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Mathew LG, Haja DK, Pritchett C, McCormick W, Zeineddine R, Fontenot LS, Rivera ME, Glushka J, Adams MWW, Lanzilotta WN. An unprecedented function for a tungsten-containing oxidoreductase. J Biol Inorg Chem 2022; 27:747-758. [PMID: 36269456 DOI: 10.1007/s00775-022-01965-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 09/30/2022] [Indexed: 01/05/2023]
Abstract
Five tungstopterin-containing oxidoreductases were characterized from the hyperthermophile Pyrococcus furiosus. Each enzyme catalyzes the reversible conversion of one or more aldehydes to the corresponding carboxylic acid, but they have different specificities. The physiological functions of only two of these enzymes are known: one, termed GAPOR, is a glycolytic enzyme that oxidizes glyceraldehyde-3-phosphate, while the other, termed AOR, oxidizes multiple aldehydes generated during peptide fermentation. Two of the enzymes have known structures (AOR and FOR). Herein, we focus on WOR5, the fifth tungstopterin enzyme to be discovered in P. furiosus. Expression of WOR5 was previously shown to be increased during cold shock (growth at 72 ℃), although the physiological substrate is not known. To gain insight into WOR5 function, we sought to determine both its structure and identify its intracellular substrate. Crystallization experiments were performed with a concentrated cytoplasmic extract of P. furiosus grown at 72 ℃ and the structure of WOR5 was deduced from the crystals that were obtained. In contrast to a previous report, WOR5 is heterodimeric containing an additional polyferredoxin-like subunit with four [4Fe-4S] clusters. The active site structure of WOR5 is substantially different from that of AOR and FOR and the significant electron density observed adjacent to the tungsten cofactor of WOR5 was modeled as an aliphatic sulfonate. Biochemical assays and product analysis confirmed that WOR5 is an aliphatic sulfonate ferredoxin oxidoreductase (ASOR). A catalytic mechanism for ASOR is proposed based on the structural information and the potential role of ASOR in the cold-shock response is discussed.
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Affiliation(s)
- Liju G Mathew
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Dominik K Haja
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Clayton Pritchett
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Winston McCormick
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Robbie Zeineddine
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Leo S Fontenot
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Mario E Rivera
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - John Glushka
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA.
| | - William N Lanzilotta
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA.
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Suyal DC, Joshi D, Kumar S, Bhatt P, Narayan A, Giri K, Singh M, Soni R, Kumar R, Yadav A, Devi R, Kaur T, Kour D, Yadav AN. Himalayan Microbiomes for Agro-environmental Sustainability: Current Perspectives and Future Challenges. MICROBIAL ECOLOGY 2022; 84:643-675. [PMID: 34647148 DOI: 10.1007/s00248-021-01849-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 08/23/2021] [Indexed: 06/13/2023]
Abstract
The Himalayas are one of the most mystical, yet least studied terrains of the world. One of Earth's greatest multifaceted and diverse montane ecosystems is also one of the thirty-four global biodiversity hotspots of the world. These are supposed to have been uplifted about 60-70 million years ago and support, distinct environments, physiography, a variety of orogeny, and great biological diversity (plants, animals, and microbes). Microbes are the pioneer colonizer of the Himalayas that are involved in various bio-geological cycles and play various significant roles. The applications of Himalayan microbiomes inhabiting in lesser to greater Himalayas have been recognized. The researchers explored the applications of indigenous microbiomes in both agricultural and environmental sectors. In agriculture, microbiomes from Himalayan regions have been suggested as better biofertilizers and biopesticides for the crops growing at low temperature and mountainous areas as they help in the alleviation of cold stress and other biotic stresses. Along with alleviation of low temperature, Himalayan microbes also have the capability to enhance plant growth by availing the soluble form of nutrients like nitrogen, phosphorus, potassium, zinc, and iron. These microbes have been recognized for producing plant growth regulators (abscisic acid, auxin, cytokinin, ethylene, and gibberellins). These microbes have been reported for bioremediating the diverse pollutants (pesticides, heavy metals, and xenobiotics) for environmental sustainability. In the current perspectives, present review provides a detailed discussion on the ecology, biodiversity, and adaptive features of the native Himalayan microbiomes in view to achieve agro-environmental sustainability.
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Affiliation(s)
- Deep Chandra Suyal
- Department of Microbiology, Akal College of Basic Sciences, Eternal University, Sirmaur, Himachal Pradesh, India
| | - Divya Joshi
- Uttarakhand Pollution Control Board, Regional Office, Kashipur, Uttarakhand, India
| | - Saurabh Kumar
- Division of Crop Research, Research Complex for Eastern Region, Patna, Bihar, India
| | - Pankaj Bhatt
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Laboratory for Lingnan Modern Agriculture, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, 510642, China
| | - Arun Narayan
- Forest Research Institute, Dehradun, 2480 06, India
| | - Krishna Giri
- Rain Forest Research Institute, Jorhat, 785 010, India
| | - Manali Singh
- Department of Biotechnology, Invertis Institute of Engineering and Technology (IIET), Invertis University, Bareilly, 243123, Uttar Pradesh, India
| | - Ravindra Soni
- Department of Agricultural Microbiology, College of Agriculture, Indira Gandhi Krishi Vishwa Vidyalaya, Raipur, Chhattisgarh, India
| | - Rakshak Kumar
- Department of Biotechnology, CSIR-Institute of Himalayan Bioresource Technology, Palampur, India
| | - Ashok Yadav
- Department of Botany, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Rubee Devi
- Microbial Biotechnology Laboratory, Department of Biotechnology, Dr. Khem Singh Gill Akal College of Agriculture, Eternal University, Baru Sahib, Sirmour, Himachal Pradesh, India
| | - Tanvir Kaur
- Microbial Biotechnology Laboratory, Department of Biotechnology, Dr. Khem Singh Gill Akal College of Agriculture, Eternal University, Baru Sahib, Sirmour, Himachal Pradesh, India
| | - Divjot Kour
- Microbial Biotechnology Laboratory, Department of Biotechnology, Dr. Khem Singh Gill Akal College of Agriculture, Eternal University, Baru Sahib, Sirmour, Himachal Pradesh, India
| | - Ajar Nath Yadav
- Microbial Biotechnology Laboratory, Department of Biotechnology, Dr. Khem Singh Gill Akal College of Agriculture, Eternal University, Baru Sahib, Sirmour, Himachal Pradesh, India.
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3
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Somero GN. Solutions: how adaptive changes in cellular fluids enable marine life to cope with abiotic stressors. MARINE LIFE SCIENCE & TECHNOLOGY 2022; 4:389-413. [PMID: 37073170 PMCID: PMC10077225 DOI: 10.1007/s42995-022-00140-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 06/15/2022] [Indexed: 05/03/2023]
Abstract
The seas confront organisms with a suite of abiotic stressors that pose challenges for physiological activity. Variations in temperature, hydrostatic pressure, and salinity have potential to disrupt structures, and functions of all molecular systems on which life depends. During evolution, sequences of nucleic acids and proteins are adaptively modified to "fit" these macromolecules for function under the particular abiotic conditions of the habitat. Complementing these macromolecular adaptations are alterations in compositions of solutions that bathe macromolecules and affect stabilities of their higher order structures. A primary result of these "micromolecular" adaptations is preservation of optimal balances between conformational rigidity and flexibility of macromolecules. Micromolecular adaptations involve several families of organic osmolytes, with varying effects on macromolecular stability. A given type of osmolyte generally has similar effects on DNA, RNA, proteins and membranes; thus, adaptive regulation of cellular osmolyte pools has a global effect on macromolecules. These effects are mediated largely through influences of osmolytes and macromolecules on water structure and activity. Acclimatory micromolecular responses are often critical in enabling organisms to cope with environmental changes during their lifetimes, for example, during vertical migration in the water column. A species' breadth of environmental tolerance may depend on how effectively it can vary the osmolyte composition of its cellular fluids in the face of stress. Micromolecular adaptations remain an under-appreciated aspect of evolution and acclimatization. Further study can lead to a better understanding of determinants of environmental tolerance ranges and to biotechnological advances in designing improved stabilizers for biological materials.
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Affiliation(s)
- George N. Somero
- Department of Biology, Hopkins Marine Station, Stanford University, Pacific Grove, CA 93950 USA
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4
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Schwentner A, Neugebauer H, Weinmann S, Santos H, Eikmanns BJ. Exploring the Potential of Corynebacterium glutamicum to Produce the Compatible Solute Mannosylglycerate. Front Bioeng Biotechnol 2021; 9:748155. [PMID: 34621731 PMCID: PMC8490865 DOI: 10.3389/fbioe.2021.748155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 08/26/2021] [Indexed: 11/13/2022] Open
Abstract
The compatible solute mannosylglycerate (MG) has exceptional properties in terms of protein stabilization and protection under salt, heat, and freeze-drying stresses as well as against protein aggregation. Due to these characteristics, MG possesses large potential for clinical and biotechnological applications. To achieve efficient MG production, Corynebacterium glutamicum was equipped with a bifunctional MG synthase (encoded by mgsD and catalyzing the condensation of 3-phosphoglycerate and GDP-mannose to MG) from Dehalococcoides mccartyi. The resulting strain C. glutamicum (pEKEx3 mgsD) intracellularly accumulated about 111 mM MG (60 ± 9 mg gCDW -1) with 2% glucose as a carbon source. To enable efficient mannose metabolization, the native manA gene, encoding mannose 6-phosphate isomerase, was overexpressed. Combined overexpression of manA and mgsD from two plasmids in C. glutamicum resulted in intracellular MG accumulation of up to ca. 329 mM [corresponding to 177 mg g cell dry weight (CDW) -1] with glucose, 314 mM (168 mg gCDW -1) with glucose plus mannose, and 328 mM (176 mg gCDW -1) with mannose as carbon source(s), respectively. The product was successfully extracted from cells by using a cold water shock, resulting in up to 5.5 mM MG (1.48 g L-1) in supernatants. The two-plasmid system was improved by integrating the mgsD gene into the manA-bearing plasmid and the resulting strain showed comparable production but faster growth. Repeated cycles of growth/production and extraction of MG in a bacterial milking-like experiment showed that cells could be recycled, which led to a cumulative MG production of 19.9 mM (5.34 g L-1). The results show that the newly constructed C. glutamicum strain produces MG from glucose and mannose and that a cold water shock enables extraction of MG from the cytosol into the medium.
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Affiliation(s)
- Andreas Schwentner
- Institute of Microbiology and Biotechnology, Ulm University, Ulm, Germany
| | - Heiko Neugebauer
- Institute of Microbiology and Biotechnology, Ulm University, Ulm, Germany
| | - Serin Weinmann
- Institute of Microbiology and Biotechnology, Ulm University, Ulm, Germany
| | - Helena Santos
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
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Kourilova X, Novackova I, Koller M, Obruca S. Evaluation of mesophilic Burkholderia sacchari, thermophilic Schlegelella thermodepolymerans and halophilic Halomonas halophila for polyhydroxyalkanoates production on model media mimicking lignocellulose hydrolysates. BIORESOURCE TECHNOLOGY 2021; 325:124704. [PMID: 33493750 DOI: 10.1016/j.biortech.2021.124704] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 01/07/2021] [Accepted: 01/08/2021] [Indexed: 06/12/2023]
Abstract
In this work, the mesophilic bacterium Burkholderia sacchari, the halophilic bacterium Halomonas halophila, and the thermophilic bacterium Schlegelella thermodepolymerans were evaluated with regards to their suitability for polyhydroxyalkanoates (PHA) production from model media mimicking lignocellulose hydrolysates. B. sacchari was capable of utilizing all the tested "model hydrolysates", yielding comparable PHA titers and turning out as very robust against lignocellulose-derived microbial inhibitors. On the contrary, H. halophila reached substantially higher PHA titers on hexoses-rich media, while S. thermodepolymerans preferred media rich in pentoses. Both extremophiles were more sensitive to microbial inhibitors than B. sacchari. Nevertheless, considering substantially higher PHA productivity of both extremophiles even in the presence of microbial inhibitors and also other positive factors associated with utilization of extremophiles, such as the reduced risk of microbial contamination, both H. halophila and S. thermodepolymerans are auspicious candidates for sustainable PHA production from abundantly available, inexpensive lignocelluloses.
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Affiliation(s)
- Xenie Kourilova
- Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech Republic
| | - Ivana Novackova
- Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech Republic
| | - Martin Koller
- Institute of Chemistry, NAWI Graz, University of Graz, Heinrichstrasse 28/VI, 8010 Graz, Austria; ARENA Arbeitsgemeinschaft für Ressourcenschonende & Nachhaltige Technologien, Inffeldgasse 21b, 11 8010 Graz, Austria
| | - Stanislav Obruca
- Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech Republic.
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6
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Becker J, Wittmann C. Microbial production of extremolytes — high-value active ingredients for nutrition, health care, and well-being. Curr Opin Biotechnol 2020; 65:118-128. [DOI: 10.1016/j.copbio.2020.02.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 02/14/2020] [Accepted: 02/17/2020] [Indexed: 01/09/2023]
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7
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Zhao W, Ma X, Liu X, Jian H, Zhang Y, Xiao X. Cross-Stress Adaptation in a Piezophilic and Hyperthermophilic Archaeon From Deep Sea Hydrothermal Vent. Front Microbiol 2020; 11:2081. [PMID: 33013758 PMCID: PMC7511516 DOI: 10.3389/fmicb.2020.02081] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 08/07/2020] [Indexed: 11/13/2022] Open
Abstract
Hyperthermophiles, living in environments above 80°C and usually coupling with multi-extreme environmental stresses, have drawn great attention due to their application potential in biotechnology and being the primitive extant forms of life. Studies on their survival and adaptation mechanisms have extended our understanding on how lives thrive under extreme conditions. During these studies, the "cross-stress" behavior in various organisms has been observed between the extreme high temperature and other environmental stresses. Despite the broad observation, the global view of the cross-stress behavior remains unclear in hyperthermophiles, leaving a knowledge gap in our understanding of extreme adaptation. In this study, we performed a global quantitative proteomic analysis under extreme temperatures, pH, hydrostatic pressure (HP), and salinity on an archaeal strain, Thermococcus eurythermalis A501, which has outstanding growth capability on a wide range of temperatures (50-100°C), pH (4-9), and HPs (0.1-70 MPa), but a narrow range of NaCl (1.0-5.0 %, w/v). The proteomic analysis (79.8% genome coverage) demonstrated that approximately 61.5% of the significant differentially expressed proteins (DEPs) responded to multiple stresses. The responses to most of the tested stresses were closely correlated, except the responses to high salinity and low temperature. The top three enriched universal responding processes include the biosynthesis and protection of macromolecules, biosynthesis and metabolism of amino acids, ion transport, and binding activities. In addition, this study also revealed that the specific dual-stress responding processes, such as the membrane lipids for both cold and HP stresses and the signal transduction for both hyperosmotic and heat stresses, as well as the sodium-dependent energetic processes might be the limiting factor of the growth range in salinity. The present study is the first to examine the global cross-stress responses in a piezophilic hyperthermophile at the proteomic level. Our findings provide direct evidences of the cross-stress adaptation strategy (33.5% of coding-genes) to multiple stresses and highlight the specific and unique responding processes (0.22-0.63% of coding genes for each) to extreme temperature, pH, salinity, and pressure, which are highly relevant to the fields of evolutionary biology as well as next generation industrial biotechnology (NGIB).
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Affiliation(s)
- Weishu Zhao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaopan Ma
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaoxia Liu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Huahua Jian
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Yu Zhang
- State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai, China
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xiang Xiao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
- State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai, China
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
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8
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Nasr MA, Dovbeshko GI, Bearne SL, El‐Badri N, Matta CF. Heat Shock Proteins in the “Hot” Mitochondrion: Identity and Putative Roles. Bioessays 2019; 41:e1900055. [DOI: 10.1002/bies.201900055] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 07/08/2019] [Indexed: 11/10/2022]
Affiliation(s)
- Mohamed A. Nasr
- Department of Chemistry and PhysicsMount Saint Vincent University Halifax Nova Scotia B3M 2J6 Canada
- Center of Excellence for Stem Cells and Regenerative Medicine (CESC)Zewail City of Science and Technology 6th of October City 12588 Egypt
| | - Galina I. Dovbeshko
- Department of Physics of Biological SystemsInstitute of Physics of the National Academy of Sciences of Ukraine Prospekt Nauki 46 Kiev 03039 Ukraine
| | - Stephen L. Bearne
- Department of ChemistryDalhousie University Halifax Nova Scotia B3H 4R2 Canada
- Department of Biochemistry and Molecular BiologyDalhousie University Halifax Nova Scotia B3H 4R2 Canada
| | - Nagwa El‐Badri
- Center of Excellence for Stem Cells and Regenerative Medicine (CESC)Zewail City of Science and Technology 6th of October City 12588 Egypt
| | - Chérif F. Matta
- Department of Chemistry and PhysicsMount Saint Vincent University Halifax Nova Scotia B3M 2J6 Canada
- Department of ChemistryDalhousie University Halifax Nova Scotia B3H 4R2 Canada
- Department of ChemistrySaint Mary's University Halifax Nova Scotia B3H 3C3 Canada
- Département de chimieUniversité Laval Québec Québec G1V 0A6 Canada
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9
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Houghton KM, Carere CR, Stott MB, McDonald IR. Thermophilic methanotrophs: in hot pursuit. FEMS Microbiol Ecol 2019; 95:5543213. [DOI: 10.1093/femsec/fiz125] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 07/31/2019] [Indexed: 11/13/2022] Open
Abstract
ABSTRACTMethane is a potent greenhouse gas responsible for 20–30% of global climate change effects. The global methane budget is ∼500–600 Tg y−1, with the majority of methane produced via microbial processes, including anthropogenic-mediated sources such as ruminant animals, rice fields, sewage treatment facilities and landfills. It is estimated that microbially mediated methane oxidation (methanotrophy) consumes >50% of global methane flux each year. Methanotrophy research has primarily focused on mesophilic methanotrophic representatives and cooler environments such as freshwater, wetlands or marine habitats from which they are sourced. Nevertheless, geothermal emissions of geological methane, produced from magma and lithosphere degassing micro-seepages, mud volcanoes and other geological sources, contribute an estimated 33–75 Tg y−1 to the global methane budget. The aim of this review is to summarise current literature pertaining to the activity of thermophilic and thermotolerant methanotrophs, both proteobacterial (Methylocaldum, Methylococcus, Methylothermus) and verrucomicrobial (Methylacidiphilum). We assert, on the basis of recently reported molecular and geochemical data, that geothermal ecosystems host hitherto unidentified species capable of methane oxidation at higher temperatures.
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Affiliation(s)
- Karen M Houghton
- GNS Science, Wairakei Research Centre, 114 Karetoto Rd, Taupō 3384, New Zealand
- School of Science, University of Waikato, Knighton Rd, Hamilton 3240, New Zealand
| | - Carlo R Carere
- GNS Science, Wairakei Research Centre, 114 Karetoto Rd, Taupō 3384, New Zealand
- Department of Chemical and Process Engineering, University of Canterbury, 20 Kirkwood Ave, Upper Riccarton, Christchurch 8041, New Zealand
| | - Matthew B Stott
- GNS Science, Wairakei Research Centre, 114 Karetoto Rd, Taupō 3384, New Zealand
- School of Biological Sciences, University of Canterbury, 20 Kirkwood Ave, Upper Riccarton, Christchurch 8041, New Zealand
| | - Ian R McDonald
- School of Science, University of Waikato, Knighton Rd, Hamilton 3240, New Zealand
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Esteves AM, Graça G, Peyriga L, Torcato IM, Borges N, Portais JC, Santos H. Combined transcriptomics-metabolomics profiling of the heat shock response in the hyperthermophilic archaeon Pyrococcus furiosus. Extremophiles 2018; 23:101-118. [PMID: 30430272 DOI: 10.1007/s00792-018-1065-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 10/28/2018] [Indexed: 12/25/2022]
Abstract
Pyrococcus furiosus is a remarkable archaeon able to grow at temperatures around 100 °C. To gain insight into how this model hyperthermophile copes with heat stress, we compared transcriptomic and metabolomic data of cells subjected to a temperature shift from 90 °C to 97 °C. In this study, we used RNA-sequencing to characterize the global variation in gene expression levels, while nuclear magnetic resonance (NMR) and targeted ion exchange liquid chromatography-mass spectrometry (LC-MS) were used to determine changes in metabolite levels. Of the 552 differentially expressed genes in response to heat shock conditions, 257 were upregulated and 295 were downregulated. In particular, there was a significant downregulation of genes for synthesis and transport of amino acids. At the metabolite level, 37 compounds were quantified. The level of di-myo-inositol phosphate, a canonical heat stress solute among marine hyperthermophiles, increased considerably (5.4-fold) at elevated temperature. Also, the levels of mannosylglycerate, UDP-N-acetylglucosamine (UDPGlcNac) and UDP-N-acetylgalactosamine were enhanced. The increase in the pool of UDPGlcNac was concurrent with an increase in the transcript levels of the respective biosynthetic genes. This work provides the first metabolomic analysis of the heat shock response of a hyperthermophile.
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Affiliation(s)
- Ana M Esteves
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-127, Oeiras, Portugal
| | - Gonçalo Graça
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-127, Oeiras, Portugal
| | - Lindsay Peyriga
- LISBP, Université de Toulouse, CNRS, INRA, INSA, 31077, Toulouse, France.,MetaToul-MetaboHUB, National Infrastructure of Metabolomics and Fluxomics, 31077, Toulouse, France
| | - Inês M Torcato
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-127, Oeiras, Portugal
| | - Nuno Borges
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-127, Oeiras, Portugal
| | - Jean-Charles Portais
- LISBP, Université de Toulouse, CNRS, INRA, INSA, 31077, Toulouse, France.,MetaToul-MetaboHUB, National Infrastructure of Metabolomics and Fluxomics, 31077, Toulouse, France.,Université Paul Sabatier, Université de Toulouse, 31062, Toulouse, France
| | - Helena Santos
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-127, Oeiras, Portugal.
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11
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Zeidler S, Hubloher J, Schabacker K, Lamosa P, Santos H, Müller V. Trehalose, a temperature- and salt-induced solute with implications in pathobiology of Acinetobacter baumannii. Environ Microbiol 2017; 19:5088-5099. [PMID: 29124876 DOI: 10.1111/1462-2920.13987] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 11/03/2017] [Indexed: 01/01/2023]
Abstract
Acinetobacter baumannii is an opportunistic human pathogen that has become a global threat to healthcare institutions worldwide. A major factor contributing to success of this bacterium is its outstanding ability to survive on dry surfaces. The molecular basis for desiccation resistance is not completely understood. This study focused on growth under osmotic stress and aimed to identify the pool of compatible solutes synthesized in response to these low water activity conditions. A. baumannii produced mannitol as compatible solute, but in contrast to Acinetobacter baylyi, also trehalose was accumulated in response to increasing NaCl concentrations. The genome of A. baumannii encodes a trehalose-6-phosphate phosphatase (OtsB) and a trehalose-6-phosphate synthase (OtsA). Deletion of otsB abolished trehalose formation, demonstrating that otsB is essential for trehalose biosynthesis. Growth of the mutant was neither impaired at low salt nor at 500 mM NaCl, but it did not grow at high temperatures, indicating a dual function of trehalose in osmo- and thermoprotection. This led us to analyse temperature dependence of trehalose formation. Indeed, expression of otsB was not only induced by high osmolarity but also by high temperature. Concurrently, trehalose was accumulated in cells grown at high temperature. Taken together, these data point to an important role of trehalose in A. baumannii beyond osmoprotection.
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Affiliation(s)
- Sabine Zeidler
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Goethe-University Frankfurt am Main, Germany
| | - Josephine Hubloher
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Goethe-University Frankfurt am Main, Germany
| | - Kim Schabacker
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Goethe-University Frankfurt am Main, Germany
| | - Pedro Lamosa
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Helena Santos
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Volker Müller
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Goethe-University Frankfurt am Main, Germany
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Chen X, Gao C, Guo L, Hu G, Luo Q, Liu J, Nielsen J, Chen J, Liu L. DCEO Biotechnology: Tools To Design, Construct, Evaluate, and Optimize the Metabolic Pathway for Biosynthesis of Chemicals. Chem Rev 2017; 118:4-72. [DOI: 10.1021/acs.chemrev.6b00804] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Xiulai Chen
- State
Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key
Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Cong Gao
- State
Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key
Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Liang Guo
- State
Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key
Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Guipeng Hu
- State
Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key
Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Qiuling Luo
- State
Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key
Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Jia Liu
- State
Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key
Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Jens Nielsen
- Department
of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg SE-412 96, Sweden
- Novo
Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK2800 Lyngby, Denmark
| | - Jian Chen
- State
Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key
Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Liming Liu
- State
Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Department
of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg SE-412 96, Sweden
- Key
Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
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13
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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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14
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Beblo-Vranesevic K, Galinski EA, Rachel R, Huber H, Rettberg P. Influence of osmotic stress on desiccation and irradiation tolerance of (hyper)-thermophilic microorganisms. Arch Microbiol 2016; 199:17-28. [PMID: 27443666 DOI: 10.1007/s00203-016-1269-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 06/27/2016] [Accepted: 07/13/2016] [Indexed: 11/25/2022]
Abstract
This study examined the influence of prior salt adaptation on the survival rate of (hyper)-thermophilic bacteria and archaea after desiccation and UV or ionizing irradiation treatment. Survival rates after desiccation of Hydrogenothermus marinus and Archaeoglobus fulgidus increased considerably when the cells were cultivated at higher salt concentrations before drying. By doubling the concentration of NaCl, a 30 times higher survival rate of H. marinus after desiccation was observed. Under salt stress, the compatible solute diglycerol phosphate in A. fulgidus and glucosylglycerate in H. marinus accumulated in the cytoplasm. Several different compatible solutes were added as protectants to A. fulgidus and H. marinus before desiccation treatment. Some of these had similar effects as intracellularly produced compatible solutes. The survival rates of H. marinus and A. fulgidus after exposure to UV-C (254 nm) or ionizing X-ray/gamma radiation were irrespective of the salt-induced synthesis or the addition of compatible solutes.
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Affiliation(s)
- Kristina Beblo-Vranesevic
- Institute of Aerospace Medicine, Radiation Biology Division, German Aerospace Center (DLR e.V.), Linder Höhe, 51147, Cologne, Germany.
| | - Erwin A Galinski
- Institute of Microbiology and Biotechnology, Rheinische Friedrich-Wilhelms University, Bonn, Germany
| | - Reinhard Rachel
- Faculty of Biology and Preclinical Medicine, Center for Electron Microscopy, University Regensburg, Regensburg, Germany
| | - Harald Huber
- Faculty of Biology and Preclinical Medicine, Institute for Microbiology and Archaea Center, University of Regensburg, Regensburg, Germany
| | - Petra Rettberg
- Institute of Aerospace Medicine, Radiation Biology Division, German Aerospace Center (DLR e.V.), Linder Höhe, 51147, Cologne, Germany
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15
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Cario A, Jebbar M, Thiel A, Kervarec N, Oger PM. Molecular chaperone accumulation as a function of stress evidences adaptation to high hydrostatic pressure in the piezophilic archaeon Thermococcus barophilus. Sci Rep 2016; 6:29483. [PMID: 27378270 PMCID: PMC4932500 DOI: 10.1038/srep29483] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 06/20/2016] [Indexed: 11/23/2022] Open
Abstract
The accumulation of mannosyl-glycerate (MG), the salinity stress response osmolyte of Thermococcales, was investigated as a function of hydrostatic pressure in Thermococcus barophilus strain MP, a hyperthermophilic, piezophilic archaeon isolated from the Snake Pit site (MAR), which grows optimally at 40 MPa. Strain MP accumulated MG primarily in response to salinity stress, but in contrast to other Thermococcales, MG was also accumulated in response to thermal stress. MG accumulation peaked for combined stresses. The accumulation of MG was drastically increased under sub-optimal hydrostatic pressure conditions, demonstrating that low pressure is perceived as a stress in this piezophile, and that the proteome of T. barophilus is low-pressure sensitive. MG accumulation was strongly reduced under supra-optimal pressure conditions clearly demonstrating the structural adaptation of this proteome to high hydrostatic pressure. The lack of MG synthesis only slightly altered the growth characteristics of two different MG synthesis deletion mutants. No shift to other osmolytes was observed. Altogether our observations suggest that the salinity stress response in T. barophilus is not essential and may be under negative selective pressure, similarly to what has been observed for its thermal stress response.
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Affiliation(s)
- Anaïs Cario
- Univ Lyon, ENS de Lyon, CNRS UMR 5276, Lyon, France
| | - Mohamed Jebbar
- Univ Brest, CNRS, Ifremer, UMR 6197-Laboratoire de Microbiologie des Environnements Extrêmes (LM2E), Institut Universitaire Européen de la Mer (IUEM), rue Dumont d'Urville, 29 280 Plouzané, France
| | - Axel Thiel
- Univ Brest, CNRS, Ifremer, UMR 6197-Laboratoire de Microbiologie des Environnements Extrêmes (LM2E), Institut Universitaire Européen de la Mer (IUEM), rue Dumont d'Urville, 29 280 Plouzané, France
| | - Nelly Kervarec
- Univ Brest, PLATE-FORME TECHNOLOGIQUE RMN-RPE-SM, UFR Sciences et Techniques, Avenue Le Gorgeu, Brest, France
| | - Phil M Oger
- Univ Lyon, ENS de Lyon, CNRS UMR 5276, Lyon, France.,Univ Lyon, INSA de Lyon, CNRS UMR 5240, Lyon, France
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16
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A novel ammonia-oxidizing archaeon from wastewater treatment plant: Its enrichment, physiological and genomic characteristics. Sci Rep 2016; 6:23747. [PMID: 27030530 PMCID: PMC4814877 DOI: 10.1038/srep23747] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Accepted: 03/14/2016] [Indexed: 12/17/2022] Open
Abstract
Ammonia-oxidizing archaea (AOA) are recently found to participate in the ammonia removal processes in wastewater treatment plants (WWTPs), similar to their bacterial counterparts. However, due to lack of cultivated AOA strains from WWTPs, their functions and contributions in these systems remain unclear. Here we report a novel AOA strain SAT1 enriched from activated sludge, with its physiological and genomic characteristics investigated. The maximal 16S rRNA gene similarity between SAT1 and other reported AOA strain is 96% (with “Ca. Nitrosotenuis chungbukensis”), and it is affiliated with Wastewater Cluster B (WWC-B) based on amoA gene phylogeny, a cluster within group I.1a and specific for activated sludge. Our strain is autotrophic, mesophilic (25 °C–33 °C) and neutrophilic (pH 5.0–7.0). Its genome size is 1.62 Mb, with a large fragment inversion (accounted for 68% genomic size) inside. The strain could not utilize urea due to truncation of the urea transporter gene. The lack of the pathways to synthesize usual compatible solutes makes it intolerant to high salinity (>0.03%), but could adapt to low salinity (0.005%) environments. This adaptation, together with possibly enhanced cell-biofilm attachment ability, makes it suitable for WWTPs environment. We propose the name “Candidatus Nitrosotenuis cloacae” for the strain SAT1.
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17
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Jiang K, Xue Y, Ma Y. Identification of N(α)-acetyl-α-lysine as a probable thermolyte and its accumulation mechanism in Salinicoccus halodurans H3B36. Sci Rep 2015; 5:18518. [PMID: 26687465 PMCID: PMC4685198 DOI: 10.1038/srep18518] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 10/30/2015] [Indexed: 11/09/2022] Open
Abstract
Salinicoccus halodurans H3B36 is a moderate halophile that was isolated from a 3.2-m-deep sediment sample in Qaidam Basin, China. Our results suggest that N(α)-acetyl-α-lysine can accumulate and act as a probable thermolyte in this strain. The accumulation mechanism and biosynthetic pathway for this rare compatible solute were also elucidated. We confirmed that the de novo synthesis pathway of N(α)-acetyl-α-lysine in this strain starts from aspartate and passes through lysine. Through RNA sequencing, we also found an 8-gene cluster (orf_1582-1589) and another gene (orf_2472) that might encode the biosynthesis of N(α)-acetyl-α-lysine in S. halodurans H3B36. Orf_192, orf_193, and orf_1259 might participate in the transportation of precursors for generating N(α)-acetyl-α-lysine under the heat stress. The transcriptome reported here also generated a global view of heat-induced changes and yielded clues for studying the regulation of N(α)-acetyl-α-lysine accumulation. Heat stress triggered a global transcriptional disturbance and generated a series of actions to adapt the strain to heat stress. Furthermore, the transcriptomic results showed that the regulon of RpoN (orf_2534) may be critical to conferring heat stress tolerance and survival to S. halodurans.
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Affiliation(s)
- Kai Jiang
- State Key Laboratory of Microbial Resources and National Engineering Laboratory for Industrial Enzymes, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yanfen Xue
- State Key Laboratory of Microbial Resources and National Engineering Laboratory for Industrial Enzymes, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Yanhe Ma
- State Key Laboratory of Microbial Resources and National Engineering Laboratory for Industrial Enzymes, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
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18
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Cario A, Mizgier A, Thiel A, Jebbar M, Oger PM. Restoration of the di-myo-inositol-phosphate pathway in the piezo-hyperthermophilic archaeon Thermococcus barophilus. Biochimie 2015; 118:286-93. [DOI: 10.1016/j.biochi.2015.05.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 05/13/2015] [Indexed: 12/16/2022]
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19
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Raddadi N, Cherif A, Daffonchio D, Neifar M, Fava F. Biotechnological applications of extremophiles, extremozymes and extremolytes. Appl Microbiol Biotechnol 2015; 99:7907-13. [PMID: 26272092 DOI: 10.1007/s00253-015-6874-9] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 07/20/2015] [Accepted: 07/22/2015] [Indexed: 11/24/2022]
Abstract
In the last decade, attention to extreme environments has increased because of interests to isolate previously unknown extremophilic microorganisms in pure culture and to profile their metabolites. Microorganisms that live in extreme environments produce extremozymes and extremolytes that have the potential to be valuable resources for the development of a bio-based economy through their application to white, red, and grey biotechnologies. Here, we provide an overview of extremophile ecology, and we review the most recent applications of microbial extremophiles and the extremozymes and extremolytes they produce to biotechnology.
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Affiliation(s)
- Noura Raddadi
- Department of Civil, Chemical, Environmental and Materials Engineering (DICAM), University of Bologna, via Terracini 28, 40131, Bologna, Italy,
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Jia B, Liu J, Van Duyet L, Sun Y, Xuan YH, Cheong GW. Proteome profiling of heat, oxidative, and salt stress responses in Thermococcus kodakarensis KOD1. Front Microbiol 2015; 6:605. [PMID: 26150806 PMCID: PMC4473059 DOI: 10.3389/fmicb.2015.00605] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 06/02/2015] [Indexed: 01/18/2023] Open
Abstract
The thermophilic species, Thermococcus kodakarensis KOD1, a model microorganism for studying hyperthermophiles, has adapted to optimal growth under conditions of high temperature and salinity. However, the environmental conditions for the strain are not always stable, and this strain might face different stresses. In the present study, we compared the proteome response of T. kodakarensis to heat, oxidative, and salt stresses using two-dimensional electrophoresis, and protein spots were identified through MALDI-TOF/MS. Fifty-nine, forty-two, and twenty-nine spots were induced under heat, oxidative, and salt stresses, respectively. Among the up-regulated proteins, four proteins (a hypothetical protein, pyridoxal biosynthesis lyase, peroxiredoxin, and protein disulphide oxidoreductase) were associated with all three stresses. Gene ontology analysis showed that these proteins were primarily involved metabolic and cellular processes. The KEGG pathway analysis suggested that the main metabolic pathways involving these enzymes were related to carbohydrate metabolism, secondary metabolite synthesis, and amino acid biosynthesis. These data might enhance our understanding of the functions and molecular mechanisms of thermophilic Archaea for survival and adaptation in extreme environments.
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Affiliation(s)
- Baolei Jia
- Department of Life Science, Chung-Ang University, Seoul South Korea ; Division of Applied Life Sciences and Research Institute of Natural Science, Gyeongsang National University Jinju, South Korea
| | - Jinliang Liu
- College of Plant Sciences, Jilin University Changchun, China
| | - Le Van Duyet
- Division of Applied Life Sciences and Research Institute of Natural Science, Gyeongsang National University Jinju, South Korea
| | - Ying Sun
- College of Plant Sciences, Jilin University Changchun, China
| | - Yuan H Xuan
- College of Plant Protection, Shenyang Agricultural University Shenyang, China
| | - Gang-Won Cheong
- Division of Applied Life Sciences and Research Institute of Natural Science, Gyeongsang National University Jinju, South Korea
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21
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Jorge CD, Borges N, Santos H. A novel pathway for the synthesis of inositol phospholipids uses cytidine diphosphate (CDP)-inositol as donor of the polar head group. Environ Microbiol 2015; 17:2492-504. [PMID: 25472423 DOI: 10.1111/1462-2920.12734] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 11/26/2014] [Accepted: 11/27/2014] [Indexed: 11/28/2022]
Abstract
We describe a novel biosynthetic pathway for glycerophosphoinositides in Rhodothermus marinus in which inositol is activated by cytidine triphosphate (CTP); this is unlike all known pathways that involve activation of the lipid group instead. This work was motivated by the detection in the R. marinus genome of a gene with high similarity to CTP:L-myo-inositol-1-phosphate cytidylyltransferase, the enzyme that synthesizes cytidine diphosphate (CDP)-inositol, a metabolite only known in the synthesis of di-myo-inositol phosphate. However, this solute is absent in R. marinus. The fate of radiolabelled CDP-inositol was investigated in cell extracts to reveal that radioactive inositol was incorporated into the chloroform-soluble fraction. Mass spectrometry showed that the major lipid product has a molecular mass of 810 Da and contains inositol phosphate and alkyl chains attached to glycerol by ether bonds. The occurrence of ether-linked lipids is rare in bacteria and has not been described previously in R. marinus. The relevant synthase was identified by functional expression of the candidate gene in Escherichia coli. The enzyme catalyses the transfer of L-myo-inositol-1-phosphate from CDP-inositol to dialkylether glycerol yielding dialkylether glycerophosphoinositol. Database searching showed homologous proteins in two bacterial classes, Sphingobacteria and Alphaproteobacteria. This is the first report of the involvement of CDP-inositol in phospholipid synthesis.
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Affiliation(s)
- Carla D Jorge
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República-EAN, Apartado 127, Oeiras, 2780-157, Portugal
| | - Nuno Borges
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República-EAN, Apartado 127, Oeiras, 2780-157, Portugal
| | - Helena Santos
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República-EAN, Apartado 127, Oeiras, 2780-157, Portugal
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