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Zhao Y, Yang H, Yan Q, Zhu Z, Wang B, Song Z, Hou S, Zhou Y. n-Alkane 13C/12C indicates differential metabolic controls of fatty lipid chain extension in C3 and C4 grasses. PLANT PHYSIOLOGY 2024; 194:1299-1303. [PMID: 37988573 DOI: 10.1093/plphys/kiad619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 10/03/2023] [Accepted: 10/25/2023] [Indexed: 11/23/2023]
Abstract
Fundamental differences in metabolic control of fatty acids chain extension are reflected in the contrasting carbon isotopic composition profiles of C3 and C4 grasses.
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Affiliation(s)
- Yu Zhao
- Isotopomics in Chemical Biology (ICB), School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Xi'an 710021, China
| | - Hubiao Yang
- Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China
| | - Qiulin Yan
- Isotopomics in Chemical Biology (ICB), School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Xi'an 710021, China
| | - Zhenyu Zhu
- Isotopomics in Chemical Biology (ICB), School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Xi'an 710021, China
| | - Bo Wang
- Isotopomics in Chemical Biology (ICB), School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Xi'an 710021, China
| | | | - Shengwei Hou
- Department of Ocean Science & Engineering, Southern University of Science & Technology, Shenzhen 518055, China
| | - Youping Zhou
- Department of Ocean Science & Engineering, Southern University of Science & Technology, Shenzhen 518055, China
- Isotopomics in Chemical Biology (ICB), School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Xi'an 710021, China
- Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
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2
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Sun Y, Ruiz Orduna A, Zhang Z, Feakins SJ, Jetter R. Biosynthesis of barley wax β-diketones: a type-III polyketide synthase condensing two fatty acyl units. Nat Commun 2023; 14:7284. [PMID: 37949901 PMCID: PMC10638390 DOI: 10.1038/s41467-023-42917-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 10/25/2023] [Indexed: 11/12/2023] Open
Abstract
The surface coatings of cereal plants are dominated by waxy β-diketones crucial for drought resistance and, therefore, grain yield. Here, barley (Hordeum vulgare) wax analyses reveal β-diketone and associated 2-alkanol ester profiles suggesting a common C16 3-ketoacid precursor. Isotope analysis further shows that the major (C31) diketone is synthesized from two plastidial C16 acyl units. Previous studies identified a gene cluster encoding enzymes responsible for β-diketone formation in barley, but left their biochemical functions unknown. Various assays now characterize one of these enzymes as a thioesterase producing long-chain (mainly C16) 3-ketoacids, and another one as a polyketide synthase (PKS) condensing the 3-ketoacids with long-chain (mainly C16) acyl-CoAs into β-diketones. The two enzymes are localized to the plastids and Endoplasmic Reticulum (ER), respectively, implying substrate transfer between these two sub-cellular compartments. Overall, our findings define a two-step pathway involving an unprecedented PKS reaction leading directly to the β-diketone products.
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Affiliation(s)
- Yulin Sun
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Alberto Ruiz Orduna
- Department of Chemistry, University of British Columbia, Vancouver, BC, V6T 1Z1, Canada
| | - Zhonghang Zhang
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Sarah J Feakins
- Department of Earth Sciences, University of Southern California, 3651 Trousdale Pkwy, Los Angeles, CA, 90089, USA
| | - Reinhard Jetter
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.
- Department of Chemistry, University of British Columbia, Vancouver, BC, V6T 1Z1, Canada.
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3
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Gozdzik J, Busta L, Jetter R. Leaf cuticular waxes of wild-type Welsh onion (Allium fistulosum L.) and a wax-deficient mutant: Compounds with terminal and mid-chain functionalities. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 198:107679. [PMID: 37121165 DOI: 10.1016/j.plaphy.2023.107679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 03/21/2023] [Accepted: 04/02/2023] [Indexed: 05/02/2023]
Abstract
Plant cuticles cover aerial organs to limit non-stomatal water loss and protect against insects and pathogens. Cuticles contain complex mixtures of fatty acid-derived waxes, with various chain lengths and diverse functional groups. To further our understanding of the chemical diversity and biosynthesis of these compounds, this study investigated leaf cuticular waxes of Welsh onion (Allium fistulosum L.) wild type and a wax-deficient mutant. Leaf waxes were extracted with chloroform, separated using thin layer chromatography (TLC), and analyzed using gas chromatography-mass spectrometry (GC-MS). The extracts contained typical wax compound classes found in nearly all plant lineages but also two uncommon compound classes. Analyses of characteristic MS fragmentation patterns followed by comparisons with synthetic standards identified the latter as very-long-chain ketones and primary ketols. The ketols were minor compounds, with chain lengths ranging from C28 to C32 and carbonyls mainly on C-18 and C-20 in wild type wax, and a C28 chain with C-16 carbonyl in the mutant. The ketones made up 70% of total wax in the wild type, consisting mainly of C31 isomers with carbonyl group on C-14 or C-16. In contrast, the mutant wax comprised only 4% ketones, with chain lengths C27 and C29 and carbonyls predominantly on C-12 and C-14, respectively. A two-carbon homolog shift between wild type and mutant was also observed in the primary alcohols (a major wax compound class), whilst alkanes exhibited a four-carbon shift. Overall, the compositional data shed light on possible biosynthetic pathways to wax ketones that can be tested in future studies.
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Affiliation(s)
- Jedrzej Gozdzik
- Department of Chemistry, University of British Columbia, Vancouver, BC, V6T 1Z1, Canada
| | - Lucas Busta
- Department of Chemistry and Biochemistry, University of Minnesota Duluth, Duluth, MN, 55812, USA
| | - Reinhard Jetter
- Department of Chemistry, University of British Columbia, Vancouver, BC, V6T 1Z1, Canada; Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.
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Baan J, Holloway-Phillips M, Nelson DB, Kahmen A. The metabolic sensitivity of hydrogen isotope fractionation differs between plant compounds. PHYTOCHEMISTRY 2023; 207:113563. [PMID: 36528118 DOI: 10.1016/j.phytochem.2022.113563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 12/10/2022] [Accepted: 12/11/2022] [Indexed: 06/17/2023]
Abstract
Hydrogen stable isotope analyses (δ2H) of plant derived organic compounds are a useful tool for ecological, environmental, and palaeoclimatological research. However, during organic compound synthesis, variable biosynthetic 2H-fractionation has been suggested to occur as a result of changes in plant carbon fluxes. So far, inference has been based on examining the δ2H patterns of plant compounds along environmental gradients, among plant species, and between plant organs. In an alternative approach, we used four plant species with four different types of mutations that cause impaired starch synthesis to assess whether variability in carbon metabolism affects the biosynthetic 2H-fractionation during cellulose, phytol, and acetogenic lipid synthesis. We found that mutants with impaired starch synthesis always had higher cellulose and phytol δ2H values compared to the wild type. By contrast, 2H-fractionation during acetogenic lipid biosynthesis generally did not show strong metabolic sensitivity. We rationalise these differences by considering the biosynthetic pathway of each compound and the likely source of the variable isotope fractionation. In different organic compounds, the sensitivity of variable biosynthetic 2H-fractionation to changes in C-metabolism depends on incorporation of specific H atoms from precursor molecules. As such, we determined that the similar increase in cellulose and phytol δ2H values as an effect of impaired starch synthesis most likely originates in triose-phosphates.
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Affiliation(s)
- Jochem Baan
- University of Basel, Department of Environmental Sciences - Botany, Schönbeinstrasse 6, 4056, Basel, Switzerland.
| | - Meisha Holloway-Phillips
- University of Basel, Department of Environmental Sciences - Botany, Schönbeinstrasse 6, 4056, Basel, Switzerland
| | - Daniel B Nelson
- University of Basel, Department of Environmental Sciences - Botany, Schönbeinstrasse 6, 4056, Basel, Switzerland
| | - Ansgar Kahmen
- University of Basel, Department of Environmental Sciences - Botany, Schönbeinstrasse 6, 4056, Basel, Switzerland
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5
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Zhu Z, Yin X, Song X, Wang B, Ma R, Zhao Y, Rani A, Wang Y, Yan Q, Jing S, Gessler A, Zhou Y. Leaf transition from heterotrophy to autotrophy is recorded in the intraleaf C, H and O isotope patterns of leaf organic matter. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2020; 34:e8840. [PMID: 32441059 DOI: 10.1002/rcm.8840] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 05/14/2020] [Accepted: 05/17/2020] [Indexed: 06/11/2023]
Abstract
RATIONALE Quantitatively relating 13 C/12 C, 2 H/1 H and 18 O/16 O ratios of plant α-cellulose and 2 H/1 H of n-alkanes to environmental conditions and metabolic status should ideally be based on the leaf, the plant organ most sensitive to environmental change. The fact that leaf organic matter is composed of isotopically different heterotrophic and autotrophic components means that it is imperative that one be able to disentangle the relative heterotrophic and autotrophic contributions to leaf organic matter. METHODS We tackled this issue by two-dimensional sampling of leaf water and α-cellulose, and specific n-alkanes from greenhouse-grown immature and mature and field-grown mature banana leaves, taking advantage of their large areas and thick waxy layers. Leaf water, α-cellulose and n-alkane isotope ratios were then characterized using elemental analysis isotope ratio mass spectrometry (IRMS) or gas chromatography IRMS. A three-member (heterotrophy, autotrophy and photoheterotrophy) conceptual linear mixing model was then proposed for disentangling the relative contributions of the three trophic modes. RESULTS We discovered distinct spatial leaf water, α-cellulose and n-alkane isotope ratio patterns that varied with leaf developmental stages. We inferred from the conceptual model that, averaged over the leaf blade, only 20% of α-cellulose in banana leaf is autotrophically laid down in both greenhouse-grown and field-grown banana leaves, while approximately 60% and 100% of n-alkanes are produced autotrophically in greenhouse-grown and field-grown banana leaves, respectively. There exist distinct lateral (edge to midrib) gradients in autotrophic contributions of α-cellulose and n-alkanes. CONCLUSIONS Efforts to establish quantitative isotope-environment relationships should take into account the fact that the evaporative leaf water 18 O and 2 H enrichment signal recorded in autotrophically laid down α-cellulose is significantly diluted by the heterotrophically formed α-cellulose. The δ2 H value of field-grown mature banana leaf n-alkanes is much more sensitive than α-cellulose as a recorder of the growth environment. Quantitative isotope-environment relationship based on greenhouse-grown n-alkane δ2 H values may not be reliable.
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Affiliation(s)
- Zhenyu Zhu
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
| | - Xijie Yin
- Laboratory of Marine & Coastal Geology, MNR Third Institute of Oceanology, 178 Daxue Road, Xiamen, 361005, China
| | - Xin Song
- School of Life and Marine Sciences, Shenzhen University, 3688 Nanhai Road, Shenzhen, 518060, China
| | - Bo Wang
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
| | - Ran Ma
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
| | - Yu Zhao
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
| | - Andleeb Rani
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
| | - Ying Wang
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
| | - Qiulin Yan
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
| | - Su Jing
- Laboratory of Marine & Coastal Geology, MNR Third Institute of Oceanology, 178 Daxue Road, Xiamen, 361005, China
| | - Arthur Gessler
- Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, 8903, Switzerland
| | - Youping Zhou
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
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6
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Zhu Z, Yin X, Lu F, Wang B, Ma R, Zhao Y, Wang Y, Ma Y, Su J, Yan Q, Hocart CH, Zhou Y. The effect of processing medium on the 2 H/ 1 H of carbon-bound hydrogen in α-cellulose extracted from higher plants. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2020; 34:e8641. [PMID: 31965648 DOI: 10.1002/rcm.8641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 10/21/2019] [Accepted: 10/21/2019] [Indexed: 06/10/2023]
Abstract
RATIONALE Although the 2 H/1 H ratio of the carbon-bound hydrogens (C-Hs) in α-cellulose extracted from higher plants has long been used successfully for climate, environmental and metabolic studies, the assumption that bleaching with acidified NaClO2 to remove lignin before pure α-cellulose can be obtained does not alter the 2 H/1 H ratio of α-cellulose C-Hs has nonetheless not been tested. METHODS For reliable application of the 2 H/1 H ratio of α-cellulose C-H, we processed plant materials representing different phytochemistries and photosynthetic carbon assimilation modes in isotopically contrasting bleaching media (with an isotopic difference of 273 mUr). All the isotope ratios were measured by elemental analyzer/isotope ratio mass spectrometry (EA/IRMS). RESULTS Our results show that H from the bleaching medium does appear in the final pure α-cellulose product, although the isotopic alteration to the C-H in α-cellulose due to the incorporation of processing H from the medium is small if isotopically "natural" water is used to prepare the processing medium. However, under prolonged bleaching such an isotope effect can be significant, implying that standardizing the bleaching process is necessary for reliable 2 H/1 H measurement. CONCLUSIONS The currently adopted method for removing lignin for α-cellulose extraction from higher plant materials with acidified NaClO2 bleaching is considered acceptable in terms of preserving the isotopic fidelity if isotopically "natural" water is used to prepare the bleaching solution.
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Affiliation(s)
- Zhenyu Zhu
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
- Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, 519000, China
| | - Xijie Yin
- Laboratory of Marine & Coastal Geology, MNR Third Institute of Oceanology, Xiamen, 361005, China
| | - Fengyan Lu
- Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China
| | - Bo Wang
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
| | - Ran Ma
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
| | - Yu Zhao
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
| | - Ying Wang
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
| | - Yi Ma
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
| | - Jing Su
- Laboratory of Marine & Coastal Geology, MNR Third Institute of Oceanology, Xiamen, 361005, China
| | - Qiulin Yan
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
| | - Charles H Hocart
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
- Research School of Biology, Australian National University, Canberra, 2601, Australia
| | - Youping Zhou
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Weiyang University Park, Xi'an, 710021, China
- Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, 519000, China
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Ma R, Zhao Y, Liu L, Zhu Z, Wang B, Wang Y, Yin X, Su J, Zhou Y. Novel Position-Specific 18O/ 16O Measurement of Carbohydrates. II. The Complete Intramolecular 18O/ 16O Profile of the Glucose Unit in a Starch of C4 Origin. Anal Chem 2020; 92:7462-7470. [PMID: 32365292 DOI: 10.1021/acs.analchem.9b05314] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Information about plant photosynthetic carbon assimilation, physiology, and biochemistry is locked in the 18O/16O ratios of the individual positions of higher plants carbohydrates but is under-utilized, because of the difficulty of making these determinations. We report the extension of the wet chemistry approach we used to access the 18O/16O ratio of O-3 of glucose with a novel GC/Pyrolysis/IRMS-based method, to determine the 18O/16O ratios of O-4, O-5, and O-6. The O atoms (OH groups) at positions 1, 2, 5, and 6 of glucose were protected by acetonation (converting to 1,2;5,6-di-O-isopropylidene-glucofuranose, DAGF). The DAGF was then converted to 6-bromo-6-deoxy-1,2;3,5-di-O-isopropylidene-glucofuranose (6-bromoDAGF) with the simultaneous removal of O-6 with N-bromosuccinimide and triphenylphosphine. The DAGF was also methylated at O-3 with CH3I under the catalysis of NaH to 3-methylDAGF, which was then deacetonated to 1,2-O-isopropylidene-3-O-methyl-glucofuranose (3-methylMAGF). O-5 and O-6 were then removed as a whole from 3-methylMAGF by I2 oxidization under the catalysis of Ph3P and imidazole. Isotope mass balance was then applied to calculate the 18O/16O of O-5 and O-6 as a whole and O-6, respectively. Sampling at different stages of substrate conversion to product and applying a Rayleigh-type fractionation model were employed, when quantitative conversion of substrate was unachievable to calculate the δ18O of the converted substrate. Quantitative conversion of glucose with phenylhydrazine to phenylglucosazone also allowed for the calculation of δ18O2 by applying isotope mass balance between the two. A C4 starch-derived glucose intramolecular δ18O profile is now determined: O-3 is relatively enriched (by 12.16 mUr), O-4 is relatively depleted (by 20.40-31.11 mUr), and O-2 is marginally enriched (by 2.40 mUr) against the molecular average.
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Affiliation(s)
- Ran Ma
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Xi'an, China, 710021
| | - Yu Zhao
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Xi'an, China, 710021
| | - Lan Liu
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Xi'an, China, 710021.,Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, China, 519082
| | - Zhenyu Zhu
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Xi'an, China, 710021
| | - Bo Wang
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Xi'an, China, 710021
| | - Ying Wang
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Xi'an, China, 710021
| | - Xijie Yin
- MNR Third Institute of Oceanology, Xiamen, China, 361005
| | - Jing Su
- MNR Third Institute of Oceanology, Xiamen, China, 361005
| | - Youping Zhou
- Isotopomics in Chemical Biology & Shaanxi Key Laboratory of Chemical Additives for Industry, School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Xi'an, China, 710021.,Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, China, 519082
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8
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Liu J, An Z. Variations in hydrogen isotopic fractionation in higher plants and sediments across different latitudes: Implications for paleohydrological reconstruction. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 650:470-478. [PMID: 30199691 DOI: 10.1016/j.scitotenv.2018.09.047] [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: 05/16/2018] [Revised: 09/03/2018] [Accepted: 09/04/2018] [Indexed: 06/08/2023]
Abstract
Sedimentary δDn-alkane value is widely utilized as a reliable proxy for paleo-hydrological reconstruction. Applications of this proxy must be based upon a globally clear understanding of the relationship between leaf wax δDn-alkane values and precipitation δD (δDp), defined as apparent fractionation (εapp). However, there is a critical concern about whether relatively constant εapp values exist across different latitudes. In this study, we systematically analyzed the variations of available εapp with latitudes based upon two compiled-new databases of higher plants and sediments over the world. We found that the total average εapp was relatively constant, i.e., -116 ± 5‰ (n = 941), in higher plants across different latitudes without consideration of plant types (e.g., dicots, monocots, gymnosperms), and was still constant but slightly lower average εapp, i.e., -125 ± 6‰ (n = 460), in sediments across the latitudes. The slightly lower average εapp in sediments relative to higher plants probably derived from the contribution of aquatic plants with isotopically D-depleted εapp in lake sediments. Interestingly, with consideration of plant types, average εapp increased in dicots but decreased in monocots slightly from low to high latitudes. The counteraction of these competing trends generates relatively constant average εapp values in higher plants, and resultantly constant average εapp values occur in sediments at the global scale. It is important to elaborate relatively constant εapp values from higher plants and sediments across different latitudes when sedimentary δDn-alkane is utilized as a proxy for paleohydrological reconstruction.
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Affiliation(s)
- Jinzhao Liu
- State key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
| | - Zhisheng An
- State key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
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9
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Distinctions in heterotrophic and autotrophic-based metabolism as recorded in the hydrogen and carbon isotope ratios of normal alkanes. Oecologia 2018; 187:1053-1075. [DOI: 10.1007/s00442-018-4189-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Accepted: 06/05/2018] [Indexed: 10/28/2022]
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10
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Zhou Y, Zhang B, Stuart-Williams H, Grice K, Hocart CH, Gessler A, Kayler ZE, Farquhar GD. On the contributions of photorespiration and compartmentation to the contrasting intramolecular 2H profiles of C 3 and C 4 plant sugars. PHYTOCHEMISTRY 2018; 145:197-206. [PMID: 29175728 DOI: 10.1016/j.phytochem.2017.11.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Accepted: 11/03/2017] [Indexed: 06/07/2023]
Abstract
Compartmentation of C4 photosynthetic biochemistry into bundle sheath (BS) and mesophyll (M) cells, and photorespiration in C3 plants is predicted to have hydrogen isotopic consequences for metabolites at both molecular and site-specific levels. Molecular-level evidence was recently reported (Zhou et al., 2016), but evidence at the site-specific level is still lacking. We propose that such evidence exists in the contrasting 2H distribution profiles of glucose samples from naturally grown C3, C4 and CAM plants: photorespiration contributes to the relative 2H enrichment in H5 and relative 2H depletion in H1 & H6 (the average of the two pro-chiral Hs and in particular H6,pro-R) in C3 glucose, while 2H-enriched C3 mesophyll cellular (chloroplastic) water most likely contributes to the enrichment at H4; export of (transferable hydrogen atoms of) NADPH from C4 mesophyll cells to bundle sheath cells (via the malate shuttle) and incorporation of 2H-relatively unenriched BS cellular water contribute to the relative depletion of H4 & H5 respectively; shuttling of triose-phosphates (PGA: phosphoglycerate dand DHAP: dihydroacetone phosphate) between C4 bundle sheath and mesophyll cells contributes to the relative enrichment in H1 & H6 (in particular H6,pro-R) in C4 glucose.
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Affiliation(s)
- Youping Zhou
- School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Xi'an, China; Institute for Landscape Biogeochemistry, ZALF, Germany; Leibniz Institute for Freshwater Ecology & Inland Fisheries, Germany.
| | - Benli Zhang
- School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Xi'an, China
| | | | - Kliti Grice
- WA-Organic and Isotope Geochemistry Centre, Department of Chemistry, Curtin University, Australia
| | - Charles H Hocart
- School of Chemistry & Chemical Engineering, Shaanxi University of Science & Technology, Xi'an, China; Research School of Biology, Australian National University, Australia
| | - Arthur Gessler
- Institute for Landscape Biogeochemistry, ZALF, Germany; Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, Switzerland
| | - Zachary E Kayler
- Institute for Landscape Biogeochemistry, ZALF, Germany; USDA Forest Service, Northern Research Station, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA
| | - Graham D Farquhar
- Research School of Biology, Australian National University, Australia
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Zhou Y, Grice K, Stuart-Williams H, Hocart CH, Gessler A, Farquhar GD. Hydrogen isotopic differences between C 3 and C 4 land plant lipids: consequences of compartmentation in C 4 photosynthetic chemistry and C 3 photorespiration. PLANT, CELL & ENVIRONMENT 2016; 39:2676-2690. [PMID: 27566133 DOI: 10.1111/pce.12821] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Accepted: 08/17/2016] [Indexed: 06/06/2023]
Abstract
The 2 H/1 H ratio of carbon-bound H in biolipids holds potential for probing plant lipid biosynthesis and metabolism. The biochemical mechanism underlying the isotopic differences between lipids from C3 and C4 plants is still poorly understood. GC-pyrolysis-IRMS (gas chromatography-pyrolysis-isotope ratio mass spectrometry) measurement of the 2 H/1 H ratio of leaf lipids from controlled and field grown plants indicates that the biochemical isotopic fractionation (ε2 Hlipid_biochem ) differed between C3 and C4 plants in a pathway-dependent manner: ε2 HC4 > ε2 HC3 for the acetogenic pathway, ε2 HC4 < ε2 HC3 for the mevalonic acid pathway and the 1-deoxy-D-xylulose 5-phosphate pathway across all species examined. It is proposed that compartmentation of photosynthetic CO2 fixation into C4 mesophyll (M) and bundle sheath (BS) cells and suppression of photorespiration in C4 M and BS cells both result in C4 M chloroplastic pyruvate - the precursor for acetogenic pathway - being more depleted in 2 H relative to pyruvate in C3 cells. In addition, compartmentation in C4 plants also results in (i) the transferable H of NADPH being enriched in 2 H in C4 M chloroplasts compared with that in C3 chloroplasts for the 1-deoxy-D-xylulose 5-phosphate pathway pathway and (ii) pyruvate relatively 2 H-enriched being used for the mevalonic acid pathway in the cytosol of BS cells in comparison with that in C3 cells.
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Affiliation(s)
- Youping Zhou
- School of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi'an, 710021, China
- WA-Organic and Isotope Geochemistry Centre, The Institute for Geoscience Research, Curtin University, Perth, 6845, Australia
- Institute for Landscape Biogeochemistry, ZALF, Müncheberg, 15374, Germany
- Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, China
| | - Kliti Grice
- WA-Organic and Isotope Geochemistry Centre, The Institute for Geoscience Research, Curtin University, Perth, 6845, Australia
| | | | - Charles H Hocart
- Research School of Biology, Australian National University, Canberra, 2601, Australia
| | - Arthur Gessler
- Institute for Landscape Biogeochemistry, ZALF, Müncheberg, 15374, Germany
- Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, 8903, Switzerland
| | - Graham D Farquhar
- Research School of Biology, Australian National University, Canberra, 2601, Australia
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12
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Pagès A, Grice K, Welsh DT, Teasdale PT, Van Kranendonk MJ, Greenwood P. Lipid Biomarker and Isotopic Study of Community Distribution and Biomarker Preservation in a Laminated Microbial Mat from Shark Bay, Western Australia. MICROBIAL ECOLOGY 2015; 70:459-472. [PMID: 25812998 DOI: 10.1007/s00248-015-0598-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 03/09/2015] [Indexed: 06/04/2023]
Abstract
Modern microbial mats from Shark Bay present some structural similarities with ancient stromatolites; thus, the functionality of microbial communities and processes of diagenetic preservation of modern mats may provide an insight into ancient microbial assemblages and preservation. In this study, the vertical distribution of microbial communities was investigated in a well-laminated smooth mat from Shark Bay. Biolipid and compound-specific isotopic analyses were performed to investigate the distribution of microbial communities in four distinct layers of the mat. Biomarkers indicative of cyanobacteria were more abundant in the uppermost oxic layer. Diatom markers (e.g. C25 HBI alkene, C20:4ω6 and C20:5ω3 polar lipid fatty acids (PLFAs)) were also detected in high abundance in the uppermost layer, but also in the deepest layer under conditions of permanent darkness and anoxia, where they probably used NO3 (-) for respiration. CycC19:0, an abundant PLFA of purple sulfur bacteria (PSB), was detected in all layers and presented the most (13)C-depleted values of all PLFAs, consistent with photoautotrophic PSB. Sulfur-bound aliphatic and aromatic biomarkers were detected in all layers, highlighting the occurrence of early sulfurisation which may be an important mechanism in the sedimentary preservation of functional biolipids in living and, thus, also ancient mats.
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Affiliation(s)
- Anais Pagès
- WA Organic and Isotope Geochemistry Centre, Department of Chemistry, The Institute for Geoscience Research, Curtin University, GPO Box U1987, Perth, Western Australia, 6845, Australia,
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13
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Tipple BJ, Berke MA, Hambach B, Roden JS, Ehleringer JR. Predicting leaf wax n-alkane 2H/1H ratios: controlled water source and humidity experiments with hydroponically grown trees confirm predictions of Craig-Gordon model. PLANT, CELL & ENVIRONMENT 2015; 38:1035-1047. [PMID: 25266328 DOI: 10.1111/pce.12457] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 09/11/2014] [Accepted: 09/23/2014] [Indexed: 06/03/2023]
Abstract
The extent to which both water source and atmospheric humidity affect δ(2)H values of terrestrial plant leaf waxes will affect the interpretations of δ(2)H variation of leaf waxes as a proxy for hydrological conditions. To elucidate the effects of these parameters, we conducted a long-term experiment in which we grew two tree species, Populus fremontii and Betula occidentalis, hydroponically under combinations of six isotopically distinct waters and two different atmospheric humidities. We observed that leaf n-alkane δ(2)H values of both species were linearly related to source water δ(2)H values, but with slope differences associated with differing humidities. When a modified version of the Craig-Gordon model incorporating plant factors was used to predict the δ(2)H values of leaf water, all modelled leaf water values fit the same linear relationship with n-alkane δ(2)H values. These observations suggested a relatively constant biosynthetic fractionation factor between leaf water and n-alkanes. However, our calculations indicated a small difference in the biosynthetic fractionation factor between the two species, consistent with small differences calculated for species in other studies. At present, it remains unclear if these apparent interspecies differences in biosynthetic fractionation reflect species-specific biochemistry or a common biosynthetic fractionation factor with insufficient model parameterization.
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Affiliation(s)
- Brett J Tipple
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA; Global Change and Sustainability Center, University of Utah, Salt Lake City, UT, 84112, USA
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14
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Zhou Y, Stuart-Williams H, Grice K, Kayler ZE, Zavadlav S, Vogts A, Rommerskirchen F, Farquhar GD, Gessler A. Allocate carbon for a reason: priorities are reflected in the ¹³C/¹²C ratios of plant lipids synthesized via three independent biosynthetic pathways. PHYTOCHEMISTRY 2015; 111:14-20. [PMID: 25576502 DOI: 10.1016/j.phytochem.2014.12.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Revised: 11/27/2014] [Accepted: 12/03/2014] [Indexed: 06/04/2023]
Abstract
It has long been theorized that carbon allocation, in addition to the carbon source and to kinetic isotopic effects associated with a particular lipid biosynthetic pathway, plays an important role in shaping the carbon isotopic composition ((13)C/(12)C) of lipids (Park and Epstein, 1961). If the latter two factors are properly constrained, valuable information about carbon allocation during lipid biosynthesis can be obtained from carbon isotope measurements. Published work of Chikaraishi et al. (2004) showed that leaf lipids isotopic shifts from bulk leaf tissue Δδ(13)C(bk-lp) (defined as δ(13)C(bulkleaftissue)-δ(13)C(lipid)) are pathway dependent: the acetogenic (ACT) pathway synthesizing fatty lipids has the largest isotopic shift, the mevalonic acid (MVA) pathway synthesizing sterols the lowest and the phytol synthesizing 1-deoxy-D-xylulose 5-phosphate (DXP) pathway gives intermediate values. The differences in Δδ(13)C(bk-lp) between C3 and C4 plants Δδ(13)C(bk-lp,C4-C3) are also pathway-dependent: Δδ(13)C(ACT)(bk-lp,C4-C3) > Δδ(13)C(DXP(bk-lp,C4-C3) > Δδ(13)C(MVA)(bk-lp,C4-C3). These pathway-dependent differences have been interpreted as resulting from kinetic isotopic effect differences of key but unspecified biochemical reactions involved in lipids biosynthesis between C3 and C4 plants. After quantitatively considering isotopic shifts caused by (dark) respiration, export-of-carbon (to sink tissues) and photorespiration, we propose that the pathway-specific differences Δδ(13)C(bk-lp,C4-C3) can be successfully explained by C4-C3 carbon allocation (flux) differences with greatest flux into the ACT pathway and lowest into the MVA pathways (when flux is higher, isotopic shift relative to source is smaller). Highest carbon allocation to the ACT pathway appears to be tied to the most stringent role of water-loss-minimization by leaf waxes (composed mainly of fatty lipids) while the lowest carbon allocation to the MVA pathway can be largely explained by the fact that sterols act as regulatory hormones and membrane fluidity modulators in rather low concentrations.
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Affiliation(s)
- Youping Zhou
- Institute for Landscape Biogeochemistry, ZALF, Germany; Department of Chemistry, Curtin University, Perth, Australia; SKLLQG, Chinese Academy of Sciences, Xi'an, China; Leibniz Institute for Freshwater Ecology & Inland Fisheries, Germany.
| | | | - Kliti Grice
- Department of Chemistry, Curtin University, Perth, Australia
| | | | | | - Angela Vogts
- Leibniz-Institut für Ostseeforschung, Rostock, Germany
| | | | | | - Arthur Gessler
- Institute for Landscape Biogeochemistry, ZALF, Germany; Swiss Federal Institute WSL, Birmensdorf, Switzerland
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15
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Larsen T, Ventura M, Andersen N, O’Brien DM, Piatkowski U, McCarthy MD. Tracing carbon sources through aquatic and terrestrial food webs using amino acid stable isotope fingerprinting. PLoS One 2013; 8:e73441. [PMID: 24069196 PMCID: PMC3775739 DOI: 10.1371/journal.pone.0073441] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 07/20/2013] [Indexed: 11/18/2022] Open
Abstract
Tracing the origin of nutrients is a fundamental goal of food web research but methodological issues associated with current research techniques such as using stable isotope ratios of bulk tissue can lead to confounding results. We investigated whether naturally occurring δ(13)C patterns among amino acids (δ(13)CAA) could distinguish between multiple aquatic and terrestrial primary production sources. We found that δ(13)CAA patterns in contrast to bulk δ(13)C values distinguished between carbon derived from algae, seagrass, terrestrial plants, bacteria and fungi. Furthermore, we showed for two aquatic producers that their δ(13)CAA patterns were largely unaffected by different environmental conditions despite substantial shifts in bulk δ(13)C values. The potential of assessing the major carbon sources at the base of the food web was demonstrated for freshwater, pelagic, and estuarine consumers; consumer δ(13)C patterns of essential amino acids largely matched those of the dominant primary producers in each system. Since amino acids make up about half of organismal carbon, source diagnostic isotope fingerprints can be used as a new complementary approach to overcome some of the limitations of variable source bulk isotope values commonly encountered in estuarine areas and other complex environments with mixed aquatic and terrestrial inputs.
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Affiliation(s)
- Thomas Larsen
- Leibniz-Laboratory for Radiometric Dating and Stable Isotope Research, Christian-Albrechts Universität zu Kiel, Kiel, Germany
- Biogeodynamics and Biodiversity Group, Centre for Advanced Studies of Blanes, Spanish Research Council (CEAB-CSIC), Blanes, Catalonia, Spain
| | - Marc Ventura
- Biogeodynamics and Biodiversity Group, Centre for Advanced Studies of Blanes, Spanish Research Council (CEAB-CSIC), Blanes, Catalonia, Spain
- Institut de Recerca de l’Aigua, Universitat de Barcelona, Barcelona, Catalonia, Spain
| | - Nils Andersen
- Leibniz-Laboratory for Radiometric Dating and Stable Isotope Research, Christian-Albrechts Universität zu Kiel, Kiel, Germany
| | - Diane M. O’Brien
- Institute of Arctic Biology and Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America
| | - Uwe Piatkowski
- GEOMAR, Helmholtz-Zentrum für Ozeanforschung Kiel, Kiel, Germany
| | - Matthew D. McCarthy
- Ocean Sciences Department, University of California Santa Cruz, Santa Cruz, California, United States of America
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Gilbert A, Robins RJ, Remaud GS, Tcherkez GGB. Intramolecular 13C pattern in hexoses from autotrophic and heterotrophic C3 plant tissues. Proc Natl Acad Sci U S A 2012; 109:18204-9. [PMID: 23074255 PMCID: PMC3497804 DOI: 10.1073/pnas.1211149109] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The stable carbon isotope (13)C is used as a universal tracer in plant eco-physiology and studies of carbon exchange between vegetation and atmosphere. Photosynthesis fractionates against (13)CO(2) so that source sugars (photosynthates) are on average (13)C depleted by 20‰ compared with atmospheric CO(2). The carbon isotope distribution within sugars has been shown to be heterogeneous, with relatively (13)C-enriched and (13)C-depleted C-atom positions. The (13)C pattern within sugars is the cornerstone of (13)C distribution in plants, because all metabolites inherit the (13)C abundance in their specific precursor C-atom positions. However, the intramolecular isotope pattern in source leaf glucose and the isotope fractionation associated with key enzymes involved in sugar interconversions are currently unknown. To gain insight into these, we have analyzed the intramolecular isotope composition in source leaf transient starch, grain storage starch, and root storage sucrose and measured the site-specific isotope fractionation associated with the invertase (EC 3.2.1.26) and glucose isomerase (EC 5.3.1.5) reactions. When these data are integrated into a simple steady-state model of plant isotopic fluxes, the enzyme-dependent fractionations satisfactorily predict the observed intramolecular patterns. These results demonstrate that glucose and sucrose metabolism is the primary determinant of the (13)C abundance in source and sink tissue and is, therefore, of fundamental importance to the interpretation of plant isotopic signals.
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Affiliation(s)
- Alexis Gilbert
- L'Université Nantes Angers Le Mans, Centre National de la Recherche Scientifique- University of Nantes Unité Mixte de Recherche 6230, F-44322 Nantes, France.
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Fatty and Volatile Oils of the Gypsywort Lycopus europaeus L. and the Gaussian-Like Distribution of its Wax Alkanes. J AM OIL CHEM SOC 2012. [DOI: 10.1007/s11746-012-2118-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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18
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Zhou Y, Stuart-Williams H, Farquhar GD, Hocart CH. The use of natural abundance stable isotopic ratios to indicate the presence of oxygen-containing chemical linkages between cellulose and lignin in plant cell walls. PHYTOCHEMISTRY 2010; 71:982-993. [PMID: 20362306 DOI: 10.1016/j.phytochem.2010.03.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2009] [Revised: 03/01/2010] [Accepted: 03/02/2010] [Indexed: 05/29/2023]
Abstract
Qualitative and quantitative understanding of the chemical linkages between the three major biochemical components (cellulose, hemicellulose and lignin) of plant cell walls is crucial to the understanding of cell wall structure. Although there is convincing evidence for chemical bonds between hemicellulose and lignin and the absence of chemical bonds between hemicellulose and cellulose, there is no conclusive evidence for the presence of covalent bonds between cellulose and lignin. This is caused by the lack of selectivity of current GC/MS-, NMR- and IR-based methods for lignin characterisation as none of these techniques directly targets the possible ester and ether linkages between lignin and cellulose. We modified the widely-accepted "standard" three-step extraction method for isolating cellulose from plants by changing the order of the steps for hemicellulose and lignin removal (solubilisation with concentrated NaOH and oxidation with acetic acid-containing NaClO(2), respectively) so that cellulose and lignin could be isolated with the possible chemical bonds between them intact. These linkages were then cleaved with NaClO(2) reagent in aqueous media of contrasting (18)O/(16)O ratios. We produced cellulose with higher purity (a lower level of residual hemicellulose and no detectable lignin) than that produced by the "standard" method. Oxidative artefacts may potentially be introduced at the lignin removal stage; but testing showed this to be minimal. Cellulose samples isolated from processing plant-derived cellulose-lignin mixtures in media of contrasting (18)O/(16)O ratios were compared to provide the first quantitative evidence for the presence of oxygen-containing ester and ether bonds between cellulose and lignin in Zea mays leaves. However, no conclusive evidence for the presence or lack of similar bonds in Araucaria cunninghamii wood was obtained.
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Affiliation(s)
- Youping Zhou
- Research School of Earth Sciences, Australian National University, Canberra, Australia.
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