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Gao M, Sun J, Xiao Q, Zhai Y, Tian Y, Zhang Z, Xu F, Zhang P. Sensitive quantification of mevalonate pathway intermediates and prediction of relative novel analogs by chemical derivatization-based LC-MS/MS. J Chromatogr A 2024; 1731:465163. [PMID: 39029328 DOI: 10.1016/j.chroma.2024.465163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 07/02/2024] [Accepted: 07/12/2024] [Indexed: 07/21/2024]
Abstract
The mevalonate (MVA) pathway plays a crucial role in the occurrence and progression of various diseases, such as osteoporosis, breast cancer, and lung cancer, etc. However, determining all the MVA pathway intermediates is still challenging due to their high polarity, low concentration, chelation effect with metal compartments, and poor mass spectrometric response. In this study, we established a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method coupled with N2, N2, N4, N4-tetramethyl-6-(4-(piperazin-1-ylsulfonyl) phenyl)-1,3,5-triazine-2,4-diamine (Tmt-PP) labeling for the simultaneous analysis of all MVA intermediates in biospecimens. Chemical derivatization significantly improved the chromatographic retention, peak shape, and detection sensitivity of the analytes. Moreover, we employed a method named mass spectrum calculation to achieve the absolute quantification of the isomers, i.e., isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP). The established method was fully qualified and applied to explore the difference of these metabolites in cisplatin-resistant non-small cell lung cancer (NSCLC) cells. Additionally, several MVA intermediate analogs, including isopentenyl monophosphate or dimethylallyl monophosphate (IMP/DMAMP), geranyl monophosphate (GMP), 5-triphosphomevalonate (MTP), and isopentenyl triphosphate or dimethylallyl triphosphate (ITP/DMATP), were identified for the first time using a knowledge-driven prediction strategy. We further explored the tissue distribution of these novel metabolites. Overall, this work developed a sensitive quantification method for all MVA intermediates, which will enhance our understanding of the role of this pathway in various health and disease conditions. The novel metabolites we discovered warrant further investigations into their biosynthesis and biological functions.
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Affiliation(s)
- Meiyu Gao
- Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), State Key Laboratory of Natural Medicine, China Pharmaceutical University, Nanjing 210009, PR China
| | - Jiarui Sun
- Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), State Key Laboratory of Natural Medicine, China Pharmaceutical University, Nanjing 210009, PR China
| | - Qinwen Xiao
- Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), State Key Laboratory of Natural Medicine, China Pharmaceutical University, Nanjing 210009, PR China
| | - Yuanyuan Zhai
- Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), State Key Laboratory of Natural Medicine, China Pharmaceutical University, Nanjing 210009, PR China
| | - Yuan Tian
- Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), State Key Laboratory of Natural Medicine, China Pharmaceutical University, Nanjing 210009, PR China
| | - Zunjian Zhang
- Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), State Key Laboratory of Natural Medicine, China Pharmaceutical University, Nanjing 210009, PR China
| | - Fengguo Xu
- Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), State Key Laboratory of Natural Medicine, China Pharmaceutical University, Nanjing 210009, PR China; School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 210009, PR China.
| | - Pei Zhang
- Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), State Key Laboratory of Natural Medicine, China Pharmaceutical University, Nanjing 210009, PR China.
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Guo Y, Bao K, Han D, Wu X, Li S, Dong Y, Zhang J. Study on in vitro NR biosynthesis by rapid quantitative determination of substrate depletion. J Biotechnol 2023; 361:80-88. [PMID: 36435303 DOI: 10.1016/j.jbiotec.2022.11.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 11/17/2022] [Accepted: 11/21/2022] [Indexed: 11/27/2022]
Abstract
A convenient and nonradioactive method for quantifying in vitro NR biosynthesis is presented that is based upon the quantitation of substrate depletion by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). NR oligomers could be in vitro biosynthesized with the enzyme source from Hevea brasiliensis (Hevea) or Taraxacum kok-saghyz (TKS) by exogenous monomers (IPP) and initiators (FPP). The IPP incorporation rate and FPP consumption rate were 62.24% and 51.14% respectively when the washed rubber particles (WRP) of Hevea was the enzyme source. The IPP incorporation rate and the FPP consumption rate were 74.49% and 95.90% respectively when the sediment bottom fraction (BF) of Hevea was the enzyme source. The in vitro NR biosynthesis can be divided into two stages:(1) the initiation reaction of FPP, which occurs more in BF, and (2) the growth reaction of IPP, which occurs more in WRP. In addition, the IPP incorporation and FPP consumption rates were 59.39% and 34.15% respectively when the BF of TKS was selected as an enzyme source.
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Affiliation(s)
- Yuwen Guo
- Center of Advanced Elastomer Materials, College of Material Science & Engineering, Beijing University of Chemical Technology, Beijing, 100029, PR China
| | - Kexu Bao
- Center of Advanced Elastomer Materials, College of Material Science & Engineering, Beijing University of Chemical Technology, Beijing, 100029, PR China
| | - Dongli Han
- Center of Advanced Elastomer Materials, College of Material Science & Engineering, Beijing University of Chemical Technology, Beijing, 100029, PR China; Energy Conservation and Resource Utilization Engineering Research Center of Elastomer Materials, Ministry of Education, Beijing University of Chemical Technology, Beijing, 100029, PR China
| | - Xiaohui Wu
- Center of Advanced Elastomer Materials, College of Material Science & Engineering, Beijing University of Chemical Technology, Beijing, 100029, PR China; Energy Conservation and Resource Utilization Engineering Research Center of Elastomer Materials, Ministry of Education, Beijing University of Chemical Technology, Beijing, 100029, PR China; Center of Advanced Elastomer Engineering Research, Beijing, Beijing University of Chemical Technology, 100029, PR China
| | - Shuangbing Li
- Zibo Nevc Advanced Vehicle Materials Technology Innovation Center, Shandong, 255000, PR China
| | - Yiyang Dong
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, PR China
| | - Jichuan Zhang
- Center of Advanced Elastomer Materials, College of Material Science & Engineering, Beijing University of Chemical Technology, Beijing, 100029, PR China; Energy Conservation and Resource Utilization Engineering Research Center of Elastomer Materials, Ministry of Education, Beijing University of Chemical Technology, Beijing, 100029, PR China; Center of Advanced Elastomer Engineering Research, Beijing, Beijing University of Chemical Technology, 100029, PR China.
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Fast Determination of the Rubber Content in Taraxacum kok-saghyz Fresh Biomass Using Portable Near-Infrared Spectroscopy and Pyrolysis–Gas Chromatography. JOURNAL OF ANALYSIS AND TESTING 2022. [DOI: 10.1007/s41664-022-00217-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Min Lao Y, Miao Lin Y, Sheng Wang X, Juan Xu X, Jin H. An improved method for sensitive quantification of isoprenoid diphosphates in the astaxanthin-accumulating Haematococcus pluvialis. Food Chem 2021; 375:131911. [PMID: 34959143 DOI: 10.1016/j.foodchem.2021.131911] [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: 07/10/2021] [Revised: 12/17/2021] [Accepted: 12/18/2021] [Indexed: 11/29/2022]
Abstract
A sensitive method has been established to simultaneously determine the concentrations of isopentenyl pyrophosphate (IPP), geranyl diphosphate (GPP), farnesyl diphosphate (FPP) and geranylgeranyl diphosphate (GGPP) in H. pluvialis under different environments. This method increased the extraction efficiency of isoprenoid diphosphates through releasing isoprenoid diphosphates using Tissue Lyser. This is the first report on the efficient extraction method of metabolites in H. pluvialis cells, being suitable for all algae and plants with thick cell wall. The concentrations of isoprenoid diphosphates were measured on poroshell EC-C18 column by UHPLC-MS/MS with the LODs of 0.015, 0.027, 0.022 and 0.076 pmol for DMAPP, GPP, FPP and GGPP, respectively. It is the most sensitive method for the determination of isoprenoid diphosphates in any sample to date. Using this method, the profile of isoprenoid diphosphates was analyzed and cisoid isomers of FPP and GGPP, (Z, Z)-FPP and (Z, Z, Z-GGPP) were found firstly in H. pluvialis.
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Affiliation(s)
- Yong Min Lao
- Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Yu Miao Lin
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Shenzhen 518107, China
| | - Xu Sheng Wang
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Shenzhen 518107, China
| | | | - Hui Jin
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Shenzhen 518107, China.
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Yuan B, Ding G, Ma J, Wang L, Yu L, Ruan X, Zhang X, Zhang W, Wang X, Xie Q. Comparison of Morphological Characteristics and Determination of Different Patterns for Rubber Particles in Dandelion and Different Rubber Grass Varieties. PLANTS 2020; 9:plants9111561. [PMID: 33202722 PMCID: PMC7696596 DOI: 10.3390/plants9111561] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 11/08/2020] [Accepted: 11/11/2020] [Indexed: 11/25/2022]
Abstract
Russian dandelion Taraxacum kok-saghyz (TKS) is one promising alternative crop for natural rubber production. However, it is easily confused with other dandelions. In this study, we performed a systematical comparison of the morphological characteristics for different TKS varieties and common dandelion Taraxacum officinale (TO). Our results demonstrated that several obvious differences in morphology can be found between TKS and TO. TO leaf is a pinnate shape, its margin is heavily jagged and its base is cuneate, but TKS leaf is more cuneate and its leaf margin is nearly smooth and round. There are obvious differences for the outer bracts of TO and TKS flower buds. TKS bracts are oblanceolate, apex obtuse, margin smooth and sinuate, and its outer layer of flower buds and faceplate involucre sepal is buckled inward to form a certain angle. TKS is self-incompatible, and its seeds are spindle-shaped achene and show upright plumpness. A large amount of laticifer cells and rubber particles can be detected from many TKS tissues, and dry roots of TKS contain high contents of natural rubber. Laticifer cells and rubber particles can only be examined in the vein, stem, and roots of TKS. Our statical results also revealed that the numbers of laticifer cells and rubber particles have a positive relationship with the rubber content in TKS roots. These morphological features can help us to easily distinguish TKS from common dandelion and approximately estimate the rubber content in the roots of different TKS varieties for TKS breeding in future.
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Affiliation(s)
- Boxuan Yuan
- Key Laboratory of Xinjiang Phytomedicine Resource and Utilization of Ministry of Education, College of Life Sciences, Shihezi University, Shihezi 832003, China; (B.Y.); (L.Y.)
- Key Laboratory for Ecology of Tropical Islands, Ministry of Education, College of Life Sciences, Hainan Normal University, Haikou 571158, China; (G.D.); (J.M.); (L.W.); (X.R.); (X.Z.)
| | - Guohua Ding
- Key Laboratory for Ecology of Tropical Islands, Ministry of Education, College of Life Sciences, Hainan Normal University, Haikou 571158, China; (G.D.); (J.M.); (L.W.); (X.R.); (X.Z.)
| | - Junjun Ma
- Key Laboratory for Ecology of Tropical Islands, Ministry of Education, College of Life Sciences, Hainan Normal University, Haikou 571158, China; (G.D.); (J.M.); (L.W.); (X.R.); (X.Z.)
| | - Lingling Wang
- Key Laboratory for Ecology of Tropical Islands, Ministry of Education, College of Life Sciences, Hainan Normal University, Haikou 571158, China; (G.D.); (J.M.); (L.W.); (X.R.); (X.Z.)
| | - Li Yu
- Key Laboratory of Xinjiang Phytomedicine Resource and Utilization of Ministry of Education, College of Life Sciences, Shihezi University, Shihezi 832003, China; (B.Y.); (L.Y.)
- Key Laboratory for Ecology of Tropical Islands, Ministry of Education, College of Life Sciences, Hainan Normal University, Haikou 571158, China; (G.D.); (J.M.); (L.W.); (X.R.); (X.Z.)
| | - Xueyu Ruan
- Key Laboratory for Ecology of Tropical Islands, Ministry of Education, College of Life Sciences, Hainan Normal University, Haikou 571158, China; (G.D.); (J.M.); (L.W.); (X.R.); (X.Z.)
| | - Xueyan Zhang
- Key Laboratory for Ecology of Tropical Islands, Ministry of Education, College of Life Sciences, Hainan Normal University, Haikou 571158, China; (G.D.); (J.M.); (L.W.); (X.R.); (X.Z.)
| | - Wangfeng Zhang
- The Key Laboratory of Oasis Eco-Agriculture, Agricultural College, Xinjiang Production and Construction Corps, Shihezi University, Shihezi 832003, China;
| | - Xuchu Wang
- Key Laboratory of Xinjiang Phytomedicine Resource and Utilization of Ministry of Education, College of Life Sciences, Shihezi University, Shihezi 832003, China; (B.Y.); (L.Y.)
- Key Laboratory for Ecology of Tropical Islands, Ministry of Education, College of Life Sciences, Hainan Normal University, Haikou 571158, China; (G.D.); (J.M.); (L.W.); (X.R.); (X.Z.)
- Correspondence: (X.W.); (Q.X.); Tel.: +86-898-65891065 (Q.X.)
| | - Quanliang Xie
- Key Laboratory of Xinjiang Phytomedicine Resource and Utilization of Ministry of Education, College of Life Sciences, Shihezi University, Shihezi 832003, China; (B.Y.); (L.Y.)
- Key Laboratory for Ecology of Tropical Islands, Ministry of Education, College of Life Sciences, Hainan Normal University, Haikou 571158, China; (G.D.); (J.M.); (L.W.); (X.R.); (X.Z.)
- The Key Laboratory of Oasis Eco-Agriculture, Agricultural College, Xinjiang Production and Construction Corps, Shihezi University, Shihezi 832003, China;
- Correspondence: (X.W.); (Q.X.); Tel.: +86-898-65891065 (Q.X.)
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Krause T, Reichelt M, Gershenzon J, Schmidt A. Analysis of the isoprenoid pathway intermediates, dimethylallyl diphosphate and isopentenyl diphosphate, from crude plant extracts by liquid chromatography tandem mass spectrometry. PHYTOCHEMICAL ANALYSIS : PCA 2020; 31:770-777. [PMID: 32337807 DOI: 10.1002/pca.2941] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/10/2020] [Accepted: 03/12/2020] [Indexed: 06/11/2023]
Abstract
OBJECTIVE We sought to develop a sensitive and accurate analytical method for the detection and quantification of IDP and DMADP as well as their monophosphate derivatives in crude plant extracts. METHODS A liquid chromatography method coupled to tandem mass spectrometry (LC-MS/MS) with multiple reaction monitoring (MRM) was established to measure the amounts of IDP and DMADP down to low picogram levels, which was linear over at least three orders of magnitude. Extracts were enriched using an anion exchanger, and chromatographic separation was achieved using a β-cyclodextrin column. A S-thiolodiphosphate analog of DMADP was employed as an internal standard. RESULTS Dilution series of authentic compounds were used to determine the limits of detection and quantification for IDP, DMADP and their corresponding monophosphates. A survey of plant species producing varying amounts of isoprenoids showed a corresponding variation in IDP and DMADP with the ratio of DMADP/IDP ranging from 4:1 to 2:1. Trace levels of isopentenyl monophosphate (IP) and dimethylallyl monophosphate (DMAP) were also detected. CONCLUSION The LC-MS/MS method described enables absolute quantification of in planta levels of IDP and DMADP for the first time. The method is also suitable for analysing bacterial and animal samples as well as enzyme assays.
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Affiliation(s)
- Toni Krause
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Michael Reichelt
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Jonathan Gershenzon
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Axel Schmidt
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
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Identification and Characterization of Glycoproteins and Their Responsive Patterns upon Ethylene Stimulation in the Rubber Latex. Int J Mol Sci 2020; 21:ijms21155282. [PMID: 32722428 PMCID: PMC7432319 DOI: 10.3390/ijms21155282] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 07/19/2020] [Accepted: 07/23/2020] [Indexed: 12/15/2022] Open
Abstract
Natural rubber is an important industrial material, which is obtained from the only commercially cultivated rubber tree, Hevea brasiliensis. In rubber latex production, ethylene has been extensively used as a stimulant. Recent research showed that post-translational modifications (PTMs) of latex proteins, such as phosphorylation, glycosylation and ubiquitination, are crucial in natural rubber biosynthesis. In this study, comparative proteomics was performed to identify the glycosylated proteins in rubber latex treated with ethylene for different days. Combined with Pro-Q Glycoprotein gel staining and mass spectrometry techniques, we provided the first visual profiling of glycoproteomics of rubber latex and finally identified 144 glycosylated protein species, including 65 differentially accumulated proteins (DAPs) after treating with ethylene for three and/or five days. Gene Ontology (GO) functional annotation showed that these ethylene-responsive glycoproteins are mainly involved in cell parts, membrane components and metabolism. Pathway analysis demonstrated that these glycosylated rubber latex proteins are mainly involved in carbohydrate metabolism, energy metabolism, degradation function and cellular processes in rubber latex metabolism. Protein-protein interaction analysis revealed that these DAPs are mainly centered on acetyl-CoA acetyltransferase and hydroxymethylglutaryl-CoA synthase (HMGS) in the mevalonate pathway for natural rubber biosynthesis. In our glycoproteomics, three protein isoforms of HMGS2 were identified from rubber latex, and only one HMGS2 isoform was sharply increased in rubber latex by ethylene treatment for five days. Furthermore, the HbHMGS2 gene was over-expressed in a model rubber-producing grass Taraxacum Kok-saghyz and rubber content in the roots of transgenic rubber grass was significantly increased over that in the wild type plant, indicating HMGS2 is the key component for natural rubber production.
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Aldana J, Romero-Otero A, Cala MP. Exploring the Lipidome: Current Lipid Extraction Techniques for Mass Spectrometry Analysis. Metabolites 2020; 10:metabo10060231. [PMID: 32503331 PMCID: PMC7345237 DOI: 10.3390/metabo10060231] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 05/05/2020] [Accepted: 05/13/2020] [Indexed: 12/14/2022] Open
Abstract
In recent years, high-throughput lipid profiling has contributed to understand the biological, physiological and pathological roles of lipids in living organisms. Across all kingdoms of life, important cell and systemic processes are mediated by lipids including compartmentalization, signaling and energy homeostasis. Despite important advances in liquid chromatography and mass spectrometry, sample extraction procedures remain a bottleneck in lipidomic studies, since the wide structural diversity of lipids imposes a constrain in the type and amount of lipids extracted. Differences in extraction yield across lipid classes can induce a bias on down-stream analysis and outcomes. This review aims to summarize current lipid extraction techniques used for untargeted and targeted studies based on mass spectrometry. Considerations, applications, and limitations of these techniques are discussed when used to extract lipids in complex biological matrices, such as tissues, biofluids, foods, and microorganisms.
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Wu C, Wang X, Zhang J, Cheng J, Shi L. Microencapsulation and Surface Functionalization of Ammonium Polyphosphate via In-Situ Polymerization and Thiol–Ene Photograted Reaction for Application in Flame-Retardant Natural Rubber. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b02464] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Optimization of extraction solvents, solid phase extraction and decoupling for quantitation of free isoprenoid diphosphates in Haematococcus pluvialis by liquid chromatography with tandem mass spectrometry. J Chromatogr A 2019; 1598:30-38. [PMID: 30929869 DOI: 10.1016/j.chroma.2019.03.051] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 03/14/2019] [Accepted: 03/22/2019] [Indexed: 01/19/2023]
Abstract
Isoprenoid diphosphates are important precursors actively participating in many downstream metabolisms; they are often in modified forms, e.g., protein-coupled or esterified form. Therefore, in vivo level of free isoprenoid diphosphates is quite low, ˜0.07 nmol/g fresh weight in plants. In order to directly measure the isoprenoid diphosphate pool during stress-induced accumulation of astaxanthin in Haematococcus pluvialis, the present study optimized several pretreatment procedures to enrich free isoprenoid diphosphates for high-pressure liquid chromatography with tandem mass spectrometry (HPLC-MS/MS) detection. Specifically, different extraction solvents, e.g., water, methanol, chloroform, and mixture of water, methanol, and chloroform (1:1:1, V/V/V), and solid phase extraction (SPE) columns (OASIS@ WAX and HLB Cartridges) were compared; and gentle decoupling by NaOH or trifluoroacetic acid (TFA) was introduced to release free isoprenoid diphosphates. Results found that solvent mixture of water, methanol and chloroform (1:1:1, V/V/V) showed the highest extraction efficiency (RE) for five isoprenoid diphosphates, ranging from 76.83% to 92.43%; HLB column showed the balanced recoveries ranging from 75.29% to 87.54%; and incubation with low NaOH (˜4.7 mmol/L) at 4 °C significantly increased detectable isoprenoid diphosphates in algal cells, some of which were undetectable or in trace level before NaOH decoupling. The method was applied to H. pluvialis cells under various stresses. Low levels of isoprenoid diphosphates were determined in most of the stresses used, e.g., 0.19 ± 0.09 to 0.98 ± 0.06 mg/g fresh weight (FW) for IPP/DMAPP, 0.35 ± 0.07 mg/g FW for GGPP and undetectable for FPP and GPP; while isoprenoid diphosphates were significantly accumulated in the dark to 3.27 ± 0.05, 0.17 ± 0.09, 1.81 ± 0.16 and 0.58 ± 0.07 mg/g FW for IPP/DMAPP, GPP, FPP and GGPP, respectively. These results implied that isoprenoid diphosphates were exhausted by downstream carotenogenesis under stress. Our work emphasizes NaOH decoupling for exact quantitation of in vivo isoprenoid diphosphates.
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