditions.
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Kumar A, Alam A, Tripathi D, Rani M, Khatoon H, Pandey S, Ehtesham NZ, Hasnain SE. Protein adaptations in extremophiles: An insight into extremophilic connection of mycobacterial proteome. Semin Cell Dev Biol 2018; 84:147-157. [PMID: 29331642 DOI: 10.1016/j.semcdb.2018.01.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Revised: 09/01/2017] [Accepted: 01/09/2018] [Indexed: 02/02/2023]
Abstract
The biological paradox about how extremophiles persist at extreme ecological conditions throws a fascinating picture of the enormous potential of a single cell to adapt to homeostatic conditions in order to propagate. Unicellular organisms face challenges from both environmental factors and the ecological niche provided by the host tissue. Although the existence of extremophiles and their physiological properties were known for a long time, availability of whole genome sequence has catapulted the study on mechanisms of adaptation and the underlying principles that have enabled these unique organisms to withstand evolutionary and environmental pressures. Comparative genomics has shown that extremophiles possess the unique set of genes and proteins that empower them with biochemical machinery necessary to thrive in extreme environments. The presence of these proteins safeguards the cell against a wide array of extreme conditions such as temperature, pressure, radiations, chemicals, drugs etc. An insight into these adaptive mechanisms in extremophiles may help us to devise strategies to alter the genes and proteins that may have therapeutic potential and commercial value. Here we present an overview of the various adaptations in extremophiles. We also try to explain how mycobacterium channelizes its proteome to survive in stress conditions posed by host immune system.
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Affiliation(s)
- Ashutosh Kumar
- Molecular Infection and Functional Biology Lab, Kusuma School of Biological Sciences, Indian Institute of Technology-Delhi, New Delhi, India
| | - Anwar Alam
- Molecular Infection and Functional Biology Lab, Kusuma School of Biological Sciences, Indian Institute of Technology-Delhi, New Delhi, India
| | - Deeksha Tripathi
- Department of Microbiology, Central University of Rajasthan, Bandar Sindri, Ajmer, Rajasthan, India
| | - Mamta Rani
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology-Delhi, New Delhi, India
| | - Hafeeza Khatoon
- Molecular Infection and Functional Biology Lab, Kusuma School of Biological Sciences, Indian Institute of Technology-Delhi, New Delhi, India
| | - Saurabh Pandey
- National Institute of Pathology, Safdarjang Hospital Campus, New Delhi, India
| | - Nasreen Z Ehtesham
- National Institute of Pathology, Safdarjang Hospital Campus, New Delhi, India
| | - Seyed E Hasnain
- Molecular Infection and Functional Biology Lab, Kusuma School of Biological Sciences, Indian Institute of Technology-Delhi, New Delhi, India; JH-Institute of Molecular Medicine, Hamdard Nagar, New Delhi, India; Dr Reddy's Institute of Life Sciences, University of Hyderabad Campus, Hyderabad, India.
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15
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Stelmach KB, Neveu M, Vick-Majors TJ, Mickol RL, Chou L, Webster KD, Tilley M, Zacchei F, Escudero C, Flores Martinez CL, Labrado A, Fernández EJG. Secondary Electrons as an Energy Source for Life. ASTROBIOLOGY 2018; 18:73-85. [PMID: 29314901 DOI: 10.1089/ast.2016.1510] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Life on Earth is found in a wide range of environments as long as the basic requirements of a liquid solvent, a nutrient source, and free energy are met. Previous hypotheses have speculated how extraterrestrial microbial life may function, among them that particle radiation might power living cells indirectly through radiolytic products. On Earth, so-called electrophilic organisms can harness electron flow from an extracellular cathode to build biomolecules. Here, we describe two hypothetical mechanisms, termed "direct electrophy" and "indirect electrophy" or "fluorosynthesis," by which organisms could harness extracellular free electrons to synthesize organic matter, thus expanding the ensemble of potential habitats in which extraterrestrial organisms might be found in the Solar System and beyond. The first mechanism involves the direct flow of secondary electrons from particle radiation to a microbial cell to power the organism. The second involves the indirect utilization of impinging secondary electrons and a fluorescing molecule, either biotic or abiotic in origin, to drive photosynthesis. Both mechanisms involve the attenuation of an incoming particle's energy to create low-energy secondary electrons. The validity of the hypotheses is assessed through simple calculations showing the biomass density attainable from the energy supplied. Also discussed are potential survival strategies that could be used by organisms living in possible habitats with a plentiful supply of secondary electrons, such as near the surface of an icy moon. While we acknowledge that the only definitive test for the hypothesis is to collect specimens, we also describe experiments or terrestrial observations that could support or nullify the hypotheses. Key Words: Radiation-Electrophiles-Subsurface life. Astrobiology 18, 73-85.
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Affiliation(s)
- Kamil B Stelmach
- 1 Department of Chemistry and Biochemistry, George Mason University , Fairfax, Virginia, USA
| | - Marc Neveu
- 2 School of Earth and Space Exploration, Arizona State University , Tempe, Arizona, USA
| | - Trista J Vick-Majors
- 3 Department of Land Resources and Environmental Sciences, Montana State University , Bozeman, Montana, USA
- 4 Département des sciences biologiques, Université du Québec à Montréal , Montréal, Canada
| | - Rebecca L Mickol
- 5 Arkansas Center for Space and Planetary Sciences, University of Arkansas , Fayetteville, Arkansas, USA
| | - Luoth Chou
- 6 Department of Earth and Environmental Sciences, University of Illinois at Chicago , Chicago, Illinois, USA
| | - Kevin D Webster
- 7 Department of Ecology and Evolutionary Biology, University of Arizona , Tucson, Arizona, USA
- 8 School of Natural Resources and the Environment, University of Arizona , Tucson, Arizona, USA
| | - Matt Tilley
- 9 Department of Earth and Space Sciences, University of Washington , Seattle, Washington, USA
| | - Federica Zacchei
- 10 Instituut voor Sterrenkunde, University of Leuven , Leuven, Belgium
| | | | | | - Amanda Labrado
- 13 Department of Geosciences, The Pennsylvania State University , University Park, Pennsylvania, USA
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16
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Martinez-Pastor M, Lancaster WA, Tonner PD, Adams MWW, Schmid AK. A transcription network of interlocking positive feedback loops maintains intracellular iron balance in archaea. Nucleic Acids Res 2017; 45:9990-10001. [PMID: 28973467 PMCID: PMC5737653 DOI: 10.1093/nar/gkx662] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 07/18/2017] [Indexed: 02/06/2023] Open
Abstract
Iron is required for key metabolic processes but is toxic in excess. This circumstance forces organisms across the tree of life to tightly regulate iron homeostasis. In hypersaline lakes dominated by archaeal species, iron levels are extremely low and subject to environmental change; however, mechanisms regulating iron homeostasis in archaea remain unclear. In previous work, we demonstrated that two transcription factors (TFs), Idr1 and Idr2, collaboratively regulate aspects of iron homeostasis in the model species Halobacterium salinarum. Here we show that Idr1 and Idr2 are part of an extended regulatory network of four TFs of the bacterial DtxR family that maintains intracellular iron balance. We demonstrate that each TF directly regulates at least one of the other DtxR TFs at the level of transcription. Dynamical modeling revealed interlocking positive feedback loop architecture, which exhibits bistable or oscillatory network dynamics depending on iron availability. TF knockout mutant phenotypes are consistent with model predictions. Together, our results support that this network regulates iron homeostasis despite variation in extracellular iron levels, consistent with dynamical properties of interlocking feedback architecture in eukaryotes. These results suggest that archaea use bacterial-type TFs in a eukaryotic regulatory network topology to adapt to harsh environments.
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Affiliation(s)
| | - W Andrew Lancaster
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Peter D Tonner
- Computational Biology and Bioinformatics Graduate Program, Duke University, Durham, NC 27708, USA
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Amy K Schmid
- Department of Biology, Duke University, Durham, NC 27708, USA.,Computational Biology and Bioinformatics Graduate Program, Duke University, Durham, NC 27708, USA.,Center for Genomics and Computational Biology, Duke University, Durham, NC 27708, USA
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17
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Across the tree of life, radiation resistance is governed by antioxidant Mn 2+, gauged by paramagnetic resonance. Proc Natl Acad Sci U S A 2017; 114:E9253-E9260. [PMID: 29042516 PMCID: PMC5676931 DOI: 10.1073/pnas.1713608114] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Despite concerted functional genomic efforts to understand the complex phenotype of ionizing radiation (IR) resistance, a genome sequence cannot predict whether a cell is IR-resistant or not. Instead, we report that absorption-display electron paramagnetic resonance (EPR) spectroscopy of nonirradiated cells is highly diagnostic of IR survival and repair efficiency of DNA double-strand breaks (DSBs) caused by exposure to gamma radiation across archaea, bacteria, and eukaryotes, including fungi and human cells. IR-resistant cells, which are efficient at DSB repair, contain a high cellular content of manganous ions (Mn2+) in high-symmetry (H) antioxidant complexes with small metabolites (e.g., orthophosphate, peptides), which exhibit narrow EPR signals (small zero-field splitting). In contrast, Mn2+ ions in IR-sensitive cells, which are inefficient at DSB repair, exist largely as low-symmetry (L) complexes with substantially broadened spectra seen with enzymes and strongly chelating ligands. The fraction of cellular Mn2+ present as H-complexes (H-Mn2+), as measured by EPR of live, nonirradiated Mn-replete cells, is now the strongest known gauge of biological IR resistance between and within organisms representing all three domains of life: Antioxidant H-Mn2+ complexes, not antioxidant enzymes (e.g., Mn superoxide dismutase), govern IR survival. As the pool of intracellular metabolites needed to form H-Mn2+ complexes depends on the nutritional status of the cell, we conclude that IR resistance is predominantly a metabolic phenomenon. In a cross-kingdom analysis, the vast differences in taxonomic classification, genome size, and radioresistance between cell types studied here support that IR resistance is not controlled by the repertoire of DNA repair and antioxidant enzymes.
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18
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Jones DL, Baxter BK. DNA Repair and Photoprotection: Mechanisms of Overcoming Environmental Ultraviolet Radiation Exposure in Halophilic Archaea. Front Microbiol 2017; 8:1882. [PMID: 29033920 PMCID: PMC5626843 DOI: 10.3389/fmicb.2017.01882] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 09/14/2017] [Indexed: 12/31/2022] Open
Abstract
Halophilic archaea push the limits of life at several extremes. In particular, they are noted for their biochemical strategies in dealing with osmotic stress, low water activity and cycles of desiccation in their hypersaline environments. Another feature common to their habitats is intense ultraviolet (UV) radiation, which is a challenge that microorganisms must overcome. The consequences of high UV exposure include DNA lesions arising directly from bond rearrangement of adjacent bipyrimidines, or indirectly from oxidative damage, which may ultimately result in mutation and cell death. As such, these microorganisms have evolved a number of strategies to navigate the threat of DNA damage, which we differentiate into two categories: DNA repair and photoprotection. Photoprotection encompasses damage avoidance strategies that serve as a "first line of defense," and in halophilic archaea include pigmentation by carotenoids, mechanisms of oxidative damage avoidance, polyploidy, and genomic signatures that make DNA less susceptible to photodamage. Photolesions that do arise are addressed by a number of DNA repair mechanisms that halophilic archaea efficiently utilize, which include photoreactivation, nucleotide excision repair, base excision repair, and homologous recombination. This review seeks to place DNA damage, repair, and photoprotection in the context of halophilic archaea and the solar radiation of their hypersaline environments. We also provide new insight into the breadth of strategies and how they may work together to produce remarkable UV-resistance for these microorganisms.
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Affiliation(s)
| | - Bonnie K. Baxter
- Department of Biology, Great Salt Lake Institute, Westminster College, Salt Lake City, UT, United States
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19
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Jung KW, Lim S, Bahn YS. Microbial radiation-resistance mechanisms. J Microbiol 2017; 55:499-507. [PMID: 28664512 DOI: 10.1007/s12275-017-7242-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 06/19/2017] [Indexed: 11/28/2022]
Abstract
Organisms living in extreme environments have evolved a wide range of survival strategies by changing biochemical and physiological features depending on their biological niches. Interestingly, organisms exhibiting high radiation resistance have been discovered in the three domains of life (Bacteria, Archaea, and Eukarya), even though a naturally radiationintensive environment has not been found. To counteract the deleterious effects caused by radiation exposure, radiation- resistant organisms employ a series of defensive systems, such as changes in intracellular cation concentration, excellent DNA repair systems, and efficient enzymatic and non-enzymatic antioxidant systems. Here, we overview past and recent findings about radiation-resistance mechanisms in the three domains of life for potential usage of such radiationresistant microbes in the biotechnology industry.
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Affiliation(s)
- Kwang-Woo Jung
- Research Division for Biotechnology, Korea Atomic Energy Research Institute, Jeongeup, 56212, Republic of Korea
| | - Sangyong Lim
- Research Division for Biotechnology, Korea Atomic Energy Research Institute, Jeongeup, 56212, Republic of Korea.
| | - Yong-Sun Bahn
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, Republic of Korea.
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20
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Shirsalimian MS, Amoozegar MA, Sepahy AA, Kalantar SM, Dabbagh R. Isolation of extremely halophilic Archaea from a saline river in the Lut Desert of Iran, moderately resistant to desiccation and gamma radiation. Microbiology (Reading) 2017. [DOI: 10.1134/s0026261717030158] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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21
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Ranawat P, Rawat S. Radiation resistance in thermophiles: mechanisms and applications. World J Microbiol Biotechnol 2017; 33:112. [DOI: 10.1007/s11274-017-2279-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 04/26/2017] [Indexed: 12/28/2022]
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22
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Ranawat P, Rawat S. Stress response physiology of thermophiles. Arch Microbiol 2017; 199:391-414. [DOI: 10.1007/s00203-016-1331-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 12/07/2016] [Accepted: 12/16/2016] [Indexed: 10/20/2022]
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23
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Unraveling Fungal Radiation Resistance Regulatory Networks through the Genome-Wide Transcriptome and Genetic Analyses of Cryptococcus neoformans. mBio 2016; 7:mBio.01483-16. [PMID: 27899501 PMCID: PMC5137497 DOI: 10.1128/mbio.01483-16] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The basidiomycetous fungus Cryptococcus neoformans has been known to be highly radiation resistant and has been found in fatal radioactive environments such as the damaged nuclear reactor at Chernobyl. To elucidate the mechanisms underlying the radiation resistance phenotype of C. neoformans, we identified genes affected by gamma radiation through genome-wide transcriptome analysis and characterized their functions. We found that genes involved in DNA damage repair systems were upregulated in response to gamma radiation. Particularly, deletion of recombinase RAD51 and two DNA-dependent ATPase genes, RAD54 and RDH54, increased cellular susceptibility to both gamma radiation and DNA-damaging agents. A variety of oxidative stress response genes were also upregulated. Among them, sulfiredoxin contributed to gamma radiation resistance in a peroxiredoxin/thioredoxin-independent manner. Furthermore, we found that genes involved in molecular chaperone expression, ubiquitination systems, and autophagy were induced, whereas genes involved in the biosynthesis of proteins and fatty acids/sterols were downregulated. Most importantly, we discovered a number of novel C. neoformans genes, the expression of which was modulated by gamma radiation exposure, and their deletion rendered cells susceptible to gamma radiation exposure, as well as DNA damage insults. Among these genes, we found that a unique transcription factor containing the basic leucine zipper domain, named Bdr1, served as a regulator of the gamma radiation resistance of C. neoformans by controlling expression of DNA repair genes, and its expression was regulated by the evolutionarily conserved DNA damage response protein kinase Rad53. Taken together, the current transcriptome and functional analyses contribute to the understanding of the unique molecular mechanism of the radiation-resistant fungus C. neoformans. Although there are no natural environments under intense radiation, some living organisms have been found to show high radiation resistance. Organisms harboring the ability of radiation resistance have unique regulatory networks to overcome this stress. Cryptococcus neoformans is one of the radiation-resistant fungi and is found in highly radioactive environments. However, it remains elusive how radiation-resistant eukaryotic microorganisms work differentially from radiation-sensitive ones. Here, we performed transcriptome analysis of C. neoformans to explore gene expression profiles after gamma radiation exposure and functionally characterized some of identified radiation resistance genes. Notably, we identified a novel regulator of radiation resistance, named Bdr1 (a bZIP TF for DNA damage response 1), which is a transcription factor (TF) that is not closely homologous to any known TF and is transcriptionally controlled by the Rad53 kinase. Therefore, our work could shed light on understanding not only the radiation response but also the radiation resistance mechanism of C. neoformans.
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Losensky G, Jung K, Urlaub H, Pfeifer F, Fröls S, Lenz C. Shedding light on biofilm formation ofHalobacterium salinarumR1 by SWATH-LC/MS/MS analysis of planktonic and sessile cells. Proteomics 2016; 17. [DOI: 10.1002/pmic.201600111] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 07/30/2016] [Accepted: 09/05/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Gerald Losensky
- Microbiology and Archaea; Department of Biology; Technische Universität Darmstadt; Darmstadt Germany
| | - Klaus Jung
- Institute for Animal Breeding and Genetics; University of Veterinary Medicine Foundation; Hannover Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry Group; Max Planck Institute for Biophysical Chemistry; Göttingen Germany
- Institute of Clinical Chemistry; Bioanalytics; University Medical Center Göttingen; Göttingen Germany
| | - Felicitas Pfeifer
- Microbiology and Archaea; Department of Biology; Technische Universität Darmstadt; Darmstadt Germany
| | - Sabrina Fröls
- Microbiology and Archaea; Department of Biology; Technische Universität Darmstadt; Darmstadt Germany
| | - Christof Lenz
- Bioanalytical Mass Spectrometry Group; Max Planck Institute for Biophysical Chemistry; Göttingen Germany
- Institute of Clinical Chemistry; Bioanalytics; University Medical Center Göttingen; Göttingen Germany
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25
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Barbier E, Lagorce A, Hachemi A, Dutertre M, Gorlas A, Morand L, Saint-Pierre C, Ravanat JL, Douki T, Armengaud J, Gasparutto D, Confalonieri F, Breton J. Oxidative DNA Damage and Repair in the Radioresistant Archaeon Thermococcus gammatolerans. Chem Res Toxicol 2016; 29:1796-1809. [PMID: 27676238 DOI: 10.1021/acs.chemrestox.6b00128] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The hyperthermophilic archaeon Thermococcus gammatolerans can resist huge doses of γ-irradiation, up to 5.0 kGy, without loss of viability. The potential to withstand such harsh conditions is probably due to complementary passive and active mechanisms, including repair of damaged chromosomes. In this work, we documented the formation and repair of oxidative DNA lesions in T. gammatolerans. The basal level of the oxidized nucleoside, 8-oxo-2'-deoxyguanosine (8-oxo-dGuo), was established at 9.2 (± 0.9) 8-oxo-dGuo per 106 nucleosides, a higher level than those usually measured in eukaryotic cells or bacteria. A significant increase in oxidative damage, i.e., up to 24.2 (± 8.0) 8-oxo-dGuo/106 nucleosides, was measured for T. gammatolerans exposed to a 5.0 kGy dose of γ-rays. Surprisingly, the yield of radiation-induced modifications was lower than those previously observed for human cells exposed to doses corresponding to a few grays. One hour after irradiation, 8-oxo-dGuo levels were significantly reduced, indicating an efficient repair. Two putative base excision repair (BER) enzymes, TGAM_1277 and TGAM_1653, were demonstrated both by proteomics and transcriptomics to be present in the cells without exposure to ionizing radiation. Their transcripts were moderately upregulated after gamma irradiation. After heterologous production and purification of these enzymes, biochemical assays based on electrophoresis and MALDI-TOF (matrix-assisted laser desorption ionization-time of flight) mass spectrometry indicated that both have a β-elimination cleavage activity. TGAM_1653 repairs 8-oxo-dGuo, whereas TGAM_1277 is also able to remove lesions affecting pyrimidines (1-[2-deoxy-β-d-erythro-pentofuranosyl]-5-hydroxyhydantoin (5-OH-dHyd) and 1-[2-deoxy-β-d-erythro-pentofuranosyl]-5-hydroxy-5-methylhydantoin (5-OH-5-Me-dHyd)). This work showed that in normal growth conditions or in the presence of a strong oxidative stress, T. gammatolerans has the potential to rapidly reduce the extent of DNA oxidation, with at least these two BER enzymes as bodyguards with distinct substrate ranges.
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Affiliation(s)
- Ewa Barbier
- University of Grenoble Alpes, INAC, LCIB , F-38000 Grenoble, France.,CEA, INAC, SyMMES, F-38000 Grenoble, France
| | - Arnaud Lagorce
- University of Paris-Sud, Institute for Integrative Biology of the Cell (I2BC), Université Paris Saclay, CEA, CNRS, Orsay, France.,University of Perpignan, IHPE - UMR 5244 CNRS/IFREMER/Univ. Montpellier, Montpellier, F-34095, France
| | - Amine Hachemi
- University of Paris-Sud, Institute for Integrative Biology of the Cell (I2BC), Université Paris Saclay, CEA, CNRS, Orsay, France
| | - Murielle Dutertre
- University of Paris-Sud, Institute for Integrative Biology of the Cell (I2BC), Université Paris Saclay, CEA, CNRS, Orsay, France
| | - Aurore Gorlas
- University of Paris-Sud, Institute for Integrative Biology of the Cell (I2BC), Université Paris Saclay, CEA, CNRS, Orsay, France
| | - Lucie Morand
- University of Grenoble Alpes, INAC, LCIB , F-38000 Grenoble, France.,CEA, INAC, SyMMES, F-38000 Grenoble, France
| | - Christine Saint-Pierre
- University of Grenoble Alpes, INAC, LCIB , F-38000 Grenoble, France.,CEA, INAC, SyMMES, F-38000 Grenoble, France
| | - Jean-Luc Ravanat
- University of Grenoble Alpes, INAC, LCIB , F-38000 Grenoble, France.,CEA, INAC, SyMMES, F-38000 Grenoble, France
| | - Thierry Douki
- University of Grenoble Alpes, INAC, LCIB , F-38000 Grenoble, France.,CEA, INAC, SyMMES, F-38000 Grenoble, France
| | - Jean Armengaud
- CEA, DSV-Li2D, Laboratory "Innovative Technologies for Detection and Diagnostics", BP 17171, Bagnols-sur-Cèze, F-30207, France
| | - Didier Gasparutto
- University of Grenoble Alpes, INAC, LCIB , F-38000 Grenoble, France.,CEA, INAC, SyMMES, F-38000 Grenoble, France
| | - Fabrice Confalonieri
- University of Paris-Sud, Institute for Integrative Biology of the Cell (I2BC), Université Paris Saclay, CEA, CNRS, Orsay, France
| | - Jean Breton
- University of Grenoble Alpes, INAC, LCIB , F-38000 Grenoble, France.,CEA, INAC, SyMMES, F-38000 Grenoble, France
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Kellermann MY, Yoshinaga MY, Valentine RC, Wörmer L, Valentine DL. Important roles for membrane lipids in haloarchaeal bioenergetics. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:2940-2956. [PMID: 27565574 DOI: 10.1016/j.bbamem.2016.08.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Revised: 08/11/2016] [Accepted: 08/19/2016] [Indexed: 10/21/2022]
Abstract
Recent advances in lipidomic analysis in combination with various physiological experiments set the stage for deciphering the structure-function of haloarchaeal membrane lipids. Here we focused primarily on changes in lipid composition of Haloferax volcanii, but also performed a comparative analysis with four other haloarchaeal species (Halobacterium salinarum, Halorubrum lacusprofundi, Halorubrum sodomense and Haloplanus natans) all representing distinctive cell morphologies and behaviors (i.e., rod shape vs. pleomorphic behavior). Common to all five haloarchaea, our data reveal an extraordinary high level of menaquinone, reaching up to 72% of the total lipids. This ubiquity suggests that menaquinones may function beyond their ordinary role as electron and proton transporter, acting simultaneously as ion permeability barriers and as powerful shield against oxidative stress. In addition, we aimed at understanding the role of cations interacting with the characteristic negatively charged surface of haloarchaeal membranes. We propose for instance that by bridging the negative charges of adjacent anionic phospholipids, Mg2+ acts as surrogate for cardiolipin, a molecule that is known to control curvature stress of membranes. This study further provides a bioenergetic perspective as to how haloarchaea evolved following oxygenation of Earth's atmosphere. The success of the aerobic lifestyle of haloarchaea includes multiple membrane-based strategies that successfully balance the need for a robust bilayer structure with the need for high rates of electron transport - collectively representing the molecular basis to inhabit hypersaline water bodies around the planet.
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Affiliation(s)
- Matthias Y Kellermann
- Department of Earth Science and Marine Science Institute, University of California, Santa Barbara, CA 93106, USA.
| | - Marcos Y Yoshinaga
- MARUM Center for Marine Environmental Sciences and Department of Geosciences, University of Bremen, Leobener Strasse, D-28359 Bremen, Germany
| | | | - Lars Wörmer
- MARUM Center for Marine Environmental Sciences and Department of Geosciences, University of Bremen, Leobener Strasse, D-28359 Bremen, Germany
| | - David L Valentine
- Department of Earth Science and Marine Science Institute, University of California, Santa Barbara, CA 93106, USA.
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Badri H, Monsieurs P, Coninx I, Nauts R, Wattiez R, Leys N. Temporal Gene Expression of the Cyanobacterium Arthrospira in Response to Gamma Rays. PLoS One 2015; 10:e0135565. [PMID: 26308624 PMCID: PMC4550399 DOI: 10.1371/journal.pone.0135565] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 07/23/2015] [Indexed: 12/16/2022] Open
Abstract
The edible cyanobacterium Arthrospira is resistant to ionising radiation. The cellular mechanisms underlying this radiation resistance are, however, still largely unknown. Therefore, additional molecular analysis was performed to investigate how these cells can escape from, protect against, or repair the radiation damage. Arthrospira cells were shortly exposed to different doses of 60Co gamma rays and the dynamic response was investigated by monitoring its gene expression and cell physiology at different time points after irradiation. The results revealed a fast switch from an active growth state to a kind of 'survival modus' during which the cells put photosynthesis, carbon and nitrogen assimilation on hold and activate pathways for cellular protection, detoxification, and repair. The higher the radiation dose, the more pronounced this global emergency response is expressed. Genes repressed during early response, suggested a reduction of photosystem II and I activity and reduced tricarboxylic acid (TCA) and Calvin-Benson-Bassham (CBB) cycles, combined with an activation of the pentose phosphate pathway (PPP). For reactive oxygen species detoxification and restoration of the redox balance in Arthrospira cells, the results suggested a powerful contribution of the antioxidant molecule glutathione. The repair mechanisms of Arthrospira cells that were immediately switched on, involve mainly proteases for damaged protein removal, single strand DNA repair and restriction modification systems, while recA was not induced. Additionally, the exposed cells showed significant increased expression of arh genes, coding for a novel group of protein of unknown function, also seen in our previous irradiation studies. This observation confirms our hypothesis that arh genes are key elements in radiation resistance of Arthrospira, requiring further investigation. This study provides new insights into phasic response and the cellular pathways involved in the radiation resistance of microbial cells, in particularly for photosynthetic organisms as the cyanobacterium Arthrospira.
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Affiliation(s)
- Hanène Badri
- Expert Groups for Molecular and Cellular Biology and Biosphere Impact Studies, Belgian Nuclear Research Centre SCK•CEN, Mol, Belgium
- Proteomics and Microbiology Group, Research Institute for Biosciences, University of Mons, Mons, Belgium
| | - Pieter Monsieurs
- Expert Groups for Molecular and Cellular Biology and Biosphere Impact Studies, Belgian Nuclear Research Centre SCK•CEN, Mol, Belgium
| | - Ilse Coninx
- Expert Groups for Molecular and Cellular Biology and Biosphere Impact Studies, Belgian Nuclear Research Centre SCK•CEN, Mol, Belgium
| | - Robin Nauts
- Expert Groups for Molecular and Cellular Biology and Biosphere Impact Studies, Belgian Nuclear Research Centre SCK•CEN, Mol, Belgium
| | - Ruddy Wattiez
- Proteomics and Microbiology Group, Research Institute for Biosciences, University of Mons, Mons, Belgium
| | - Natalie Leys
- Expert Groups for Molecular and Cellular Biology and Biosphere Impact Studies, Belgian Nuclear Research Centre SCK•CEN, Mol, Belgium
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Dizdaroglu M, Coskun E, Jaruga P. Measurement of oxidatively induced DNA damage and its repair, by mass spectrometric techniques. Free Radic Res 2015; 49:525-48. [PMID: 25812590 DOI: 10.3109/10715762.2015.1014814] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Oxidatively induced damage caused by free radicals and other DNA-damaging agents generate a plethora of products in the DNA of living organisms. There is mounting evidence for the involvement of this type of damage in the etiology of numerous diseases including carcinogenesis. For a thorough understanding of the mechanisms, cellular repair, and biological consequences of DNA damage, accurate measurement of resulting products must be achieved. There are various analytical techniques, with their own advantages and drawbacks, which can be used for this purpose. Mass spectrometric techniques with isotope dilution, which include gas chromatography (GC) and liquid chromatography (LC), provide structural elucidation of products and ascertain accurate quantification, which are absolutely necessary for reliable measurement. Both gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-mass spectrometry (LC-MS), in single or tandem versions, have been used for the measurement of numerous DNA products such as sugar and base lesions, 8,5'-cyclopurine-2'-deoxynucleosides, base-base tandem lesions, and DNA-protein crosslinks, in vitro and in vivo. This article reviews these techniques and their applications in the measurement of oxidatively induced DNA damage and its repair.
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Affiliation(s)
- M Dizdaroglu
- Biomolecular Measurement Division, National Institute of Standards and Technology , Gaithersburg, MD , USA
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29
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de Groot A, Roche D, Fernandez B, Ludanyi M, Cruveiller S, Pignol D, Vallenet D, Armengaud J, Blanchard L. RNA sequencing and proteogenomics reveal the importance of leaderless mRNAs in the radiation-tolerant bacterium Deinococcus deserti. Genome Biol Evol 2015; 6:932-48. [PMID: 24723731 PMCID: PMC4007540 DOI: 10.1093/gbe/evu069] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Deinococcus deserti is a desiccation- and radiation-tolerant desert bacterium. Differential RNA sequencing (RNA-seq) was performed to explore the specificities of its transcriptome. Strikingly, for 1,174 (60%) mRNAs, the transcription start site was found exactly at (916 cases, 47%) or very close to the translation initiation codon AUG or GUG. Such proportion of leaderless mRNAs, which may resemble ancestral mRNAs, is unprecedented for a bacterial species. Proteomics showed that leaderless mRNAs are efficiently translated in D. deserti. Interestingly, we also found 173 additional transcripts with a 5′-AUG or 5′-GUG that would make them competent for ribosome binding and translation into novel small polypeptides. Fourteen of these are predicted to be leader peptides involved in transcription attenuation. Another 30 correlated with new gene predictions and/or showed conservation with annotated and nonannotated genes in other Deinococcus species, and five of these novel polypeptides were indeed detected by mass spectrometry. The data also allowed reannotation of the start codon position of 257 genes, including several DNA repair genes. Moreover, several novel highly radiation-induced genes were found, and their potential roles are discussed. On the basis of our RNA-seq and proteogenomics data, we propose that translation of many of the novel leaderless transcripts, which may have resulted from single-nucleotide changes and maintained by selective pressure, provides a new explanation for the generation of a cellular pool of small peptides important for protection of proteins against oxidation and thus for radiation/desiccation tolerance and adaptation to harsh environmental conditions.
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Affiliation(s)
- Arjan de Groot
- CEA, DSV, IBEB, Lab Bioénergétique Cellulaire, Saint-Paul-lez-Durance, France
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30
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Badri H, Monsieurs P, Coninx I, Wattiez R, Leys N. Molecular investigation of the radiation resistance of edible cyanobacterium Arthrospira sp. PCC 8005. Microbiologyopen 2015; 4:187-207. [PMID: 25678338 PMCID: PMC4398503 DOI: 10.1002/mbo3.229] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 10/28/2014] [Accepted: 11/10/2014] [Indexed: 01/28/2023] Open
Abstract
The aim of this work was to characterize in detail the response of Arthrospira to ionizing radiation, to better understand its radiation resistance capacity. Live cells of Arthrospira sp. PCC 8005 were irradiated with 60Co gamma rays. This study is the first, showing that Arthrospira is highly tolerant to gamma rays, and can survive at least 6400 Gy (dose rate of 527 Gy h−1), which identified Arthrospira sp. PCC 8005 as a radiation resistant bacterium. Biochemical, including proteomic and transcriptomic, analysis after irradiation with 3200 or 5000 Gy showed a decline in photosystem II quantum yield, reduced carbon fixation, and reduced pigment, lipid, and secondary metabolite synthesis. Transcription of photo-sensing and signaling pathways, and thiol-based antioxidant systems was induced. Transcriptomics did show significant activation of ssDNA repair systems and mobile genetic elements (MGEs) at the RNA level. Surprisingly, the cells did not induce the classical antioxidant or DNA repair systems, such superoxide dismutase (SOD) enzyme and the RecA protein. Arthrospira cells lack the catalase gene and the LexA repressor. Irradiated Arthrospira cells did induce strongly a group of conserved proteins, of which the function in radiation resistance remains to be elucidated, but which are a promising novel routes to be explored. This study revealed the radiation resistance of Arthrospira, and the molecular systems involved, paving the way for its further and better exploitation.
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Affiliation(s)
- Hanène Badri
- Expert Group for Molecular and Cellular Biology, Belgian Nuclear Research Center SCK•CEN, Mol, Belgium.,Proteomics and Microbiology Group, Research Institute for Biosciences, University of Mons, Mons, Belgium
| | - Pieter Monsieurs
- Expert Group for Molecular and Cellular Biology, Belgian Nuclear Research Center SCK•CEN, Mol, Belgium
| | - Ilse Coninx
- Expert Group for Molecular and Cellular Biology, Belgian Nuclear Research Center SCK•CEN, Mol, Belgium
| | - Ruddy Wattiez
- Proteomics and Microbiology Group, Research Institute for Biosciences, University of Mons, Mons, Belgium
| | - Natalie Leys
- Expert Group for Molecular and Cellular Biology, Belgian Nuclear Research Center SCK•CEN, Mol, Belgium
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Baxter BK, Gunde-Cimerman N, Oren A. Salty sisters: The women of halophiles. Front Microbiol 2014; 5:192. [PMID: 24926287 PMCID: PMC4045239 DOI: 10.3389/fmicb.2014.00192] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 04/10/2014] [Indexed: 01/02/2023] Open
Abstract
A history of halophile research reveals the commitment of scientists to uncovering the secrets of the limits of life, in particular life in high salt concentration and under extreme osmotic pressure. During the last 40 years, halophile scientists have indeed made important contributions to extremophile research, and prior international halophiles congresses have documented both the historical and the current work. During this period of salty discoveries, female scientists, in general, have grown in number worldwide. But those who worked in the field when there were small numbers of women sometimes saw their important contributions overshadowed by their male counterparts. Recent studies suggest that modern female scientists experience gender bias in matters such as conference invitations and even representation among full professors. In the field of halophilic microbiology, what is the impact of gender bias? How has the participation of women changed over time? What do women uniquely contribute to this field? What are factors that impact current female scientists to a greater degree? This essay emphasizes the “her story” (not “history”) of halophile discovery.
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Affiliation(s)
- Bonnie K Baxter
- Great Salt Lake Institute, Westminster College Salt Lake City, UT, USA
| | - Nina Gunde-Cimerman
- Molecular Genetics and Microbiology, University of Ljubljana Ljubljana, Slovenia ; Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins Ljubljana, Slovenia
| | - Aharon Oren
- Department of Plant and Environmental Sciences, The Institute of Life Sciences, The Edmond J. Safra Campus, The Hebrew University of Jerusalem Givat Ram, Israel
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Vieira HGS, Grynberg P, Bitar M, Pires SDF, Hilário HO, Macedo AM, Machado CR, de Andrade HM, Franco GR. Proteomic analysis of Trypanosoma cruzi response to ionizing radiation stress. PLoS One 2014; 9:e97526. [PMID: 24842666 PMCID: PMC4026238 DOI: 10.1371/journal.pone.0097526] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 04/22/2014] [Indexed: 11/18/2022] Open
Abstract
Trypanosoma cruzi, the causative agent of Chagas disease, is extremely resistant to ionizing radiation, enduring up to 1.5 kGy of gamma rays. Ionizing radiation can damage the DNA molecule both directly, resulting in double-strand breaks, and indirectly, as a consequence of reactive oxygen species production. After a dose of 500 Gy of gamma rays, the parasite genome is fragmented, but the chromosomal bands are restored within 48 hours. Under such conditions, cell growth arrests for up to 120 hours and the parasites resume normal growth after this period. To better understand the parasite response to ionizing radiation, we analyzed the proteome of irradiated (4, 24, and 96 hours after irradiation) and non-irradiated T. cruzi using two-dimensional differential gel electrophoresis followed by mass spectrometry for protein identification. A total of 543 spots were found to be differentially expressed, from which 215 were identified. These identified protein spots represent different isoforms of only 53 proteins. We observed a tendency for overexpression of proteins with molecular weights below predicted, indicating that these may be processed, yielding shorter polypeptides. The presence of shorter protein isoforms after irradiation suggests the occurrence of post-translational modifications and/or processing in response to gamma radiation stress. Our results also indicate that active translation is essential for the recovery of parasites from ionizing radiation damage. This study therefore reveals the peculiar response of T. cruzi to ionizing radiation, raising questions about how this organism can change its protein expression to survive such a harmful stress.
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Affiliation(s)
| | - Priscila Grynberg
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, Distrito Federal, Brazil
| | - Mainá Bitar
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Simone da Fonseca Pires
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Heron Oliveira Hilário
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Andrea Mara Macedo
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Carlos Renato Machado
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Hélida Monteiro de Andrade
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Glória Regina Franco
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
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Culotta VC, Daly MJ. Manganese complexes: diverse metabolic routes to oxidative stress resistance in prokaryotes and yeast. Antioxid Redox Signal 2013; 19:933-44. [PMID: 23249283 PMCID: PMC3763226 DOI: 10.1089/ars.2012.5093] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
SIGNIFICANCE Antioxidant enzymes are thought to provide critical protection to cells against reactive oxygen species (ROS). However, many organisms can fully compensate for the loss of such enzymatic defenses by accumulating metabolites and Mn²⁺, which can form catalytic Mn-antioxidants. Accumulated metabolites can direct reactivity of Mn²⁺ with superoxide and specifically shield proteins from oxidative damage. RECENT ADVANCES There is mounting evidence that Mn-Pi (orthophosphate) complexes act as potent scavengers of superoxide in all three branches of life. Moreover, it is evident that Mn²⁺ in complexes with carbonates, peptides, nucleosides, and organic acids can also form catalytic Mn-antioxidants, pointing to diverse metabolic routes to oxidative stress resistance. CRITICAL ISSUES What conditions favor utility of Mn-metabolites versus enzymatic means for removing ROS? Mn²⁺-metabolite defenses are critical for preserving the activity of repair enzymes in Deinococcus radiodurans exposed to intense radiation stress, and in Lactobacillus plantarum, which lacks antioxidant enzymes. In other microorganisms, Mn-antioxidants can serve as an auxiliary protection when enzymatic antioxidants are insufficient or fail. These findings of a critical role of Mn-antioxidants in the survival of prokaryotes under oxidative stress parallel the trends developing for the simple eukaryote Saccharomyces cerevisiae. FUTURE DIRECTIONS Phosphates, peptides and organic acids are just a snapshot of the types of anionic metabolites that promote such reactivity of Mn²⁺. Their probable roles in pathogen defense against the host immune response and in ROS-mediated signaling pathways are also areas that are worthy of serious investigation. Moreover, it is clear that these protective chemical processes can be harnessed for practical purposes.
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Affiliation(s)
- Valeria C Culotta
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA.
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Gilmore SF, Yao AI, Tietel Z, Kind T, Facciotti MT, Parikh AN. Role of squalene in the organization of monolayers derived from lipid extracts of Halobacterium salinarum. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:7922-30. [PMID: 23713788 PMCID: PMC4438081 DOI: 10.1021/la401412t] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We have studied interfacial compressibility and lateral organization in monolayer configurations of total (squalene containing) and polar (squalene-devoid) lipid extracts of Halobacterium salinarum NRC-1, an extremely halophilic archaeon. Pressure-area isotherms derived from Langmuir experiments reveal that packing characteristics and elastic compressibility are strongly influenced by the presence of squalene in the total lipid extract. In conjunction with control experiments using mixtures of DPhPC and squalene, our results establish that the presence of squalene significantly extends elastic area compressibility of total lipid extracts, suggesting it has a role in facilitating tighter packing of archaeal lipid mixtures. Moreover, we find that squalene also influences spatial organization in archaeal membranes. Epifluorescence and atomic force microscopy characterization of Langmuir monolayers transferred onto solid hydrophilic substrates reveal an unusual domain morphology. Individual domains of microscopic dimensions (as well as their extended networks) exhibiting a peculiar bowl-like topography are evident in atomic force microscopy images. The tall rims outlining individual domains indicate that squalene accumulates at the domain periphery in a manner similar to the accumulation of cholesterol at domain boundaries in their mixtures with phospholipids. Taken together, the results presented here support the notion that squalene plays a role in modulating molecular packing and lateral organization (i.e., domain formation) in the membranes of archaea analogous to that of cholesterol in eukaryotic membranes.
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Affiliation(s)
- Sean F. Gilmore
- Department of Applied Science, University of California, Davis
| | - Andrew I. Yao
- Department of Biomedical Engineering, University of California,
Davis
- Genome Center, University of California, Davis
| | | | - Tobias Kind
- Genome Center, University of California, Davis
| | - Marc T. Facciotti
- Department of Biomedical Engineering, University of California,
Davis
- Genome Center, University of California, Davis
| | - Atul N. Parikh
- Department of Biomedical Engineering, University of California,
Davis
- Department of Chemical Engineering and Materials Science, University
of California, Davis
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Responses of Mn2+ speciation in Deinococcus radiodurans and Escherichia coli to γ-radiation by advanced paramagnetic resonance methods. Proc Natl Acad Sci U S A 2013; 110:5945-50. [PMID: 23536297 DOI: 10.1073/pnas.1303376110] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The remarkable ability of bacterium Deinococcus radiodurans to survive extreme doses of γ-rays (12,000 Gy), 20 times greater than Escherichia coli, is undiminished by loss of Mn-dependent superoxide dismutase (SodA). D. radiodurans radiation resistance is attributed to the accumulation of low-molecular-weight (LMW) "antioxidant" Mn(2+)-metabolite complexes that protect essential enzymes from oxidative damage. However, in vivo information about such complexes within D. radiodurans cells is lacking, and the idea that they can supplant reactive-oxygen-species (ROS)-scavenging enzymes remains controversial. In this report, measurements by advanced paramagnetic resonance techniques [electron-spin-echo (ESE)-EPR/electron nuclear double resonance/ESE envelope modulation (ESEEM)] reveal differential details of the in vivo Mn(2+) speciation in D. radiodurans and E. coli cells and their responses to 10 kGy γ-irradiation. The Mn(2+) of D. radiodurans exists predominantly as LMW complexes with nitrogenous metabolites and orthophosphate, with negligible EPR signal from Mn(2+) of SodA. Thus, the extreme radiation resistance of D. radiodurans cells cannot be attributed to SodA. Correspondingly, 10 kGy irradiation causes no change in D. radiodurans Mn(2+) speciation, despite the paucity of holo-SodA. In contrast, the EPR signal of E. coli is dominated by signals from low-symmetry enzyme sites such as that of SodA, with a minority pool of LMW Mn(2+) complexes that show negligible coordination by nitrogenous metabolites. Nonetheless, irradiation of E. coli majorly changes LMW Mn(2+) speciation, with extensive binding of nitrogenous ligands created by irradiation. We infer that E. coli is highly susceptible to radiation-induced ROS because it lacks an adequate supply of LMW Mn antioxidants.
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36
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Effects of intracellular Mn on the radiation resistance of the halophilic archaeon Halobacterium salinarum. Extremophiles 2013; 17:485-97. [DOI: 10.1007/s00792-013-0533-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2012] [Accepted: 03/07/2013] [Indexed: 02/01/2023]
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37
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Tabares LC, Un S. In situ determination of manganese(II) speciation in Deinococcus radiodurans by high magnetic field EPR: detection of high levels of Mn(II) bound to proteins. J Biol Chem 2013; 288:5050-5. [PMID: 23303180 DOI: 10.1074/jbc.c112.444992] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
High magnetic field high frequency electron paramagnetic resonance techniques were used to measure in situ Mn(II) speciation in Deinococcus radiodurans, a radiation-resistant bacteria capable of accumulating high concentrations of Mn(II). It was possible to identify and quantify the evolution of Mn(II) species in intact cells at various stages of growth. Aside from water, 95-GHz high field electron nuclear double resonance showed that the Mn(II) ions are bound to histidines and phosphate groups, mostly from fructose-1,6-bisphosphate but also inorganic phosphates and nucleotides. During stationary growth phase, 285-GHz continuous wave EPR measurements showed that histidine is the most common ligand to Mn(II) and that significant amounts of cellular Mn(II) in D. radiodurans are bound to peptides and proteins. As much as 40% of the total Mn(II) was in manganese superoxide dismutase, and it is this protein and not smaller manganese complexes, as has been suggested recently, that is probably the primary defense against superoxide.
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Affiliation(s)
- Leandro C Tabares
- Service de Bioénergétique, Biologie Structurale et Mécanismes, CNRS/UMR-8221, Institut de Biologie et de Technologies de Saclay, Commissariat à l'Energie Atomique-Saclay, 91191 Gif-sur-Yvette, France.
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38
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Radiation Resistance in Extremophiles: Fending Off Multiple Attacks. CELLULAR ORIGIN, LIFE IN EXTREME HABITATS AND ASTROBIOLOGY 2013. [DOI: 10.1007/978-94-007-6488-0_10] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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39
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Gabani P, Singh OV. Radiation-resistant extremophiles and their potential in biotechnology and therapeutics. Appl Microbiol Biotechnol 2012; 97:993-1004. [PMID: 23271672 DOI: 10.1007/s00253-012-4642-7] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2012] [Revised: 12/03/2012] [Accepted: 12/05/2012] [Indexed: 10/27/2022]
Abstract
Extremophiles are organisms able to thrive in extreme environmental conditions. Microorganisms with the ability to survive high doses of radiation are known as radioresistant or radiation-resistant extremophiles. Excessive or intense exposure to radiation (i.e., gamma rays, X-rays, and particularly UV radiation) can induce a variety of mutagenic and cytotoxic DNA lesions, which can lead to different forms of cancer. However, some populations of microorganisms thrive under different types of radiation due to defensive mechanisms provided by primary and secondary metabolic products, i.e., extremolytes and extremozymes. Extremolytes (including scytonemin, mycosporine-like amino acids, shinorine, porphyra-334, palythine, biopterin, and phlorotannin, among others) are able to absorb a wide spectrum of radiation while protecting the organism's DNA from being damaged. The possible commercial applications of extremolytes include anticancer drugs, antioxidants, cell-cycle-blocking agents, and sunscreens, among others. This article aims to review the strategies by which microorganisms thrive in extreme radiation environments and discuss their potential uses in biotechnology and the therapeutic industry. The major challenges that lie ahead are also discussed.
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Affiliation(s)
- Prashant Gabani
- Division of Biological and Health Sciences, University of Pittsburgh, 300 Campus Drive, Bradford, PA 16701, USA
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40
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Role of Mn2+ and compatible solutes in the radiation resistance of thermophilic bacteria and archaea. ARCHAEA-AN INTERNATIONAL MICROBIOLOGICAL JOURNAL 2012; 2012:845756. [PMID: 23209374 PMCID: PMC3505630 DOI: 10.1155/2012/845756] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 09/18/2012] [Accepted: 10/13/2012] [Indexed: 01/28/2023]
Abstract
Radiation-resistant bacteria have garnered a great deal of attention from scientists seeking to expose the mechanisms underlying their incredible survival abilities. Recent analyses showed that the resistance to ionizing radiation (IR) in the archaeon Halobacterium salinarum is dependent upon Mn-antioxidant complexes responsible for the scavenging of reactive oxygen species (ROS) generated by radiation. Here we examined the role of the compatible solutes trehalose, mannosylglycerate, and di-myo-inositol phosphate in the radiation resistance of aerobic and anaerobic thermophiles. We found that the IR resistance of the thermophilic bacteria Rubrobacter xylanophilus and Rubrobacter radiotolerans was highly correlated to the accumulation of high intracellular concentration of trehalose in association with Mn, supporting the model of Mn2+-dependent ROS scavenging in the aerobes. In contrast, the hyperthermophilic archaea Thermococcus gammatolerans and Pyrococcus furiosus did not contain significant amounts of intracellular Mn, and we found no significant antioxidant activity from mannosylglycerate and di-myo-inositol phosphate in vitro. We therefore propose that the low levels of IR-generated ROS under anaerobic conditions combined with highly constitutively expressed detoxification systems in these anaerobes are key to their radiation resistance and circumvent the need for the accumulation of Mn-antioxidant complexes in the cell.
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Sharma K, Gillum N, Boyd JL, Schmid A. The RosR transcription factor is required for gene expression dynamics in response to extreme oxidative stress in a hypersaline-adapted archaeon. BMC Genomics 2012; 13:351. [PMID: 22846541 PMCID: PMC3443676 DOI: 10.1186/1471-2164-13-351] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Accepted: 07/05/2012] [Indexed: 11/10/2022] Open
Abstract
Background Previous work has shown that the hypersaline-adapted archaeon, Halobacterium salinarum NRC-1, is highly resistant to oxidative stress caused by exposure to hydrogen peroxide, UV, and gamma radiation. Dynamic alteration of the gene regulatory network (GRN) has been implicated in such resistance. However, the molecular functions of transcription regulatory proteins involved in this response remain unknown. Results Here we have reanalyzed several existing GRN and systems biology datasets for H. salinarum to identify and characterize a novel winged helix-turn-helix transcription factor, VNG0258H, as a regulator required for reactive oxygen species resistance in this organism. This protein appears to be unique to the haloarchaea at the primary sequence level. High throughput quantitative growth assays in a deletion mutant strain implicate VNG0258H in extreme oxidative stress resistance. According to time course gene expression analyses, this transcription factor is required for the appropriate dynamic response of nearly 300 genes to reactive oxygen species damage from paraquat and hydrogen peroxide. These genes are predicted to function in repair of oxidative damage to proteins and DNA. In vivo DNA binding assays demonstrate that VNG0258H binds DNA to mediate gene regulation. Conclusions Together these results suggest that VNG0258H is a novel archaeal transcription factor that regulates gene expression to enable adaptation to the extremely oxidative, hypersaline niche of H. salinarum. We have therefore renamed VNG0258H as RosR, for reactive oxygen species regulator.
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Affiliation(s)
- Kriti Sharma
- Center for Systems Biology, Institute for Genome Sciences and Policy, Durham, NC 27710, USA
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Aguirre JD, Culotta VC. Battles with iron: manganese in oxidative stress protection. J Biol Chem 2012; 287:13541-8. [PMID: 22247543 DOI: 10.1074/jbc.r111.312181] [Citation(s) in RCA: 204] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The redox-active metal manganese plays a key role in cellular adaptation to oxidative stress. As a cofactor for manganese superoxide dismutase or through formation of non-proteinaceous manganese antioxidants, this metal can combat oxidative damage without deleterious side effects of Fenton chemistry. In either case, the antioxidant properties of manganese are vulnerable to iron. Cellular pools of iron can outcompete manganese for binding to manganese superoxide dismutase, and through Fenton chemistry, iron may counteract the benefits of non-proteinaceous manganese antioxidants. In this minireview, we highlight ways in which cells maximize the efficacy of manganese as an antioxidant in the midst of pro-oxidant iron.
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Affiliation(s)
- J Dafhne Aguirre
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland 21205, USA
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Death by protein damage in irradiated cells. DNA Repair (Amst) 2012; 11:12-21. [DOI: 10.1016/j.dnarep.2011.10.024] [Citation(s) in RCA: 180] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Accepted: 10/19/2011] [Indexed: 12/12/2022]
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Trigui H, Masmoudi S, Brochier-Armanet C, Maalej S, Dukan S. Survival of extremely and moderately halophilic isolates of Tunisian solar salterns after UV-B or oxidative stress. Can J Microbiol 2011; 57:923-33. [PMID: 22017705 DOI: 10.1139/w11-087] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Adaptation to a solar saltern environment requires mechanisms providing tolerance not only to salinity but also to UV radiation (UVR) and to reactive oxygen species (ROS). We cultivated prokaryote halophiles from two different salinity ponds: the concentrator M1 pond (240 g·L(-1) NaCl) and the crystallizer TS pond (380 g·L(-1) NaCl). We then estimated UV-B and hydrogen peroxide resistance according to the optimal salt concentration for growth of the isolates. We observed a higher biodiversity of bacterial isolates in M1 than in TS. All strains isolated from TS appeared to be extremely halophilic Archaea from the genus Halorubrum. Culturable strains isolated from M1 included extremely halophilic Archaea (genera Haloferax, Halobacterium, Haloterrigena, and Halorubrum) and moderately halophilic Bacteria (genera Halovibrio and Salicola). We also found that archaeal strains were more resistant than bacterial strains to exposure to ROS and UV-B. All organisms tested were more resistant to UV-B exposure at the optimum NaCl concentration for their growth, which is not always the case for H(2)O(2). Finally, if these results are extended to other prokaryotes present in a solar saltern, we could speculate that UVR has greater impact than ROS on the control of prokaryote biodiversity in a solar saltern.
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Affiliation(s)
- Hana Trigui
- Aix-Marseille Université, Laboratoire de chimie bactérienne, Institut de microbiologie de la Méditerranée, Centre national de la recherche scientifique, France
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