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Davoudpour Y, Kümmel S, Musat N, Richnow HH, Schmidt M. Tracking deuterium uptake in hydroponically grown maize roots using correlative helium ion microscopy and Raman micro-spectroscopy. PLANT METHODS 2023; 19:71. [PMID: 37452400 PMCID: PMC10347822 DOI: 10.1186/s13007-023-01040-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 06/19/2023] [Indexed: 07/18/2023]
Abstract
BACKGROUND Investigations into the growth and self-organization of plant roots is subject to fundamental and applied research in various areas such as botany, agriculture, and soil science. The growth activity of the plant tissue can be investigated by isotope labeling experiments with heavy water and subsequent detection of the deuterium in non-exchangeable positions incorporated into the plant biomass. Commonly used analytical methods to detect deuterium in plants are based on mass-spectrometry or neutron-scattering and they either suffer from elaborated sample preparation, destruction of the sample during analysis, or low spatial resolution. Confocal Raman micro-spectroscopy (CRM) can be considered a promising method to overcome the aforementioned challenges. The substitution of hydrogen with deuterium results in the measurable shift of the CH-related Raman bands. By employing correlative approaches with a high-resolution technique, such as helium ion microscopy (HIM), additional structural information can be added to CRM isotope maps and spatial resolution can be further increased. For that, it is necessary to develop a comprehensive workflow from sample preparation to data processing. RESULTS A workflow to prepare and analyze roots of hydroponically grown and deuterium labeled Zea mays by correlative HIM-CRM micro-analysis was developed. The accuracy and linearity of deuterium detection by CRM were tested and confirmed with samples of deuterated glucose. A set of root samples taken from deuterated Zea mays in a time-series experiment was used to test the entire workflow. The deuterium content in the roots measured by CRM was close to the values obtained by isotope-ratio mass spectrometry. As expected, root tips being the most actively growing root zone had incorporated the highest amount of deuterium which increased with increasing time of labeling. Furthermore, correlative HIM-CRM analysis allowed for obtaining the spatial distribution pattern of deuterium and lignin in root cross-sections. Here, more active root zones with higher deuterium incorporation showed less lignification. CONCLUSIONS We demonstrated that CRM in combination with deuterium labeling can be an alternative and reliable tool for the analysis of plant growth. This approach together with the developed workflow has the potential to be extended to complex systems such as plant roots grown in soil.
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Affiliation(s)
- Yalda Davoudpour
- Department of Isotope Biogeochemistry, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany.
| | - Steffen Kümmel
- Department of Isotope Biogeochemistry, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Niculina Musat
- Department of Isotope Biogeochemistry, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Hans Hermann Richnow
- Department of Isotope Biogeochemistry, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Matthias Schmidt
- Department of Isotope Biogeochemistry, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany
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Evans BR, Foston M, O'Neill HM, Reeves D, Rempe C, McGrath K, Ragauskas AJ, Davison BH. Production of deuterated biomass by cultivation of Lemna minor (duckweed) in D 2O. PLANTA 2019; 249:1465-1475. [PMID: 30697645 DOI: 10.1007/s00425-019-03097-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 01/21/2019] [Indexed: 06/09/2023]
Abstract
Common duckweed Lemna minor was cultivated in 50% D2O to produce biomass with 50-60% deuterium incorporation containing cellulose with degree of polymerization close (85%) to that of H2O-grown controls. The small aquatic plant duckweed, particularly the genus Lemna, widely used for toxicity testing, has been proposed as a potential source of biomass for conversion into biofuels as well as a platform for production of pharmaceuticals and specialty chemicals. Ability to produce deuterium-substituted duckweed can potentially extend the range of useful products as well as assist process improvement. Cultivation of these plants under deuterating conditions was previously been reported to require addition of kinetin to induce growth and was hampered by anomalies in cellular morphology and protein metabolism. Here, we report the production of biomass with 50-60% deuterium incorporation by long-term photoheterotrophic growth of common duckweed Lemna minor in 50% D2O with 0.5% glucose. L. minor grown in 50% D2O without addition of kinetin exhibited a lag phase twice that of H2O-grown controls, before start of log phase growth at 40% of control rates. Compared to continuous white fluorescent light, growth rates increased fivefold for H2O and twofold for 50% D2O when plants were illuminated at higher intensity with a metal halide lamp and a diurnal cycle of 12-h light/12-h dark. Deuterium incorporation was determined by a combination of 1H and 2H nuclear magnetic resonance (NMR) to be 40-60%. The cellulose from the deuterated plants had an average-number degree of polymerization (DPn) and polydispersity index (PDI) close to that of H2O-grown controls, while Klason lignin content was reduced. The only major gross morphological change noted was root inhibition.
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Affiliation(s)
- Barbara R Evans
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
| | - Marcus Foston
- Institute of Paper Science and Technology, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332, USA
- Department of Energy, Environmental and Chemical Engineering, Washington University, St. Louis, MO, 63130, USA
| | - Hugh M O'Neill
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - David Reeves
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
- Bredesen Center for Interdisciplinary Research and Graduate Education, University of Tennessee, Knoxville, TN, 37996, USA
| | - Caroline Rempe
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
- School of Genome Science and Technology, F337 Walters Life Science, University of Tennessee, Knoxville, 37996, TN, USA
| | - Kathi McGrath
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
- Sierra Vista High School, Las Vegas, NV, USA
| | - Arthur J Ragauskas
- Institute of Paper Science and Technology, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332, USA
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN, 37996, USA
| | - Brian H Davison
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
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Bhagia S, Pu Y, Evans BR, Davison BH, Ragauskas AJ. Hemicellulose characterization of deuterated switchgrass. BIORESOURCE TECHNOLOGY 2018; 269:567-570. [PMID: 30145003 DOI: 10.1016/j.biortech.2018.08.034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 08/08/2018] [Accepted: 08/09/2018] [Indexed: 06/08/2023]
Abstract
This work describes the structural characterization of hemicellulose isolated from hydroponically grown switchgrass in H2O medium (protiated) or 50% D2O medium (deuterated) through compositional analysis, GPC, FTIR, 13C and 1H/13C HSQC NMR. 4-O-methyl glucuronoarabinoxylan (GAX), the major hemicellulose in switchgrass isolated from deuterated switchgrass, had structural properties similar to hemicellulose isolated from protiated switchgrass. Both had comparable arabinose to xylose ratio (0.25) and molecular weight (47-50 kDa). Structural similarities show that deuterated switchgrass hemicellulose can be used as a model carbohydrate polymer in neutron scattering, or pharmaceutical studies due to their immunomodulatory activity and gastroprotective effects.
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Affiliation(s)
- Samarthya Bhagia
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996, USA
| | - Yunqiao Pu
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; Joint Institute of Biological Sciences, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Barbara R Evans
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Brian H Davison
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Arthur J Ragauskas
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996, USA; Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; Joint Institute of Biological Sciences, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; Center for Renewable Carbon, Department of Forestry, Wildlife, and Fisheries, University of Tennessee Institute of Agriculture, Knoxville, TN 37996, USA.
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Bhagia S, Meng X, Evans BR, Dunlap JR, Bali G, Chen J, Reeves KS, Ho HC, Davison BH, Pu Y, Ragauskas AJ. Ultrastructure and Enzymatic Hydrolysis of Deuterated Switchgrass. Sci Rep 2018; 8:13226. [PMID: 30185812 PMCID: PMC6125453 DOI: 10.1038/s41598-018-31269-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 08/07/2018] [Indexed: 01/01/2023] Open
Abstract
Neutron scattering of deuterated plants can provide fundamental insight into the structure of lignocellulosics in plant cell walls and its deconstruction by pretreatment and enzymes. Such plants need to be characterized for any alterations to lignocellulosic structure caused by growth in deuterated media. Here we show that glucose yields from enzymatic hydrolysis at lower enzyme loading were 35% and 30% for untreated deuterated and protiated switchgrass, respectively. Lignin content was 4% higher in deuterated switchgrass but there were no significant lignin structural differences. Transmission electron microscopy showed differences in lignin distribution and packing of fibers in the cell walls that apparently increased surface area of cellulose in deuterated switchgrass, increasing cellulose accessibility and lowering its recalcitrance. These differences in lignification were likely caused by abiotic stress due to growth in deuterated media.
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Affiliation(s)
- Samarthya Bhagia
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN, 37996, USA
| | - Xianzhi Meng
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN, 37996, USA
| | - Barbara R Evans
- Chemical Sciences Division, Oak Ridge National Laboratory**, Oak Ridge, TN, 37831, USA
| | - John R Dunlap
- Advanced Microscopy and Imaging Center, University of Tennessee, Knoxville, TN, 37996, USA
| | - Garima Bali
- Renewable Bioproducts Institute, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Jihua Chen
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Kimberly Shawn Reeves
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Hoi Chun Ho
- Carbon and Composite Group, Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
- The Bredesen Center for Interdisciplinary Research and Graduate Education, The University of Tennessee, Knoxville, TN, 37996, USA
| | - Brian H Davison
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Yunqiao Pu
- Joint Institute of Biological Sciences, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Arthur J Ragauskas
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN, 37996, USA.
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
- Joint Institute of Biological Sciences, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
- Center for Renewable Carbon, Department of Forestry, Wildlife, and Fisheries, University of Tennessee Institute of Agriculture, Knoxville, TN, 37996, USA.
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Abstract
Dynamic neutron scattering directly probes motions in biological systems on femtosecond to microsecond timescales. When combined with molecular dynamics simulation and normal mode analysis, detailed descriptions of the forms and frequencies of motions can be derived. We examine vibrations in proteins, the temperature dependence of protein motions, and concepts describing the rich variety of motions detectable using neutrons in biological systems at physiological temperatures. New techniques for deriving information on collective motions using coherent scattering are also reviewed.
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Affiliation(s)
- Jeremy C Smith
- UT/ORNL Center for Molecular Biophysics, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6309, USA; .,Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Pan Tan
- School of Physics and Astronomy and Institute of Natural Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Loukas Petridis
- UT/ORNL Center for Molecular Biophysics, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6309, USA; .,Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Liang Hong
- School of Physics and Astronomy and Institute of Natural Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
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Vergara F, Itouga M, Becerra RG, Hirai M, Ordaz-Ortiz JJ, Winkler R. Funaria hygrometrica Hedw. elevated tolerance to D 2O: its use for the production of highly deuterated metabolites. PLANTA 2018; 247:405-412. [PMID: 29030693 DOI: 10.1007/s00425-017-2794-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 10/08/2017] [Indexed: 06/07/2023]
Abstract
The method introduced here to grow F. hygrometrica in high concentrations of D 2 O is an excellent alternative to produce highly deuterated metabolites with broad applications in metabolic studies. Our mass spectrometry experiments strongly indicate the successful incorporation of deuterium into organic compounds. Deuterated metabolites are useful tracers for metabolic studies, yet their wide utilization in research is limited by the multi-step total synthesis required to produce them in the laboratory. Alternatively, deuterated metabolites can be obtained from organisms grown in D2O or deuterated nutrients. This approach also has limitations as D2O in high concentrations negatively affects the survival of most organisms. Here we report the moss Funaria hygrometrica as an unusual high tolerant to D2O in liquid culture. We found that this moss is able to grow in up to 90% D2O, a condition lethal for many eukaryotes. Mass spectrometric analyses of F. hygrometrica extracts showed a strong deuteration pattern. The ability to tolerate high concentrations of D2O together with the development of a rich molecular toolbox makes F. hygrometrica an ideal system for the production of valuable deuterated metabolites.
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Affiliation(s)
- Fredd Vergara
- Metabolic Systems Research Team, RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan.
| | - Misao Itouga
- Plant Productivity Systems Research Group, RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama, Japan
| | - Roberto Gamboa Becerra
- National Laboratory of Genomics for Biodiversity, CINVESTAV Unidad Irapuato, Irapuato, Mexico
| | - Masami Hirai
- Metabolic Systems Research Team, RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan
| | - José Juan Ordaz-Ortiz
- National Laboratory of Genomics for Biodiversity, CINVESTAV Unidad Irapuato, Irapuato, Mexico
| | - Robert Winkler
- Department of Biotechnology and Biochemistry, CINVESTAV Unidad Irapuato, Irapuato, Mexico
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Abstract
Soon after the discovery of deuterium, efforts to utilize this stable isotope of hydrogen for labeling of plants began and have proven successful for natural abundance to 20% enrichment. However, isotopic labeling with deuterium ((2)H) in higher plants at the level of 40% and higher is complicated by both physiological responses, particularly water exchange through transpiration, and inhibitory effects of D2O on germination, rooting, and growth. The highest incorporation of 40-50% had been reported for photoheterotrophic cultivation of the duckweed Lemna. Higher substitution is desirable for certain applications using neutron scattering and nuclear magnetic resonance (NMR) techniques. (1)H(2)H NMR and mass spectroscopy are standard methods frequently used for determination of location and amount of deuterium substitution. The changes in infrared (IR) absorption observed for H to D substitution in hydroxyl and alkyl groups provide rapid initial evaluation of incorporation. Short-term experiments with cold-tolerant annual grasses can be carried out in enclosed growth containers to evaluate incorporation. Growth in individual chambers under continuous air perfusion with dried sterile-filtered air enables long-term cultivation of multiple plants at different D2O concentrations. Vegetative propagation from cuttings extends capabilities to species with low germination rates. Cultivation in 50% D2O of annual ryegrass and switchgrass following establishment of roots by growth in H2O produces samples with normal morphology and 30-40% deuterium incorporation in the biomass. Winter grain rye (Secale cereale) was found to efficiently incorporate deuterium by photosynthetic fixation from 50% D2O but did not incorporate deuterated phenylalanine-d8 from the growth medium.
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Affiliation(s)
- Barbara R Evans
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.
| | - Riddhi Shah
- Bredesen Center for Interdisciplinary Research and Graduate Education, University of Tennessee, Knoxville, Tennessee, USA; Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
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