1
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Shields SWJ, Canez CR, Rosales CA, Roberts JA, Bourgaize H, Pallister PJ, Manthorpe JM, Smith JC. Optimized 13C-TrEnDi Enhances the Sensitivity of Plasmenyl Ether Glycerophospholipids and Demonstrates Compatibility with Other Derivatization Strategies. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:972-981. [PMID: 38551491 DOI: 10.1021/jasms.4c00015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
The identification and quantitation of plasmalogen glycerophospholipids is challenging due to their isobaric overlap with plasmanyl ether-linked glycerophospholipids, susceptibility to acid degradation, and their typically low abundance in biological samples. Trimethylation enhancement using diazomethane (TrEnDi) can be used to significantly enhance the signal of glycerophospholipids through the creation of quaternary ammonium groups producing fixed positive charges using 13C-diazomethane in complex lipid extracts. Although TrEnDi requires a strong acid for complete methylation, we report an optimized protocol using 10 mM HBF4 with the subsequent addition of a buffer solution that prevents acidic hydrolysis of plasmalogen species and enables the benefits of TrEnDi to be realized for this class of lipids. These optimized conditions were applied to aliquots of bovine liver extract (BLE) to achieve permethylation of plasmalogen lipids within a complex mixture. Treating aliquots of unmodified and TrEnDi-derivatized BLE samples with 80% formic acid and comparing their liquid chromatography mass spectrometry (LCMS) results to analogous samples not treated with formic acid, enabled the identification of 29 plasmalogen species. On average, methylated plasmalogen species from BLE demonstrated 2.81-fold and 28.1-fold sensitivity gains over unmodified counterparts for phosphatidylcholine and phosphatidylethanolamine plasmalogen species, respectively. Furthermore, the compatibility of employing 13C-TrEnDi and a previously reported iodoacetalization strategy was demonstrated to effectively identify plasmenyl-ether lipids in complex biological extracts at greater levels of sensitivity. Overall, we detail an optimized 13C-TrEnDi derivatization strategy that enables the analysis of plasmalogen glycerophospholipids with no undesired cleavage of radyl groups, boosting their sensitivity in LCMS and LCMS/MS analyses.
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Affiliation(s)
- Samuel W J Shields
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Carlos R Canez
- Institute of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Christian A Rosales
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Joshua A Roberts
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Hillary Bourgaize
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Peter J Pallister
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Jeffrey M Manthorpe
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Institute of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Jeffrey C Smith
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Institute of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
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2
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Gu TJ, Liu PK, Wang YW, Flowers MT, Xu S, Liu Y, Davis DB, Li L. Diazobutanone-assisted isobaric labelling of phospholipids and sulfated glycolipids enables multiplexed quantitative lipidomics using tandem mass spectrometry. Nat Chem 2024; 16:762-770. [PMID: 38365942 DOI: 10.1038/s41557-023-01436-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 12/21/2023] [Indexed: 02/18/2024]
Abstract
Mass spectrometry-based quantitative lipidomics is an emerging field aiming to uncover the intricate relationships between lipidomes and disease development. However, quantifying lipidomes comprehensively in a high-throughput manner remains challenging owing to the diverse lipid structures. Here we propose a diazobutanone-assisted isobaric labelling strategy as a rapid and robust platform for multiplexed quantitative lipidomics across a broad range of lipid classes, including various phospholipids and glycolipids. The diazobutanone reagent is designed to conjugate with phosphodiester or sulfate groups, while accommodating various functional groups on different lipid classes, enabling subsequent isobaric labelling for high-throughput multiplexed quantitation. Our method demonstrates excellent performance in terms of labelling efficiency, detection sensitivity, quantitative accuracy and broad applicability to various biological samples. Finally, we performed a six-plex quantification analysis of lipid extracts from lean and obese mouse livers. In total, we identified and quantified 246 phospholipids in a high-throughput manner, revealing lipidomic changes that may be associated with obesity in mice.
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Affiliation(s)
- Ting-Jia Gu
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI, USA
| | - Peng-Kai Liu
- Biophysics Graduate program, University of Wisconsin-Madison, Madison, WI, USA
| | - Yen-Wen Wang
- Department of Biostatics, Yale University, New Haven, CT, USA
| | - Matthew T Flowers
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA
| | - Shuling Xu
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI, USA
| | - Yuan Liu
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI, USA
| | - Dawn B Davis
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA
| | - Lingjun Li
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI, USA.
- Biophysics Graduate program, University of Wisconsin-Madison, Madison, WI, USA.
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.
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3
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Genva M, Fougère L, Bahammou D, Mongrand S, Boutté Y, Fouillen L. A global LC-MS 2 -based methodology to identify and quantify anionic phospholipids in plant samples. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 117:956-971. [PMID: 37937773 DOI: 10.1111/tpj.16525] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 10/10/2023] [Accepted: 10/21/2023] [Indexed: 11/09/2023]
Abstract
Anionic phospholipids (PS, PA, PI, PIPs) are low-abundant phospholipids with impactful functions in cell signaling, membrane trafficking and cell differentiation processes. They can be quickly metabolized and can transiently accumulate at defined spots within the cell or an organ to respond to physiological or environmental stimuli. As even a small change in their composition profile will produce a significant effect on biological processes, it is crucial to develop a sensitive and optimized analytical method to accurately detect and quantify them. While thin-layer chromatography (TLC) separation coupled with gas chromatography (GC) detection methods already exist, they do not allow for precise, sensitive, and accurate quantification of all anionic phospholipid species. Here we developed a method based on high-performance liquid chromatography (HPLC) combined with two-dimensional mass spectrometry (MS2 ) by MRM mode to detect and quantify all molecular species and classes of anionic phospholipids in one shot. This method is based on a derivatization step by methylation that greatly enhances the ionization, the separation of each peak, the peak resolution as well as the limit of detection and quantification for each individual molecular species, and more particularly for PA and PS. Our method universally works in various plant samples. Remarkably, we identified that PS is enriched with very long chain fatty acids in the roots but not in aerial organs of Arabidopsis thaliana. Our work thus paves the way for new studies on how the composition of anionic lipids is finely tuned during plant development and environmental responses.
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Affiliation(s)
- Manon Genva
- University of Bordeaux, CNRS, Laboratoire de Biogenèse Membranaire (LBM), UMR 5200, F-33140, Villenave d'Ornon, France
- Laboratory of Chemistry of Natural Molecules, Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés 2, 5030, Gembloux, Belgium
| | - Louise Fougère
- University of Bordeaux, CNRS, Laboratoire de Biogenèse Membranaire (LBM), UMR 5200, F-33140, Villenave d'Ornon, France
| | - Delphine Bahammou
- University of Bordeaux, CNRS, Laboratoire de Biogenèse Membranaire (LBM), UMR 5200, F-33140, Villenave d'Ornon, France
| | - Sébastien Mongrand
- University of Bordeaux, CNRS, Laboratoire de Biogenèse Membranaire (LBM), UMR 5200, F-33140, Villenave d'Ornon, France
| | - Yohann Boutté
- University of Bordeaux, CNRS, Laboratoire de Biogenèse Membranaire (LBM), UMR 5200, F-33140, Villenave d'Ornon, France
| | - Laetitia Fouillen
- University of Bordeaux, CNRS, Laboratoire de Biogenèse Membranaire (LBM), UMR 5200, F-33140, Villenave d'Ornon, France
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4
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Rosales CA, Sheedy KL, Wasslen KV, Manthorpe JM, Smith JC. Trimethylation Enhancement Using Diazomethane (TrEnDi) Enables Enhanced Detection of Glufosinate and 3-(Methylphosphinico)propionic Acid from Complex Canola Samples. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:140-150. [PMID: 38127770 DOI: 10.1021/jasms.3c00376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
Over the past century, agriculture practices have transitioned from manual cultivation to the use of an array of chemical herbicides for weed control including phosphinothricin, or glufosinate (GLUF). Consequently, the potential for long-term residual GLUF exposure in the food chain has increased, highlighting the need for improved analytical strategies for its detection, as well as the detection of its main breakdown product 3-(methylphosphinico)propionic acid (MPPA). Chemical derivatization strategies have been developed to improve the detection of GLUF and MPPA via liquid chromatography tandem mass spectrometry analyses. Herein, we employ trimethylation enhancement using diazomethane (TrEnDi) for the first time as a means to confer analytical advantages via quantitatively derivatizing these analytes into permethylated GLUF ([GLUFTr]+) and MPPA ([MPPATr+H]+). Comparing [GLUFTr]+ and [MPPATr+H]+ to underivatized counterparts, TrEnDi yields 2.8-fold and 1.7-fold improvements in reversed-phase chromatographic retention, respectively, while MS-based sensitivity is enhanced 4.1-fold and 11.0-fold, respectively. Successful analyte derivatization (with >99% yields) was further demonstrated on a commercial herbicide solution imparting consistent analytical enhancements. To investigate the benefits of TrEnDi in a bona fide agricultural scenario, simple aqueous extractions from distinct parts of field-grown canola plants were performed to quantify GLUF and MPPA before and after TrEnDi derivatization. In their underivatized forms, GLUF and MPPA were undetectable in all field samples, whereas [GLUFTr]+ and [MPPATr+H]+ were readily quantifiable using the same analysis conditions. Our results demonstrate that TrEnDi continues to be a useful tool to enhance the analytical characteristics of organic molecules that are traditionally difficult to detect.
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Affiliation(s)
- Christian A Rosales
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Krysten L Sheedy
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Karl V Wasslen
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Jeffrey M Manthorpe
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Institute of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Jeffrey C Smith
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Institute of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
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5
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Roberts JA, Rosales CA, Wasslen KV, Radnoff AS, Godbout E, Diallo JS, Manthorpe JM, Smith JC. An In Silico Database for Automated Feature Identification of High-Resolution Tandem Mass Spectrometry 13C-Trimethylation Enhancement Using Diazomethane ( 13C-TrEnDi)-Modified Lipid Data. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:2722-2730. [PMID: 37929927 DOI: 10.1021/jasms.3c00273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2023]
Abstract
13C-Trimethylation enhancement using diazomethane (13C-TrEnDi) is a chemical derivatization technique that uses 13C-labeled diazomethane to increase mass spectrometry (MS) signal intensities for phosphatidylcholine (PC) and phosphatidylethanolamine (PE) lipid classes, both of which are of major interest in biochemistry. In silico mass spectrometry databases have become mainstays in lipidomics experiments; however, 13C-TrEnDi-modified PC and PE species have altered m/z and fragmentation patterns from their native counterparts. To build a database of 13C-TrEnDi-modified PC and PE species, a lipid extract from nutritional yeast was derivatized and fragmentation spectra of modified PC and PE species were mined using diagnostic fragmentation filtering by searching 13C-TrEnDi-modified headgroups with m/z 199 (PC) and 202 (PE). Identities of 25 PC and 10 PE species were assigned after comparing to predicted masses from the Lipid Maps Structure Database with no false positive identifications observed; neutral lipids could still be annotated after derivatization. Collision energies from 16 to 52 eV were examined, resulting in three additional class-specific fragment ions emerging, as well as a combined sn-1/sn-2 fragment ion, allowing sum-composition level annotations to be assigned. Using the Lipid Blast templates, a NIST-compatible 13C-TrEnDi database was produced based on fragmentation spectra observed at 36 eV and tested on HEK 293T cell lipid extracts, identifying 47 PC and 24 PE species, representing a 1.8-fold and 2.2-fold increase in annotations, respectively. The 13C-TrEnDi database is freely available, MS vendor-independent, and widely compatible with MS data processing pipelines, increasing the throughput and accessibility of TrEnDi for lipidomics applications.
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Affiliation(s)
- Joshua A Roberts
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Christian A Rosales
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Karl V Wasslen
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Angela S Radnoff
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Elena Godbout
- Centre for Cancer Therapeutics, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada
| | - Jean-Simon Diallo
- Centre for Cancer Therapeutics, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada
| | - Jeffrey M Manthorpe
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Jeffrey C Smith
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
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6
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Ly R, Torres LC, Ly N, Britz-McKibbin P. Expanding Lipidomic Coverage in Multisegment Injection-Nonaqueous Capillary Electrophoresis-Mass Spectrometry via a Convenient and Quantitative Methylation Strategy. Anal Chem 2023; 95:17513-17524. [PMID: 37991882 DOI: 10.1021/acs.analchem.3c02605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2023]
Abstract
Orthogonal separation techniques coupled to high-resolution mass spectrometry are required for characterizing the human lipidome, given its inherent chemical and structural complexity. However, electrophoretic separations remain largely unrecognized in contemporary lipidomics research compared to established chromatographic and ion mobility methods. Herein, we introduce a novel derivatization protocol based on 3-methyl-1-p-tolyltriazene (MTT) as a safer alternative to diazomethane for quantitative phospholipid (PL) methylation (∼90%), which enables their rapid analysis by multisegment injection-nonaqueous capillary electrophoresis-mass spectrometry (MSI-NACE-MS). Isobaric interferences and ion suppression effects were minimized by performing an initial reaction using 9-fluorenylmethyoxycarbonyl chloride prior to MTT and a subsequent back extraction in hexane. This charge-switch derivatization strategy expands lipidome coverage when using MSI-NACE-MS under positive ion mode with improved resolution, greater sensitivity, and higher throughput (∼3.5 min/sample), notably for zwitterionic PLs that are analyzed as their cationic phosphate methyl esters. Our method was validated by analyzing methyl-tert-butyl ether extracts of reference human plasma, which enabled a direct comparison of 48 phosphatidylcholine and 27 sphingomyelin species previously reported in an interlaboratory lipidomics harmonization study. The potential for plasma PL quantification by MSI-NACE-MS via a serial dilution of NIST SRM-1950 was also demonstrated based on estimation of relative response factors using their reported consensus concentrations. Moreover, lipid identification was supported by modeling predictable changes in the electrophoretic mobility for cationic PLs in conjunction with MS/MS. Overall, this work offers a practical derivatization protocol to expand lipidome coverage in CE-MS beyond the analysis of hydrophilic/polar metabolites under aqueous buffer conditions.
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Affiliation(s)
- Ritchie Ly
- Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4M1
| | - Lucas Christian Torres
- Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4M1
| | - Nicholas Ly
- Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4M1
| | - Philip Britz-McKibbin
- Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4M1
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7
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Wang D, Xiao H, Lv X, Chen H, Wei F. Mass Spectrometry Based on Chemical Derivatization Has Brought Novel Discoveries to Lipidomics: A Comprehensive Review. Crit Rev Anal Chem 2023:1-32. [PMID: 37782560 DOI: 10.1080/10408347.2023.2261130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
Lipids, as one of the most important organic compounds in organisms, are important components of cells and participate in energy storage and signal transduction of living organisms. As a rapidly rising field, lipidomics research involves the identification and quantification of multiple classes of lipid molecules, as well as the structure, function, dynamics, and interactions of lipids in living organisms. Due to its inherent high selectivity and high sensitivity, mass spectrometry (MS) is the "gold standard" analysis technique for small molecules in biological samples. The combination chemical derivatization with MS detection is a unique strategy that could improve MS ionization efficiency, facilitate structure identification and quantitative analysis. Herein, this review discusses derivatization-based MS strategies for lipidomic analysis over the past decade and focuses on all the reported lipid categories, including fatty acids and modified fatty acids, glycerolipids, glycerophospholipids, sterols and saccharolipids. The functional groups of lipids mainly involved in chemical derivatization include the C=C group, carboxyl group, hydroxyl group, amino group, carbonyl group. Furthermore, representative applications of these derivatization-based lipid profiling methods were summarized. Finally, challenges and countermeasures of lipid derivatization are mentioned and highlighted to guide future studies of derivatization-based MS strategy in lipidomics.
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Affiliation(s)
- Dan Wang
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Oilseeds Processing of Ministry of Agriculture, Hubei Key Laboratory of Lipid Chemistry and Nutrition, Wuhan, Hubei, PR China
| | - Huaming Xiao
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Oilseeds Processing of Ministry of Agriculture, Hubei Key Laboratory of Lipid Chemistry and Nutrition, Wuhan, Hubei, PR China
| | - Xin Lv
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Oilseeds Processing of Ministry of Agriculture, Hubei Key Laboratory of Lipid Chemistry and Nutrition, Wuhan, Hubei, PR China
| | - Hong Chen
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Oilseeds Processing of Ministry of Agriculture, Hubei Key Laboratory of Lipid Chemistry and Nutrition, Wuhan, Hubei, PR China
| | - Fang Wei
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Oilseeds Processing of Ministry of Agriculture, Hubei Key Laboratory of Lipid Chemistry and Nutrition, Wuhan, Hubei, PR China
- Hubei Hongshan Laboratory, Wuhan, Hubei, PR China
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8
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Rosales CA, Shields SWJ, Aulenback CLJ, Elezi G, Wasslen KV, Pallister PJ, Faull KF, Manthorpe JM, Smith JC. Improved Chromatography and MS-Based Detection of Glyphosate and Aminomethylphosphonic Acid Using iTrEnDi. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:948-957. [PMID: 37132245 DOI: 10.1021/jasms.3c00026] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Glyphosate (GLY), a synthetic, nonselective systemic herbicide that is particularly effective against perennial weeds, is the most used weedkiller in the world. There are growing concerns over GLY accumulation in the environment and the attendant human health-associated risks, and despite increased attention in the media, GLY and its breakdown product aminomethylphosphonic acid (AMPA) remain elusive to many analytical strategies. Chemical derivatization coupled with high-performance liquid chromatography-mass spectrometry (HPLC-MS) addresses the challenge of quantifying low levels of GLY and AMPA in complex samples. Here we demonstrate the use of in situ trimethylation enhancement using diazomethane (iTrEnDi) to derivatize GLY and AMPA into permethylated products ([GLYTr]+ and [AMPATr]+, respectively) prior to analysis via HPLC-MS. iTrEnDi produced quantitative yields and resulted in a 12-340-fold increases in HPLC-MS-based sensitivity for [GLYTr]+ and [AMPATr]+, respectively, compared with underivatized counterparts. The limits of detection of derivatized compounds were found to be 0.99 ng/L for [GLYTr]+ and 1.30 ng/L for [AMPATr]+, demonstrating significant sensitivity improvements compared to previously established derivatization techniques. iTrEnDi is compatible with the direct derivatization of Roundup formulations. Finally, as proof of principle, a simple aqueous extraction followed by iTrEnDi enabled the detection of [GLYTr]+ and [AMPATr]+ on the exterior of field-grown soybeans that were sprayed with Roundup. Overall, iTrEnDi ameliorates issues relating to low proton affinity and chromatographic retention, boosting HPLC-MS-based sensitivity and enabling the elucidation of elusive analytes such as GLY and AMPA within agricultural systems.
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Affiliation(s)
- Christian A Rosales
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Samuel W J Shields
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Chelsey L J Aulenback
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Institute of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Gazmend Elezi
- Pasarow Mass Spectrometry Laboratory, Jane and Terry Semel Institute for Neuroscience and Human Behavior and the Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, California 90024, United States of America
| | - Karl V Wasslen
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Peter J Pallister
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Kym F Faull
- Pasarow Mass Spectrometry Laboratory, Jane and Terry Semel Institute for Neuroscience and Human Behavior and the Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, California 90024, United States of America
| | - Jeffrey M Manthorpe
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Institute of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Jeffrey C Smith
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Institute of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
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9
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Kim J, Seo S, Kim TY. Metabolic deuterium oxide (D 2O) labeling in quantitative omics studies: A tutorial review. Anal Chim Acta 2023; 1242:340722. [PMID: 36657897 DOI: 10.1016/j.aca.2022.340722] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 11/25/2022] [Accepted: 12/13/2022] [Indexed: 12/15/2022]
Abstract
Mass spectrometry (MS) is an invaluable tool for sensitive detection and characterization of individual biomolecules in omics studies. MS combined with stable isotope labeling enables the accurate and precise determination of quantitative changes occurring in biological samples. Metabolic isotope labeling, wherein isotopes are introduced into biomolecules through biosynthetic metabolism, is one of the main labeling strategies. Among the precursors employed in metabolic isotope labeling, deuterium oxide (D2O) is cost-effective and easy to implement in any biological systems. This tutorial review aims to explain the basic principle of D2O labeling and its applications in omics research. D2O labeling incorporates D into stable C-H bonds in various biomolecules, including nucleotides, proteins, lipids, and carbohydrates. Typically, D2O labeling is performed at low enrichment of 1%-10% D2O, which causes subtle changes in the isotopic distribution of a biomolecule, instead of the complete separation between labeled and unlabeled samples in a mass spectrum. D2O labeling has been employed in various omics studies to determine the metabolic flux, turnover rate, and relative quantification. Moreover, the advantages and challenges of D2O labeling and its future prospects in quantitative omics are discussed. The economy, versatility, and convenience of D2O labeling will be beneficial for the long-term omics studies for higher organisms.
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Affiliation(s)
- Jonghyun Kim
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology, Gwangju, 61005, South Korea
| | - Seungwoo Seo
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology, Gwangju, 61005, South Korea
| | - Tae-Young Kim
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology, Gwangju, 61005, South Korea.
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10
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Macias LA, Brodbelt JS. Enhanced Characterization of Cardiolipins via Hybrid 193 nm Ultraviolet Photodissociation Mass Spectrometry. Anal Chem 2022; 94:3268-3277. [PMID: 35135194 PMCID: PMC9284920 DOI: 10.1021/acs.analchem.1c05071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cardiolipins (CLs) constitute a structurally complex class of glycerophospholipids with a unique tetraacylated structure accompanied by distinctive functional roles. Aberrations in the composition of this lipid class have been associated with disease states, spurring interest in the development of new approaches to differentiate the structures of diverse CLs in complex mixtures. The structural characterization of these complex lipids using conventional methods, however, suffers from limited resolution and frequently proves unable to discern subtle yet biologically significant features such as unsaturation sites or acyl chain position assignments. Here, we describe the synergistic use of chemical derivatization and hybrid dissociation techniques to characterize CL from complex biological mixtures with both double bond and sn positional isomer resolution in a shotgun mass spectrometry strategy. Utilizing (trimethylsilyl)diazomethane (TMSD), CL phosphate groups were methylated to promote positive-mode ionization by the production of metal-cationized lipids, enabling structural interrogation via hybrid higher-energy collisional activation/ultraviolet photodissociation (HCD/UVPD). This combination of TMSD derivatization and HCD/UVPD fragmentation results in diagnostic product ions that permit distinction and relative quantitation of sn-stereoisomers and the localization of double bonds. Applying this strategy to a total lipid extract from a thyroid carcinoma revealed a previously unreported 18:2/18:1 motif, elucidating a structural feature unique to the lipid class.
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Affiliation(s)
- Luis A Macias
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Jennifer S Brodbelt
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
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11
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Bonney JR, Prentice BM. Perspective on Emerging Mass Spectrometry Technologies for Comprehensive Lipid Structural Elucidation. Anal Chem 2021; 93:6311-6322. [PMID: 33856206 PMCID: PMC8177724 DOI: 10.1021/acs.analchem.1c00061] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Lipids and metabolites are of interest in many clinical and research settings because it is the metabolome that is increasingly recognized as a more dynamic and sensitive molecular measure of phenotype. The enormous diversity of lipid structures and the importance of biological structure-function relationships in a wide variety of applications makes accurate identification a challenging yet crucial area of research in the lipid community. Indeed, subtle differences in the chemical structures of lipids can have important implications in cellular metabolism and many disease pathologies. The speed, sensitivity, and molecular specificity afforded by modern mass spectrometry has led to its widespread adoption in the field of lipidomics on many different instrument platforms and experimental workflows. However, unambiguous and complete structural identification of lipids by mass spectrometry remains challenging. Increasingly sophisticated tandem mass spectrometry (MS/MS) approaches are now being developed and seamlessly integrated into lipidomics workflows to meet this challenge. These approaches generally either (i) alter the type of ion that is interrogated or (ii) alter the dissociation method in order to improve the structural information obtained from the MS/MS experiment. In this Perspective, we highlight recent advances in both ion type alteration and ion dissociation methods for lipid identification by mass spectrometry. This discussion is aimed to engage investigators involved in fundamental ion chemistry and technology developments as well as practitioners of lipidomics and its many applications. The rapid rate of technology development in recent years has accelerated and strengthened the ties between these two research communities. We identify the common characteristics and practical figures of merit of these emerging approaches and discuss ways these may catalyze future directions of lipid structural elucidation research.
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Affiliation(s)
- Julia R Bonney
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Boone M Prentice
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
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12
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Shields SWJ, Rosales CA, Roberts JA, Pallister PJ, Wasslen KV, Manthorpe JM, Smith JC. iTrEnDi: In Situ Trimethylation Enhancement Using Diazomethane: Improved and Expanded Glycerophospholipid and Sphingolipid Analyses via a Microscale Autonomous Derivatization Platform. Anal Chem 2021; 93:1084-1091. [PMID: 33300778 DOI: 10.1021/acs.analchem.0c04088] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Trimethylation enhancement using diazomethane (TrEnDi) is a derivatization technique that significantly enhances the signal intensity of glycerophospholipid species in mass spectrometry (MS) and tandem mass spectrometry (MS/MS) analyses. Here, we describe a novel apparatus that is able to conduct in situ TrEnDi (iTrEnDi) by generating and immediately reacting small amounts of gaseous diazoalkane with analyte molecules. iTrEnDi allows complete and rapid methylation of phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidic acid (PA), and sphingomyelin (SM) in a safe manner by removing any need for direct handling of dangerous diazoalkane solutions. iTrEnDi-modified PC ([PCTr]+) and PE ([PETr]+) showed similar sensitivity enhancements and fragmentation patterns compared to our previously reported methodology. iTrEnDi yielded dimethylated PA ([PATr]), which exhibited dramatically improved chromatographic behavior and a 14-fold increase in liquid chromatography MS (LCMS) sensitivity compared to unmodified PA. In comparison to in-solution-based TrEnDi, iTrEnDi demonstrated a modest decrease in sensitivity, likely due to analyte losses during handling. However, the enhanced safety benefits of iTrEnDi coupled with its ease of use and capacity for automation, as well as its accommodation of more-reactive diazoalkane species, vastly improve the accessibility and utility of this derivatization technique. Finally, as a proof of concept, iTrEnDi was used to produce diazoethane (DZE), a more-reactive diazoalkane than diazomethane. Reaction between DZE and PC yielded ethylated [PCTr]+, which fragmented via MS/MS to produce a high-intensity characteristic fragment ion, enabling a novel and highly sensitive precursor ion scan.
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Affiliation(s)
- Samuel W J Shields
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada.,Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Christian A Rosales
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada.,Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Joshua A Roberts
- Institute of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada.,Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Peter J Pallister
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada.,Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Karl V Wasslen
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada.,Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Jeffrey M Manthorpe
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada.,Institute of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada.,Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Jeffrey C Smith
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada.,Institute of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada.,Carleton Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
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13
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Randolph CE, Blanksby SJ, McLuckey SA. Enhancing detection and characterization of lipids using charge manipulation in electrospray ionization-tandem mass spectrometry. Chem Phys Lipids 2020; 232:104970. [PMID: 32890498 PMCID: PMC7606777 DOI: 10.1016/j.chemphyslip.2020.104970] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/25/2020] [Accepted: 08/31/2020] [Indexed: 12/14/2022]
Abstract
Heightened awareness regarding the implication of disturbances in lipid metabolism with respect to prevalent human-related pathologies demands analytical techniques that provide unambiguous structural characterization and accurate quantitation of lipids in complex biological samples. The diversity in molecular structures of lipids along with their wide range of concentrations in biological matrices present formidable analytical challenges. Modern mass spectrometry (MS) offers an unprecedented level of analytical power in lipid analysis, as many advancements in the field of lipidomics have been facilitated through novel applications of and developments in electrospray ionization tandem mass spectrometry (ESI-MS/MS). ESI allows for the formation of intact lipid ions with little to no fragmentation and has become widely used in contemporary lipidomics experiments due to its sensitivity, reproducibility, and compatibility with condensed-phase modes of separation, such as liquid chromatography (LC). Owing to variations in lipid functional groups, ESI enables partial chemical separation of the lipidome, yet the preferred ion-type is not always formed, impacting lipid detection, characterization, and quantitation. Moreover, conventional ESI-MS/MS approaches often fail to expose diverse subtle structural features like the sites of unsaturation in fatty acyl constituents or acyl chain regiochemistry along the glycerol backbone, representing a significant challenge for ESI-MS/MS. To overcome these shortcomings, various charge manipulation strategies, including charge-switching, have been developed to transform ion-type and charge state, with aims of increasing sensitivity and selectivity of ESI-MS/MS approaches. Importantly, charge manipulation approaches afford enhanced ionization efficiency, improved mixture analysis performance, and access to informative fragmentation channels. Herein, we present a critical review of the current suite of solution-based and gas-phase strategies for the manipulation of lipid ion charge and type relevant to ESI-MS/MS.
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Affiliation(s)
- Caitlin E Randolph
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, USA
| | - Stephen J Blanksby
- Central Analytical Research Facility, Institute for Future Environments, Queensland University of Technology, Brisbane, QLD 4000, Australia
| | - Scott A McLuckey
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, USA.
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14
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Xia T, Ren H, Zhang W, Xia Y. Lipidome-wide characterization of phosphatidylinositols and phosphatidylglycerols on CC location level. Anal Chim Acta 2020; 1128:107-115. [PMID: 32825894 DOI: 10.1016/j.aca.2020.06.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 05/25/2020] [Accepted: 06/09/2020] [Indexed: 01/03/2023]
Abstract
Phosphatidylglycerol (PG) and phosphatidylinositol (PI) are two essential classes of glycerophospholipids (GPs), playing versatile roles such as signalling messengers and lipid-protein interaction ligands in cell. Although a majority of PG and PI molecular species contain unsaturated fatty acyl chain(s), conventional tandem mass spectrometry (MS/MS) methods cannot discern isomers different in carbon-carbon double bond (CC) locations. In this work, we paired phosphate methylation with acetone Paternò-Büchi (PB) reaction, aiming to provide a solution for sensitive and structurally informative analysis of these two important classes of GPs down to the location of CC. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) workflow was established. Offline methylated PG or PI mixtures were subjected to hydrophilic interaction chromatographic separation, online acetone PB reaction, and MS/MS via collision-induced dissociation (CID) for CC location determination in positive ion mode. This method was sensitive, offering limit of identification at 5 nM for both PG and PI standards down to CC locations. On molecular species level, 49 PI and 31 PG were identified from bovine liver, while 61 PIs were identified from human plasma. This workflow also enabled ratiometric comparisons of CC location isomers (C18:1 Δ9 vs. Δ11) of a series of PIs from type 2 diabetes (T2D) plasma to that of normal plasma samples. PI 16:0_18:1 and PI 18:0_18:1 were found to exhibit significant changes in CC isomeric ratios between T2D and normal plasma samples. The above results demonstrate that the developed LC-PB-MS/MS workflow is applicable to different classes of lipids and compatible with other established lipid derivatization methods to achieve comprehensive lipid analysis.
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Affiliation(s)
- Tian Xia
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Hanlin Ren
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Wenpeng Zhang
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, China; Department of Chemistry, Purdue University, West Lafayette, IN, 47907, USA
| | - Yu Xia
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, China.
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15
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Xu SL, Wu BF, Orešič M, Xie Y, Yao P, Wu ZY, Lv X, Chen H, Wei F. Double Derivatization Strategy for High-Sensitivity and High-Coverage Localization of Double Bonds in Free Fatty Acids by Mass Spectrometry. Anal Chem 2020; 92:6446-6455. [DOI: 10.1021/acs.analchem.9b05588] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Shu-ling Xu
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Oilseeds Processing of Ministry of Agriculture, Hubei Key Laboratory of Lipid Chemistry and Nutrition, Wuhan 430062, P. R. China
| | - Bang-fu Wu
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Oilseeds Processing of Ministry of Agriculture, Hubei Key Laboratory of Lipid Chemistry and Nutrition, Wuhan 430062, P. R. China
| | - Matej Orešič
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, FI-20520 Turku, Finland
- School of Medical Sciences, Örebro University, 702 81 Örebro, Sweden
| | - Ya Xie
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Oilseeds Processing of Ministry of Agriculture, Hubei Key Laboratory of Lipid Chemistry and Nutrition, Wuhan 430062, P. R. China
| | - Ping Yao
- Department of Nutrition and Food Hygiene, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, P. R. China
| | - Zong-yuan Wu
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Oilseeds Processing of Ministry of Agriculture, Hubei Key Laboratory of Lipid Chemistry and Nutrition, Wuhan 430062, P. R. China
| | - Xin Lv
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Oilseeds Processing of Ministry of Agriculture, Hubei Key Laboratory of Lipid Chemistry and Nutrition, Wuhan 430062, P. R. China
| | - Hong Chen
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Oilseeds Processing of Ministry of Agriculture, Hubei Key Laboratory of Lipid Chemistry and Nutrition, Wuhan 430062, P. R. China
| | - Fang Wei
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Oilseeds Processing of Ministry of Agriculture, Hubei Key Laboratory of Lipid Chemistry and Nutrition, Wuhan 430062, P. R. China
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16
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Franklin ET, Shields SWJ, Manthorpe JM, Smith JC, Xia Y, McLuckey SA. Coupling Headgroup and Alkene Specific Solution Modifications with Gas-Phase Ion/Ion Reactions for Sensitive Glycerophospholipid Identification and Characterization. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:938-945. [PMID: 32233382 PMCID: PMC7153167 DOI: 10.1021/jasms.0c00001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Shotgun lipidomics provides sensitive and fast lipid identification without the need for chromatographic separation. Challenges faced by shotgun analysis of glycerophospholipids (GPs) include the lack of signal uniformity across GP classes and the inability to determine the carbon-carbon double bond (C═C) location within the fatty acyl chains of an unsaturated species. Two distinct derivatization strategies were employed to both enhance the ionization of GPs, via trimethylation enhancement using 13C-diazomethane (13C-TrEnDi), as well as determine location of double bonds within fatty acyl chains, employing an in-solution photochemical reaction with acetone (via the Paternò-Büchi reaction). The modified GPs were then subjected to positive ion mode ionization via electrospray ionization, producing uniform ionization efficiencies for different classes of GP species. The GPs were charge inverted via gas-phase ion/ion reactions and sequentially fragmented using ion trap collision-induced dissociation (CID). The CID of the species led to fragmentation producing diagnostic ions indicative of C═C bond location. The approach enabled enhanced ionization and the identification of phosphatidylcholine and phosphatidylethanolamine species at the C═C level in a bovine lipid extract.
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Affiliation(s)
- Elissia T. Franklin
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, United States, 47907-2084, West Lafayette, IN, United States 47907-2084
| | - Samuel W. J. Shields
- Department of Chemistry and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada
| | - Jeffrey M. Manthorpe
- Department of Chemistry and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada
| | - Jeffrey C. Smith
- Department of Chemistry and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada
| | - Yu Xia
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, United States, 47907-2084, West Lafayette, IN, United States 47907-2084
- Department of Chemistry, Tsinghua University, Mengminwei Technical Building, Beijing, Haidian, China, 100084
| | - Scott A. McLuckey
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, United States, 47907-2084, West Lafayette, IN, United States 47907-2084
- Address reprint requests to Scott A. McLuckley, 560 Oval Drive, West Lafayette, IN, United States, 47907-2084, West Lafayette, IN, United States 47907-2084,
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17
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Pagliano E. Versatile derivatization for GC-MS and LC-MS: alkylation with trialkyloxonium tetrafluoroborates for inorganic anions, chemical warfare agent degradation products, organic acids, and proteomic analysis. Anal Bioanal Chem 2020; 412:1963-1971. [PMID: 31915869 DOI: 10.1007/s00216-019-02299-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 11/04/2019] [Accepted: 11/21/2019] [Indexed: 10/25/2022]
Abstract
Analytical chemists resort to derivatization for improving the detection performance of certain categories of analytes. Within this context, alkylation reactions are regarded as an important asset for many methods based on GC-MS and LC-MS. Trialkyloxonium tetrafluoroborates (R[Formula: see text][BF4]-) are powerful alkylating agents with ionic liquid properties: they are nonvolatile salts soluble in water which are easier and safer to handle with respect to common alkylating agents like diazomethane. R[Formula: see text][BF4]- can perform the alkylation in both organic and aqueous media at pH conditions ranging from acidic to alkaline. Recent analytical applications of trialkyloxonium derivatizations include the high-precision determination of inorganic anions in complex matrices, the qualitative confirmation of chemical warfare agent degradation products in soils, the profiling of carboxylic acids in urine, and the detection of protein post-translational modifications induced by carbon dioxide. The common denominator for all methods presented can be found in the simplicity of the alkylation protocol which, in most of the cases, requires a single step addition of the reagent directly to the sample. Graphical Abstract Alkylation with trialkyloxonium salts for GC-MS and LC-MS analysis.
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Affiliation(s)
- Enea Pagliano
- National Research Council Canada, 1200 Montreal Road, K1A 0R6, Ottawa, Ontario, Canada.
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18
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Wei F, Lamichhane S, Orešič M, Hyötyläinen T. Lipidomes in health and disease: Analytical strategies and considerations. Trends Analyt Chem 2019. [DOI: 10.1016/j.trac.2019.115664] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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19
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Wang S, Sun S, Shan C, Pan B. Analysis of trace phosphonates in authentic water samples by pre-methylation and LC-Orbitrap MS/MS. WATER RESEARCH 2019; 161:78-88. [PMID: 31181449 DOI: 10.1016/j.watres.2019.05.099] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 05/28/2019] [Accepted: 05/29/2019] [Indexed: 06/09/2023]
Abstract
Phosphonate is an important phosphorous species in the effluent of wastewater treatment plant (WWTP), contributing to eutrophication and interfering with phosphate removal in WWTP. It is particularly difficult to determine phosphonates in samples of complex solution chemistry, resulting in very limited information on their presence in environmental matrices. Herein, we proposed a sensitive method based on liquid chromatography tandem mass spectrometry (LC-MS/MS) to determine six quantitatively most important phosphonates even at the ng/L level, i.e., 2-phosphonobutane-1,2,4-tricarboxylic acid, 1-hydroxyethane 1,1-diphosphonic acid, nitrilotris(methylene phosphonic acid), ethylenediamine tetra(methylene phosphonic acid), hexamethylenediamine tetra(methylene phosphonic acid) and diethylenetriamine penta(methylene phosphonic acid). Trimethylsilyldiazomethane (TMSCHN2) derivatization of the target phosphonates is pre-requisite since it could greatly increase the sensitivity up to 2-3 orders of magnitude over direct analysis of the virgin ones. The sample pretreatment methods (including ion exchange and solid phase extraction(SPE)), the derivatization procedures, and the LC-MS/MS conditions were systematically optimized. The limits of quantitation for the six phosphonates in the background of tap water ranged from 1.4 μg/L to 57 μg/L for direct analysis, and from 5.0 ng/L to 200 ng/L for SPE enabled pre-concentration analysis, respectively. The reliability of the proposed method was successfully validated by analysis of authentic water samples collected from one river and three WWTPs (0.088-7200 μg/L phosphonates) with satisfactory recoveries (72-126%). To the best of knowledge, this is the first report on quantification of phosphonates in environmental samples in China.
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Affiliation(s)
- Shu Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, 210023, China
| | - Shuhui Sun
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, 210023, China
| | - Chao Shan
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, 210023, China
| | - Bingcai Pan
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, 210023, China.
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20
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Zheng X, Zeng J, Xiong M, Huang J, Li C, Zhou R, Xiao D. Methyl Trifluoroacetate as a Methylation Reagent for N−H, O−H, and S−H Functionalities under Mild Conditions. ASIAN J ORG CHEM 2019. [DOI: 10.1002/ajoc.201900413] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Xin Zheng
- College of ChemistryGuangdong University of Petrochemical Technology Maoming 525000 P. R. China
| | - Jiechun Zeng
- College of ChemistryGuangdong University of Petrochemical Technology Maoming 525000 P. R. China
| | - Mindong Xiong
- College of ChemistryGuangdong University of Petrochemical Technology Maoming 525000 P. R. China
| | - Jiawei Huang
- College of ChemistryGuangdong University of Petrochemical Technology Maoming 525000 P. R. China
| | - Cuiyan Li
- College of ChemistryGuangdong University of Petrochemical Technology Maoming 525000 P. R. China
| | - Rujin Zhou
- College of ChemistryGuangdong University of Petrochemical Technology Maoming 525000 P. R. China
| | - Duoduo Xiao
- College of ChemistryGuangdong University of Petrochemical Technology Maoming 525000 P. R. China
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21
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Kim J, Kang D, Lee SK, Kim TY. Deuterium Oxide Labeling for Global Omics Relative Quantification: Application to Lipidomics. Anal Chem 2019; 91:8853-8863. [PMID: 31246424 DOI: 10.1021/acs.analchem.9b00086] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A novel quantitative mass spectrometric method based on partial metabolic deuterium oxide (D2O) labeling, named "Deuterium Oxide Labeling for Global Omics Relative Quantification (DOLGOReQ)", was developed for relative quantification of lipids on a global scale. To assess the precision and robustness of DOLGOReQ, labeled and unlabeled lipids from HeLa cells were mixed in various ratios based on their cell numbers. Using in-house software developed for automated high-throughput data analysis of DOLGOReQ, the number of detectable mass isotopomers and the degree of deuterium labeling were exploited to filter out low quality quantification results. Quantification of an equimolar mixture of HeLa cell lipids exhibited high reproducibility and accuracy across multiple biological and technical replicates. Two orders of magnitude of effective dynamic range for reasonable relative quantification could be established with HeLa cells mixed from 10:1 to 1:10 ratios between labeled and unlabeled samples. The quantification precision of DOLGOReQ was also illustrated with lipids commonly detected in both positive and negative ion modes. Finally, quantification performance of DOLGOReQ was demonstrated in a biological sample by measuring the relative change in the lipidome of HeLa cells under normal and hypoxia conditions.
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Affiliation(s)
- Jonghyun Kim
- School of Earth Sciences and Environmental Engineering , Gwangju Institute of Science and Technology , Gwangju 61005 , Republic of Korea
| | - Dukjin Kang
- Center for Bioanalysis, Division of Chemical and Medical Metrology , Korea Research Institute of Standards and Science , Daejeon 34113 , Republic of Korea
| | - Sung Ki Lee
- Department of Obstetrics and Gynecology , College of Medicine, Konyang University , Daejeon 35365 , Republic of Korea
| | - Tae-Young Kim
- School of Earth Sciences and Environmental Engineering , Gwangju Institute of Science and Technology , Gwangju 61005 , Republic of Korea
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22
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Franklin ET, Betancourt SK, Randolph CE, McLuckey SA, Xia Y. In-depth structural characterization of phospholipids by pairing solution photochemical reaction with charge inversion ion/ion chemistry. Anal Bioanal Chem 2019; 411:4739-4749. [PMID: 30613841 DOI: 10.1007/s00216-018-1537-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 11/25/2018] [Accepted: 12/03/2018] [Indexed: 11/25/2022]
Abstract
Shotgun lipid analysis based on electrospray ionization-tandem mass spectrometry (ESI-MS/MS) is increasingly used in lipidomic studies. One challenge for the shotgun approach is the discrimination of lipid isomers and isobars. Gas-phase charge inversion via ion/ion reactions has been used as an effective method to identify multiple isomeric/isobaric components in a single MS peak by exploiting the distinctive functionality of different lipid classes. In doing so, fatty acyl chain information can be obtained without recourse to condensed-phase separations or derivatization. This method alone, however, cannot provide carbon-carbon double bond (C=C) location information from fatty acyl chains. Herein, we provide an enhanced method pairing photochemical derivatization of C=C via the Paternò-Büchi reaction with charge inversion ion/ion tandem mass spectrometry. This method was able to provide gas-phase separation of phosphatidylcholines and phosphatidylethanolamines, the fatty acyl compositions, and the C=C location within each fatty acyl chain. We have successfully applied this method to bovine liver lipid extracts and identified 40 molecular species of glycerophospholipids with detailed structural information including head group, fatty acyl composition, and C=C location. Graphical Abstract ᅟ.
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Affiliation(s)
- Elissia T Franklin
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47907-2084, USA
| | - Stella K Betancourt
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47907-2084, USA
| | - Caitlin E Randolph
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47907-2084, USA
| | - Scott A McLuckey
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47907-2084, USA.
| | - Yu Xia
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47907-2084, USA.
- Department of Chemistry, Tsinghua University, Beijing, 100084, China.
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23
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Huang T, Armbruster MR, Coulton JB, Edwards JL. Chemical Tagging in Mass Spectrometry for Systems Biology. Anal Chem 2018; 91:109-125. [DOI: 10.1021/acs.analchem.8b04951] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Tianjiao Huang
- Department of Chemistry, Saint Louis University, 3501 Laclede Avenue, St. Louis, Missouri 63103, United States
| | - Michael R. Armbruster
- Department of Chemistry, Saint Louis University, 3501 Laclede Avenue, St. Louis, Missouri 63103, United States
| | - John B. Coulton
- Department of Chemistry, Saint Louis University, 3501 Laclede Avenue, St. Louis, Missouri 63103, United States
| | - James L. Edwards
- Department of Chemistry, Saint Louis University, 3501 Laclede Avenue, St. Louis, Missouri 63103, United States
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24
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Vuckovic D. Improving metabolome coverage and data quality: advancing metabolomics and lipidomics for biomarker discovery. Chem Commun (Camb) 2018; 54:6728-6749. [PMID: 29888773 DOI: 10.1039/c8cc02592d] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This Feature Article highlights some of the key challenges within the field of metabolomics and examines what role separation and analytical sciences can play to improve the use of metabolomics in biomarker discovery and personalized medicine. Recent progress in four key areas is highlighted: (i) improving metabolite coverage, (ii) developing accurate methods for unstable metabolites including in vivo global metabolomics methods, (iii) advancing inter-laboratory studies and reference materials and (iv) improving data quality, standardization and quality control of metabolomics studies.
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Affiliation(s)
- Dajana Vuckovic
- Department of Chemistry and Biochemistry, Concordia University, 7141 Sherbrooke Street West, Montréal, Québec H4B 1R6, Canada.
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25
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Rapid profiling and quantification of phospholipid molecular species in human plasma based on chemical derivatization coupled with electrospray ionization tandem mass spectrometry. Anal Chim Acta 2018; 1024:101-111. [PMID: 29776536 DOI: 10.1016/j.aca.2018.04.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 04/13/2018] [Accepted: 04/13/2018] [Indexed: 12/23/2022]
Abstract
In this study, we developed a novel strategy using solid-phase extraction (SPE) coupled with shotgun mass spectrometry (MS) based on trimethylsilyldiazomethane (TMSCHN2) stable-isotope derivatization for rapid profiling and accurate quantification of phospholipids (PLs) in human plasma. HybridSPE-Phospholipid (HybridSPE-PL, zirconia coated silica stationary phase) was used for sample pretreatment via the Lewis acid-base interaction between zirconia and phosphate moiety of PLs. This step allows rapid enrichment and recovery of PLs from human plasma. Afterward, PLs were derivatized with TMSCHN2, which leads to methylation of hydroxyl and amino groups in PLs and allows highly sensitive PL analysis by shotgun MS in positive ionization mode (limit of detection decreased up to 116.67 fold compared to underived PLs). We developed an accuracy quantification method for determination of PL molecular species in biological samples. Two or more PL standards were selected for each PL class and derivatized with TMSCHN2 without stable-isotope coding. They were then used as the internal standards. PLs in biological samples were isotopic derivatized via acid-catalyzed H/D exchange and methanolysis of TMSCHN2. For accurate quantification, a calibration curve for each class of PLs was typically constructed by using the internal standards to normalize the non-uniformity response caused by the differential fragmentation kinetics resulting from the distinct chemical constitution of individual PL species in the biological samples. This newly developed method was used to comprehensively analyze PL molecular species in human plasma samples. It is a promising methodology for rapid profiling and accurate quantification of complex lipid molecules in biological samples.
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26
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Cai T, Yang F. Phospholipid and Phospholipidomics in Health and Diseases. LIPIDOMICS IN HEALTH & DISEASE 2018. [DOI: 10.1007/978-981-13-0620-4_11] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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27
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Betancourt SK, Canez CR, Shields SWJ, Manthorpe JM, Smith JC, McLuckey SA. Trimethylation Enhancement Using 13C-Diazomethane: Gas-Phase Charge Inversion of Modified Phospholipid Cations for Enhanced Structural Characterization. Anal Chem 2017; 89:9452-9458. [PMID: 28764333 DOI: 10.1021/acs.analchem.7b02271] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Methylation of phospholipids (PL) leads to increased uniformity in positive electrospray ionization (ESI) efficiencies across the various PL subclasses. This effect is realized in the approach referred to as "trimethylation enhancement using 13C-diazomethane" (13C-TrEnDi), which results in the methyl esterification of all acidic sites and the conversion of amines to quaternary ammonium sites. Collision-induced dissociation (CID) of these cationic modified lipids enables class identification by forming distinctive headgroup fragments based on the number of 13C atoms incorporated during derivatization. However, there are no distinctive fragment ions in positive mode that provide fatty acyl information for any of the modified lipids. Gas-phase ion/ion reactions of 13C-TrEnDi-modified phosphatidylethanolamine (PE), phosphatidylserine (PS), phosphatidylcholine (PC), and sphingomyelin (SM) cations with dicarboxylate anions are shown to charge-invert the positively charged phospholipids to the negative mode. An electrostatically bound complex anion is shown to fragment predominantly via a novel headgroup dication transfer to the reagent anion. Fragmentation of the resulting anionic product yields fatty acyl information, in the case of the glycerophospholipids (PE, PS, and PC), via ester bond cleavage. Analogous information is obtained from modified SM lipid anions via amide bond cleavage. Fragmentation of the anions generated from charge inversion of the 13C-TrEnDi-modified phospholipids was also found to yield lipid class information without having to perform CID in positive mode. The combination of 13C-TrEnDi modification of lipid mixtures with charge inversion to the negative-ion mode retains the advantages of uniform ionization efficiency in the positive-ion mode with the additional structural information available in the negative-ion mode without requiring the lipids to be ionized directly in both ionization modes.
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Affiliation(s)
- Stella K Betancourt
- Department of Chemistry, Purdue University , West Lafayette, Indiana 47907-2084, United States
| | - Carlos R Canez
- Department of Chemistry and Institute of Biochemistry, Carleton University , Ottawa, Ontario K1S 5B6, Canada
| | - Samuel W J Shields
- Department of Chemistry and Institute of Biochemistry, Carleton University , Ottawa, Ontario K1S 5B6, Canada
| | - Jeffrey M Manthorpe
- Department of Chemistry and Institute of Biochemistry, Carleton University , Ottawa, Ontario K1S 5B6, Canada
| | - Jeffrey C Smith
- Department of Chemistry and Institute of Biochemistry, Carleton University , Ottawa, Ontario K1S 5B6, Canada
| | - Scott A McLuckey
- Department of Chemistry, Purdue University , West Lafayette, Indiana 47907-2084, United States
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28
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Lee JC, Byeon SK, Moon MH. Relative Quantification of Phospholipids Based on Isotope-Labeled Methylation by Nanoflow Ultrahigh Performance Liquid Chromatography-Tandem Mass Spectrometry: Enhancement in Cardiolipin Profiling. Anal Chem 2017; 89:4969-4977. [PMID: 28399627 DOI: 10.1021/acs.analchem.7b00297] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In this study, lipid analysis based on isotope-labeled methlylation (ILM) was performed by nanoflow ultrahigh performance liquid chromatography-eletrospray ionization-tandem mass spectrometry (nUPLC-ESI-MS/MS) for enhanced detection and quantification of targeted phospholipids. ILM depends on methylation of phosphate groups by (trimethylsilyl)diazomethane, and the ILM based quantitation with reversed phase nUPLC-ESI-MS/MS provides advantages in PL profiling such as enhanced detectability of methylated PLs owing to increased hydrophobicity and substantial increase in resolution due to the increase of retention. Efficacy of ILM in nUPLC-ESI-MS/MS analysis was evaluated in the selected reaction monitoring (SRM) method by varying the mixing ratio of H-/D-methylated PL standards, which resulted in the successful quantification of 24 species, including phosphatidic acid (PA), phosphatidylserine (PS), phosphatidylglycerol (PG), ceramide-1-phosphate (Cer1P), phosphoinositides, and cardiolipin (CL), with ∼6.6% variation in the calculated ratio of H-/D-methylated PLs. The method was applied to the lipid extracts from a DU145 cell line after D-allose treatment, resulting in the quantification of 83 PLs of which results were not statistically different from those obtained by conventional quantification methods. Morever, detection and quantification of CLs and PAs were evidenced to be highly effective when used with the ILM method as 43 CLs and 20 PAs from cellular lipid extracts were analyzed while only 18 CLs and 12 PAs were identified when conventional methods were carried out. This proves the ILM combined with LC-MS to be a promising method for analysis of the aforementioned classes of lipids. Overall, the study highlighted the applicability of targeted quantification by the ILM method in lipidomic analysis and demonstrated an improvement in the detection of less abundant anionic PLs.
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Affiliation(s)
- Jong Cheol Lee
- Department of Chemistry, Yonsei University , 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea
| | - Seul Kee Byeon
- Department of Chemistry, Yonsei University , 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea
| | - Myeong Hee Moon
- Department of Chemistry, Yonsei University , 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea
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29
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Klein DR, Brodbelt JS. Structural Characterization of Phosphatidylcholines Using 193 nm Ultraviolet Photodissociation Mass Spectrometry. Anal Chem 2017; 89:1516-1522. [PMID: 28105803 PMCID: PMC5480246 DOI: 10.1021/acs.analchem.6b03353] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Advances in mass spectrometry have made it a preferred tool for structural characterization of glycerophospholipids. Collisional activation methods commonly implemented on commercial instruments do not provide fragmentation patterns that allow elucidation of certain structural features, including acyl chain positions on the glycerol backbone and double bond positions within acyl chains. In the present work, 193 nm ultraviolet photodissociation (UVPD) implemented on an Orbitrap mass spectrometer is used to localize double bond positions within phosphatidylcholine (PC) acyl chains. Cleavage of the carbon-carbon bonds adjacent to the double bond provides a diagnostic mass difference of 24 Da and enables differentiation of double-bond positional isomers. The UVPD method was extended to the characterization of PCs in a bovine liver extract via a shotgun strategy. Positive mode higher energy collisional dissociation (HCD) and UVPD, and negative mode HCD were undertaken in a complementary manner to identify species as PCs and to localize double bonds, respectively.
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Affiliation(s)
- Dustin R Klein
- Department of Chemistry, The University of Texas at Austin , Austin, Texas 78712, United States
| | - Jennifer S Brodbelt
- Department of Chemistry, The University of Texas at Austin , Austin, Texas 78712, United States
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30
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Jurowski K, Kochan K, Walczak J, Barańska M, Piekoszewski W, Buszewski B. Comprehensive review of trends and analytical strategies applied for biological samples preparation and storage in modern medical lipidomics: State of the art. Trends Analyt Chem 2017. [DOI: 10.1016/j.trac.2016.10.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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31
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Kim SH, Song HE, Kim SJ, Woo DC, Chang S, Choi WG, Kim MJ, Back SH, Yoo HJ. Quantitative structural characterization of phosphatidylinositol phosphates from biological samples. J Lipid Res 2016; 58:469-478. [PMID: 27940482 DOI: 10.1194/jlr.d069989] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Revised: 12/06/2016] [Indexed: 12/31/2022] Open
Abstract
The aspects of cellular metabolism controlled by phosphatidylinositol phosphates (PtdInsPs) have been broadly expanded, and these phospholipids have drawn tremendous attention as pleiotropic signaling molecules. PtdInsPs analysis using LC/MS/MS has remained challenging due to the strong hydrophilicity of these lipids. Multiple reaction monitoring (MRM) or a neutral loss scan has been performed to quantitatively measure PtdInsPs after chemical derivatization on the phosphate groups of inositol moieties. Only predefined PtdInsPs can be measured in MRM mode, and fatty acyl compositions of sn-1 and sn-2 positions of PtdInsPs cannot be obtained from a neutral loss scan. In our present study, we developed a simple LC/MS/MS method for structural identification of sn-1 and sn-2 fatty acids of PtdInsPs and their relative quantitation. Precursor ion scans of sn-1 monoacylglycerols (MAGs) of PtdInsPs provided structural information about the lipids, and ammonium adduction enhanced signal intensities of PtdInsPs. The relative amount of observed PtdInsPs in biological samples could be compared using chromatographic peak areas from the neutral loss scans. Using precursor ion scans of sn-1 MAG and neutral loss scans of headgroups, major PtdInsPs in cells and tissues were successfully identified with structural information of sn-1 and sn-2 fatty acids, and their relative amounts in different samples were compared.
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Affiliation(s)
- Su Hee Kim
- Biomedical Research Center, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | - Ha Eun Song
- Biomedical Research Center, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | - Su Jung Kim
- Biomedical Research Center, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | - Dong Cheol Woo
- Biomedical Research Center, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea.,Department of Convergence Medicine, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | - Suhwan Chang
- Division of Biomedical Sciences, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | - Woo Gyun Choi
- School of Biological Sciences, University of Ulsan, Ulsan 44610, Republic of Korea
| | - Mi Jeong Kim
- School of Biological Sciences, University of Ulsan, Ulsan 44610, Republic of Korea
| | - Sung Hoon Back
- School of Biological Sciences, University of Ulsan, Ulsan 44610, Republic of Korea
| | - Hyun Ju Yoo
- Biomedical Research Center, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea .,Department of Convergence Medicine, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
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32
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Ryan E, Reid GE. Chemical Derivatization and Ultrahigh Resolution and Accurate Mass Spectrometry Strategies for "Shotgun" Lipidome Analysis. Acc Chem Res 2016; 49:1596-604. [PMID: 27575732 DOI: 10.1021/acs.accounts.6b00030] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Lipids play critical structural and functional roles in the regulation of cellular homeostasis, and it is increasingly recognized that the disruption of lipid metabolism or signaling or both is associated with the onset and progression of certain metabolically linked diseases. As a result, the field of lipidomics has emerged to comprehensively identify and structurally characterize the diverse range of lipid species within a sample of interest and to quantitatively monitor their abundances under different physiological or pathological conditions. Mass spectrometry (MS) has become a critical enabling platform technology for lipidomic researchers. However, the presence of isobaric (i.e., same nominal mass) and isomeric (i.e., same exact mass) lipids within complex lipid extracts means that MS-based identification and quantification of individual lipid species remains a significant analytical challenge. Ultrahigh resolution and accurate mass spectrometry (UHRAMS) offers a convenient solution to the isobaric mass overlap problem, while a range of chromatographic separation, differential extraction, intrasource separation and selective ionization methods, or tandem mass spectrometry (MS/MS) strategies may be used to address some types of isomeric mass lipid overlaps. Alternatively, chemical derivatization strategies represent a more recent approach for the separation of lipids within complex mixtures, including for isomeric lipids. In this Account, we highlight the key components of a lipidomics workflow developed in our laboratory, whereby certain lipid classes or subclasses, namely, aminophospholipids and O-alk-1'-enyl (i.e., plasmalogen) ether-containing lipids, are shifted in mass following sequential functional group selective chemical derivatization reactions prior to "shotgun" nano-ESI-UHRAMS analysis, "targeted" MS/MS, and automated database searching. This combined derivatization and UHRAMS approach resolves both isobaric mass lipids and certain categories of isomeric mass lipids within crude lipid extracts, with no requirement for extensive sample handling prior to analysis, with additional potential for enhanced ionization efficiencies, improved molecular level structural characterization, and multiplexed relative quantification. When integrated with a monophasic method for the simultaneous global extraction of both highly polar and nonpolar lipids, this workflow has been shown to enable the sum composition level identification and relative quantification of 500-600 individual lipid species across four lipid categories and from 36 lipid classes and subclasses, in only 1-2 min data acquisition time and with minimal sample consumption. Thus, while some analytical challenges remain to be addressed, shotgun lipidomics workflows encompassing chemical derivatization strategies have particular promise for the analysis of samples with limited availability that require rapid and unbiased assessment of global lipid metabolism.
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Affiliation(s)
- Eileen Ryan
- School
of Chemistry, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Gavin E. Reid
- School
of Chemistry, The University of Melbourne, Parkville, Victoria 3010, Australia
- Department
of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, Victoria 3010, Australia
- Bio21
Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
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33
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Canez CR, Shields SWJ, Bugno M, Wasslen KV, Weinert HP, Willmore WG, Manthorpe JM, Smith JC. Trimethylation Enhancement Using 13C-Diazomethane (13C-TrEnDi): Increased Sensitivity and Selectivity of Phosphatidylethanolamine, Phosphatidylcholine, and Phosphatidylserine Lipids Derived from Complex Biological Samples. Anal Chem 2016; 88:6996-7004. [DOI: 10.1021/acs.analchem.5b04524] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Carlos R. Canez
- Department
of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton
Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Samuel W. J. Shields
- Department
of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton
Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Magdalena Bugno
- Department
of Biology, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Karl V. Wasslen
- Department
of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton
Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Hillary P. Weinert
- Department
of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton
Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - William G. Willmore
- Department
of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Department
of Biology, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Institute
of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Jeffrey M. Manthorpe
- Department
of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Institute
of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton
Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Jeffrey C. Smith
- Department
of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Institute
of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
- Carleton
Mass Spectrometry Centre, Carleton University, Ottawa, Ontario K1S 5B6, Canada
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34
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Cai T, Shu Q, Liu P, Niu L, Guo X, Ding X, Xue P, Xie Z, Wang J, Zhu N, Wu P, Niu L, Yang F. Characterization and relative quantification of phospholipids based on methylation and stable isotopic labeling. J Lipid Res 2016; 57:388-97. [PMID: 26733148 DOI: 10.1194/jlr.m063024] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Indexed: 11/20/2022] Open
Abstract
Phospholipids (PLs), one of the lipid categories, are not only the primary building blocks of cellular membranes, but also can be split to produce products that function as second messengers in signal transduction and play a pivotal role in numerous cellular processes, including cell growth, survival, and motility. Here, we present an integrated novel method that combines a fast and robust TMS-diazomethane-based phosphate derivatization and isotopic labeling strategy, which enables simultaneous profiling and relative quantification of PLs from biological samples. Our results showed that phosphate methylation allows fast and sensitive identification of the six major PL classes, including their lysophospholipid counterparts, under positive ionization mode. The isotopic labeling of endogenous PLs was achieved by deuterated diazomethane, which was generated through acid-catalyzed hydrogen/deuterium (H/D) exchange and methanolysis of TMS-diazomethane during the process of phosphate derivatization. The measured H/D ratios of unlabeled and labeled PLs, which were mixed in known proportions, indicated that the isotopic labeling strategy is capable of providing relative quantitation with adequate accuracy, reproducibility, and a coefficient of variation of 9.1%, on average. This novel method offers unique advantages over existing approaches and presents a powerful tool for research of PL metabolism and signaling.
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Affiliation(s)
- Tanxi Cai
- Laboratory of Protein and Peptide Pharmaceuticals and Laboratory of Proteomics, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Qingbo Shu
- Laboratory of Protein and Peptide Pharmaceuticals and Laboratory of Proteomics, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Peibin Liu
- Laboratory of Protein and Peptide Pharmaceuticals and Laboratory of Proteomics, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Lili Niu
- Department of Biochemistry and Molecular Biology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Xiaojing Guo
- Laboratory of Protein and Peptide Pharmaceuticals and Laboratory of Proteomics, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiang Ding
- Laboratory of Protein and Peptide Pharmaceuticals and Laboratory of Proteomics, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Peng Xue
- Laboratory of Protein and Peptide Pharmaceuticals and Laboratory of Proteomics, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhensheng Xie
- Laboratory of Protein and Peptide Pharmaceuticals and Laboratory of Proteomics, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Jifeng Wang
- Laboratory of Protein and Peptide Pharmaceuticals and Laboratory of Proteomics, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Nali Zhu
- Laboratory of Protein and Peptide Pharmaceuticals and Laboratory of Proteomics, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Peng Wu
- Laboratory of Protein and Peptide Pharmaceuticals and Laboratory of Proteomics, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Lili Niu
- Laboratory of Protein and Peptide Pharmaceuticals and Laboratory of Proteomics, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Fuquan Yang
- Laboratory of Protein and Peptide Pharmaceuticals and Laboratory of Proteomics, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
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35
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Wang M, Wang C, Han RH, Han X. Novel advances in shotgun lipidomics for biology and medicine. Prog Lipid Res 2016; 61:83-108. [PMID: 26703190 PMCID: PMC4733395 DOI: 10.1016/j.plipres.2015.12.002] [Citation(s) in RCA: 192] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 12/01/2015] [Accepted: 12/01/2015] [Indexed: 12/14/2022]
Abstract
The field of lipidomics, as coined in 2003, has made profound advances and been rapidly expanded. The mass spectrometry-based strategies of this analytical methodology-oriented research discipline for lipid analysis are largely fallen into three categories: direct infusion-based shotgun lipidomics, liquid chromatography-mass spectrometry-based platforms, and matrix-assisted laser desorption/ionization mass spectrometry-based approaches (particularly in imagining lipid distribution in tissues or cells). This review focuses on shotgun lipidomics. After briefly introducing its fundamentals, the major materials of this article cover its recent advances. These include the novel methods of lipid extraction, novel shotgun lipidomics strategies for identification and quantification of previously hardly accessible lipid classes and molecular species including isomers, and novel tools for processing and interpretation of lipidomics data. Representative applications of advanced shotgun lipidomics for biological and biomedical research are also presented in this review. We believe that with these novel advances in shotgun lipidomics, this approach for lipid analysis should become more comprehensive and high throughput, thereby greatly accelerating the lipidomics field to substantiate the aberrant lipid metabolism, signaling, trafficking, and homeostasis under pathological conditions and their underpinning biochemical mechanisms.
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Affiliation(s)
- Miao Wang
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute; Orlando, FL 32827, USA
| | - Chunyan Wang
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute; Orlando, FL 32827, USA
| | - Rowland H Han
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute; Orlando, FL 32827, USA
| | - Xianlin Han
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute; Orlando, FL 32827, USA; College of Basic Medical Sciences, Zhejiang Chinese Medical University, 548 Bingwen Road, Hangzhou, Zhejiang 310053, China.
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36
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Profiling and relative quantification of phosphatidylethanolamine based on acetone stable isotope derivatization. Anal Chim Acta 2016; 902:142-153. [DOI: 10.1016/j.aca.2015.11.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 10/15/2015] [Accepted: 11/02/2015] [Indexed: 12/15/2022]
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37
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Yang L, Li M, Shan Y, Shen S, Bai Y, Liu H. Recent advances in lipidomics for disease research. J Sep Sci 2015; 39:38-50. [PMID: 26394722 DOI: 10.1002/jssc.201500899] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 09/14/2015] [Accepted: 09/15/2015] [Indexed: 12/15/2022]
Abstract
Lipidomics is an important branch of metabolomics, which aims at the detailed analysis of lipid species and their multiple roles in the living system. In recent years, the development of various analytical methods for effective identification and characterization of lipids has greatly promoted the process of lipidomics. Meanwhile, as many diseases demonstrate a remarkable alteration in lipid profiles compared with that of healthy people, lipidomics has been extensively introduced to disease research. The comprehensive lipid profiling provides a chance to discover novel biomarkers for specific disease. In addition, it plays a crucial role in the study of lipid metabolism, which could illuminate the pathogenesis of diseases. In this review, after brief discussion of analytical methods for lipidomics in clinical research, we focus on the recent advances of lipidomics related to four types of diseases, including cancer, atherosclerosis, diabetes mellitus, and Alzheimer's disease.
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Affiliation(s)
- Li Yang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Min Li
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Yabing Shan
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, China.,National Research Center for Geoanalysis, Beijing, China
| | - Sensen Shen
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Yu Bai
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Huwei Liu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
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Svane S, Gorshkov V, Kjeldsen F. Charge inversion of phospholipids by dimetal complexes for positive ion-mode electrospray ionization mass spectrometry analysis. Anal Chem 2015; 87:8732-9. [PMID: 26189465 DOI: 10.1021/acs.analchem.5b01536] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Phospholipids are vital constituents of living cells, as they are involved in signaling and membrane formation. Mass spectrometry analysis of many phospholipids is preferentially performed in the negative ion-mode because of their acidic nature. Here we have studied the potential of a digallium and dizinc complex to charge-invert a range of different types of phospholipids and measured their ion yield and fragmentation behavior in positive ion-mode tandem mass spectrometry. The dimetal complexes bind specifically the phosphate groups of phospholipids and add an excess of up to three positive charges per phosphate group. Three different phosphoinositide phosphates (mono-, di-, and triphosphorylated inositides), a phosphatidic acid, a phosphatidylcholine, a phosphatidylethanolamine, and a phosphatidylglycerol were investigated. The intensities obtained in positive ion-mode of phosphoinositide phosphates and phosphatidic acid bound to {LGa2}(5+) were between 2.5- and 116-fold higher than that of the unmodified lipids in the negative ion-mode. Native phosphoinositide ions yielded upon CID in the negative ion-mode predominantly product ions due to losses of H3PO4, PO3(-) and H2O. In comparison, CID spectra of {LGa2}(5+)-bound phosphoinositides generally resulted in fragment ions corresponding to loss of the full diglyceride chain as well as the remaining headgroup bound to {LGa2}(5+) as the most abundant peaks. A number of signature fragment ions of moderate abundance were observed that allowed for distinction between the three regioisomers of 1,2-di(9Z-octadecenoyl)-sn-glycero-3-[phosphoinositol-x,y-bisphosphate] (PI(3,4)P2, PI(3,5)P2, PI(4,5)P2).
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Affiliation(s)
- Simon Svane
- Department of Biochemistry and Molecular Biology, ‡Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , 5230 Odense M, Denmark
| | - Vladimir Gorshkov
- Department of Biochemistry and Molecular Biology, ‡Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , 5230 Odense M, Denmark
| | - Frank Kjeldsen
- Department of Biochemistry and Molecular Biology, ‡Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , 5230 Odense M, Denmark
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