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Jurgen Schiller - One of the best experts on this subject based on the ideXlab platform.
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2 5 dihydroxybenzoic acid salts for matrix assisted laser desorption ionization time of flight mass spectrometric Lipid Analysis simplified spectra interpretation and insights into gas phase fragmentation
Rapid Communications in Mass Spectrometry, 2014Co-Authors: Thorsten W Jaskolla, Kristin Onischke, Jurgen SchillerAbstract:RATIONALE In the last decades the interest in Lipids as important components of membranes has considerably increased. Nowadays, Lipids are often routinely analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). In this regard, many relevant aspects are so far unknown, e.g., gas-phase stabilities, adduct formation and fragmentation. To fill this gap, MALDI matrix salts are presented which allow for simplified Lipid Analysis and elucidation of the underlying gas-phase fragmentation mechanisms. METHODS MALDI-TOF MS was used due to its beneficial properties for Lipid investigations, e.g., high sensitivity, simple sample preparations, and a high tolerance to contaminants. The Lipid hydrolysis, ionization and fragmentation properties of synthesized near neutral Na+ and NH4+ salts of the commonly used MALDI matrix 2,5-dihydroxybenzoic acid were compared to that of DHB free acid itself as well as to base addition to DHB during dried-droplet sample preparation. RESULTS Many Lipid classes such as sterols, triacylglycerols, phosphatidylcholines and -ethanolamines undergo initial protonation with subsequent prompt partial up to quantitative fragmentation when analyzed with classical acidic matrices by MALDI-TOF MS. Neutral matrix salts can prevent initial analyte fragmentation by suppression of analyte protonation. Additionally, intramolecular gas-phase fragmentation reactions can be inhibited due to analyte stabilization by cation chelation. Base addition during sample preparation leads not only to in situ generation of matrix salts but also to analyte hydrolysis. CONCLUSIONS Neutral DHB salts avoid separation of Lipid species into several ionization states when used as matrices in MALDI-TOF MS. This allows for simplified Lipid spectra interpretation. Due to the high cationization efficiency of DHB matrix salts, certain Lipid classes become detectable which cannot be analyzed easily using standard acidic DHB. Copyright © 2014 John Wiley & Sons, Ltd.
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leishmania promastigotes lack phosphatidylserine but bind annexin v upon permeabilization or miltefosine treatment
PLOS ONE, 2012Co-Authors: Adrien Weingartner, Jurgen Schiller, Gerdi Christine Kemmer, Frederic D Muller, Ricardo Andrade Zampieri, Marcos Gonzaga Dos Santos, Thomas Gunther PomorskiAbstract:The protozoan parasite Leishmania is an intracellular pathogen infecting and replicating inside vertebrate host macrophages. A recent model suggests that promastigote and amastigote forms of the parasite mimic mammalian apoptotic cells by exposing phosphatidylserine (PS) at the cell surface to trigger their phagocytic uptake into host macrophages. PS presentation at the cell surface is typically analyzed using fluorescence-labeled annexin V. Here we show that Leishmania promastigotes can be stained by fluorescence-labeled annexin V upon permeabilization or miltefosine treatment. However, combined Lipid Analysis by thin-layer chromatography, mass spectrometry and 31 P nuclear magnetic resonance (NMR) spectroscopy revealed that Leishmania promastigotes lack any detectable amount of PS. Instead, we identified several other phosphoLipid classes such phosphatidic acid, phosphatidylethanolamine; phosphatidylglycerol and phosphatidylinositol as candidate Lipids enabling annexin V staining.
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Lipid Analysis by thin layer chromatography a review of the current state
Journal of Chromatography A, 2011Co-Authors: Beate Fuchs, Kristin Teuber, Mandy Eibisch, Jurgen SchillerAbstract:High-performance thin-layer chromatography (HPTLC) is a widely used, fast and relatively inexpensive method of separating complex mixtures. It is particularly useful for smaller, apolar compounds and offers some advantages over HPLC. This review gives an overview about the special features as well as the problems that have to be considered upon the HPTLC Analysis of Lipids. The term “Lipids” is used here in a broad sense and comprises fatty acids and their derivatives as well as substances related biosynthetically or functionally to these compounds. After a short introduction regarding the stationary phases and the methods how Lipids can be visualized on an HPTLC plate, the individual Lipid classes will be discussed and the most suitable solvent systems for their separation indicated. The focus will be on Lipids that are most abundant in biological systems, i.e. cholesterol and its derivates, glycerides, sphingo- and glycoLipids as well as phosphoLipids. Finally, a nowadays very important topic, the combination between HPTLC and mass spectrometric (MS) detection methods will be discussed. It will be shown that this is a very powerful method to investigate the identities of the HPTLC spots in more detail than by the use of common staining methods. Future aspects of HPTLC in the Lipid field will be also discussed.
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MALDI-TOF MS in Lipidomics
Frontiers in Bioscience, 2007Co-Authors: Jurgen SchillerAbstract:So far, matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-TOF MS) seemed to be nearly a synonym for protein Analysis. However, there is growing evidence that this technique is also an useful tool in Lipid Analysis and Lipidomics because of its fast, simple and convenient performance allowing to record mass spectra of cells, crude tissue or body fluid extracts or even intact tissue slices in a few minutes. On the negative side, however, the reproducibility of MALDI-TOF mass spectra depends significantly on the homogeneity of the co-crystals between matrix and analyte and different Lipid classes are detected with different sensitivities. This is especially important because Lipids with quaternary ammonia groups (e.g., GPCho) may prevent the detection of other Lipid classes (e.g., GPEtn). This review starts with a short overview on traditional methods of Lipid Analysis with the focus on mass spectrometric methods and compares MALDI-TOF MS with other important ionization techniques. Afterwards, some landmarks in the development of MALDI-TOF MS will be introduced and some important examples in the field of tissue and body fluid Lipid Analysis will be discussed. This review ends with a short outlook and summary focusing on the advantages and drawbacks of MALDI-TOF MS in Lipidomics.
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matrix assisted laser desorption and ionization time of flight maldi tof mass spectrometry in Lipid and phosphoLipid research
Progress in Lipid Research, 2004Co-Authors: Jurgen Schiller, Rosmarie Suss, Jurgen Arnhold, Beate Fuchs, J Lessig, Matthias M Muller, Marijana Petkovic, Holger Spalteholz, Olaf Zschornig, Klaus ArnoldAbstract:The interest in the Analysis of Lipids and phosphoLipids is continuously increasing due to the importance of these molecules in biochemistry (e.g. in the context of biomembranes and Lipid second messengers) as well as in industry. Unfortunately, commonly used methods of Lipid Analysis are often time-consuming and tedious because they include previous separation and/or derivatization steps. With the development of "soft-ionization techniques" like electrospray ionization (ESI) or matrix-assisted laser desorption and ionization time-of-flight (MALDI-TOF), mass spectrometry became also applicable to Lipid Analysis. The aim of this review is to summarize so far available experiences in MALDI-TOF mass spectrometric Analysis of Lipids. It will be shown that MALDI-TOF MS can be applied to all known Lipid classes and the characteristics of individual Lipids will be discussed. Additionally, some selected applications in medicine and biology, e.g. mixture Analysis, cell and tissue Analysis and the determination of enzyme activities will be described. Advantages and disadvantages of MALDI-TOF MS in comparison to other established Lipid Analysis methods will be also discussed.
Heiko Hayen - One of the best experts on this subject based on the ideXlab platform.
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software tool for mining liquid chromatography multi stage mass spectrometry data for comprehensive glycerophosphoLipid profiling
Rapid Communications in Mass Spectrometry, 2010Co-Authors: Evamaria Hein, Bertram Bodeker, Jurgen Nolte, Heiko HayenAbstract:Electrospray ionization mass spectrometry (ESI-MS) has emerged as an indispensable tool in the field of Lipidomics. Despite the growing interest in Lipid Analysis, there are only a few software tools available for data evaluation, as compared for example to proteomics applications. This makes comprehensive Lipid Analysis a complex challenge. Thus, a computational tool for harnessing the raw data from liquid chromatography/mass spectrometry (LC/MS) experiments was developed in this study and is available from the authors on request. The Profiler-Merger-Viewer tool is a software package for automatic processing of raw-data from data-dependent experiments, measured by high-performance liquid chromatography hyphenated to electrospray ionization hybrid linear ion trap Fourier transform mass spectrometry (FTICR-MS and Orbitrap) in single and multi-stage mode. The software contains three parts: processing of the raw data by Profiler for Lipid identification, summarizing of replicate measurements by Merger and visualization of all relevant data (chromatograms as well as mass spectra) for validation of the results by Viewer. The tool is easily accessible, since it is implemented in Java and uses Microsoft Excel (XLS) as output format. The motivation was to develop a tool which supports and accelerates the manual data evaluation (identification and relative quantification) significantly but does not make a complete data Analysis within a black-box system. The software's mode of operation, usage and options will be demonstrated on the basis of a Lipid extract of baker's yeast (S. cerevisiae). In this study, we focused on three important representatives of Lipids: glycerophosphoLipids, lyso-glycerophosphoLipids and free fatty acids.
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software tool for mining liquid chromatography multi stage mass spectrometry data for comprehensive glycerophosphoLipid profiling
Rapid Communications in Mass Spectrometry, 2010Co-Authors: Evamaria Hein, Bertram Bodeker, Jurgen Nolte, Heiko HayenAbstract:Electrospray ionization mass spectrometry (ESI-MS) has emerged as an indispensable tool in the field of Lipidomics. Despite the growing interest in Lipid Analysis, there are only a few software tools available for data evaluation, as compared for example to proteomics applications. This makes comprehensive Lipid Analysis a complex challenge. Thus, a computational tool for harnessing the raw data from liquid chromatography/mass spectrometry (LC/MS) experiments was developed in this study and is available from the authors on request. The Profiler-Merger-Viewer tool is a software package for automatic processing of raw-data from data-dependent experiments, measured by high-performance liquid chromatography hyphenated to electrospray ionization hybrid linear ion trap Fourier transform mass spectrometry (FTICR-MS and Orbitrap) in single and multi-stage mode. The software contains three parts: processing of the raw data by Profiler for Lipid identification, summarizing of replicate measurements by Merger and visualization of all relevant data (chromatograms as well as mass spectra) for validation of the results by Viewer. The tool is easily accessible, since it is implemented in Java and uses Microsoft Excel (XLS) as output format. The motivation was to develop a tool which supports and accelerates the manual data evaluation (identification and relative quantification) significantly but does not make a complete data Analysis within a black-box system. The software's mode of operation, usage and options will be demonstrated on the basis of a Lipid extract of baker's yeast (S. cerevisiae). In this study, we focused on three important representatives of Lipids: glycerophosphoLipids, lyso-glycerophosphoLipids and free fatty acids. Copyright © 2010 John Wiley & Sons, Ltd.
Beate Fuchs - One of the best experts on this subject based on the ideXlab platform.
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Lipid Analysis by thin layer chromatography a review of the current state
Journal of Chromatography A, 2011Co-Authors: Beate Fuchs, Kristin Teuber, Mandy Eibisch, Jurgen SchillerAbstract:High-performance thin-layer chromatography (HPTLC) is a widely used, fast and relatively inexpensive method of separating complex mixtures. It is particularly useful for smaller, apolar compounds and offers some advantages over HPLC. This review gives an overview about the special features as well as the problems that have to be considered upon the HPTLC Analysis of Lipids. The term “Lipids” is used here in a broad sense and comprises fatty acids and their derivatives as well as substances related biosynthetically or functionally to these compounds. After a short introduction regarding the stationary phases and the methods how Lipids can be visualized on an HPTLC plate, the individual Lipid classes will be discussed and the most suitable solvent systems for their separation indicated. The focus will be on Lipids that are most abundant in biological systems, i.e. cholesterol and its derivates, glycerides, sphingo- and glycoLipids as well as phosphoLipids. Finally, a nowadays very important topic, the combination between HPTLC and mass spectrometric (MS) detection methods will be discussed. It will be shown that this is a very powerful method to investigate the identities of the HPTLC spots in more detail than by the use of common staining methods. Future aspects of HPTLC in the Lipid field will be also discussed.
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matrix assisted laser desorption and ionization time of flight maldi tof mass spectrometry in Lipid and phosphoLipid research
Progress in Lipid Research, 2004Co-Authors: Jurgen Schiller, Rosmarie Suss, Jurgen Arnhold, Beate Fuchs, J Lessig, Matthias M Muller, Marijana Petkovic, Holger Spalteholz, Olaf Zschornig, Klaus ArnoldAbstract:The interest in the Analysis of Lipids and phosphoLipids is continuously increasing due to the importance of these molecules in biochemistry (e.g. in the context of biomembranes and Lipid second messengers) as well as in industry. Unfortunately, commonly used methods of Lipid Analysis are often time-consuming and tedious because they include previous separation and/or derivatization steps. With the development of "soft-ionization techniques" like electrospray ionization (ESI) or matrix-assisted laser desorption and ionization time-of-flight (MALDI-TOF), mass spectrometry became also applicable to Lipid Analysis. The aim of this review is to summarize so far available experiences in MALDI-TOF mass spectrometric Analysis of Lipids. It will be shown that MALDI-TOF MS can be applied to all known Lipid classes and the characteristics of individual Lipids will be discussed. Additionally, some selected applications in medicine and biology, e.g. mixture Analysis, cell and tissue Analysis and the determination of enzyme activities will be described. Advantages and disadvantages of MALDI-TOF MS in comparison to other established Lipid Analysis methods will be also discussed.
Kenji Monde - One of the best experts on this subject based on the ideXlab platform.
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Malabaricone C as Natural Sphingomyelin Synthase Inhibitor against Diet-Induced Obesity and Its Lipid Metabolism in Mice
ACS medicinal chemistry letters, 2019Co-Authors: Muhamad Aqmal Othman, Yuta Murai, Yasuyuki Igarashi, Kohei Yuyama, Daisuke Mikami, Yasodha Sivasothy, Khalijah Awang, Kenji MondeAbstract:The interaction between natural occurring inhibitors and targeted membrane proteins could be an alternative medicinal strategy for the treatment of metabolic syndrome, notably, obesity. In this study, we identified malabaricones A–C and E (1–4) isolated from the fruits of Myristica cinnamomea King as natural inhibitors for sphingomyelin synthase (SMS), a membrane protein responsible for sphingoLipid biosynthesis. Having the most promising inhibition, oral administration of compound 3 exhibited multiple efficacies in reducing weight gain, improving glucose tolerance, and reducing hepatic steatosis in high fat diet-induced obesity mice models. Liver Lipid Analysis revealed a crucial link between the SMS activities of compound 3 and its Lipid metabolism in vitro and in vivo. The nontoxic nature of compound 3 makes it a suitable candidate in search of drugs which can be employed in the treatment and prevention of obesity.
Yu Xia - One of the best experts on this subject based on the ideXlab platform.
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next generation paterno buchi reagents for Lipid Analysis by mass spectrometry
Analytical Chemistry, 2020Co-Authors: Jing Zhao, Xiaobo Xie, Yu XiaAbstract:The Paterno–Buchi (PB) reaction is a photochemical reaction involving [2 + 2] cycloaddition between electronically excited carbonyl and carbon–carbon double bond (C═C). It has been established as a...
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large scale Lipid Analysis with c c location and sn position isomer resolving power
Nature Communications, 2020Co-Authors: Wenbo Cao, Simin Cheng, Jing Yang, Jiaxin Feng, Wenpeng Zhang, Qinhua Chen, Yu Xia, Zheng OuyangAbstract:Lipids play a pivotal role in biological processes and Lipid Analysis by mass spectrometry (MS) has significantly advanced Lipidomic studies. While the structure specificity of Lipid Analysis proves to be critical for studying the biological functions of Lipids, current mainstream methods for large-scale Lipid Analysis can only identify the Lipid classes and fatty acyl chains, leaving the C=C location and sn-position unidentified. In this study, combining photochemistry and tandem MS we develop a simple but effective workflow to enable large-scale and near-complete Lipid structure characterization with a powerful capability of identifying C=C location(s) and sn-position(s) simultaneously. Quantitation of Lipid structure isomers at multiple levels of specificity is achieved and different subtypes of human breast cancer cells are successfully discriminated. Remarkably, human lung cancer tissues can only be distinguished from adjacent normal tissues using quantitative results of both Lipid C=C location and sn-position isomers.
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a method of coupling the paterno buchi reaction with direct infusion esi ms ms for locating the cc bond in glycerophosphoLipids
Analyst, 2016Co-Authors: Craig A Stinso, Yu XiaAbstract:Tandem mass spectrometry (MS/MS) coupled with soft ionization is established as an essential platform for Lipid Analysis; however, determining high order structural information, such as the carbon–carbon double bond (CC) location, remains challenging. Recently, our group demonstrated a method for sensitive and confident Lipid CC location determination by coupling online the Paterno–Buchi (PB) reaction with nanoelectrospray ionization (nanoESI) and MS/MS. Herein, we aimed to expand the scope of the PB reaction for Lipid Analysis by enabling the reaction with infusion ESI-MS/MS at much higher flow rates than demonstrated in the nanoESI setup (∼20 nL min−1). In the new design, the PB reaction was effected in a fused silica capillary solution transfer line, which also served as a microflow UV reactor, prior to ESI. This setup allowed PB reaction optimization and kinetics studies. Under optimized conditions, a maximum of 50% PB reaction yield could be achieved for a standard glycerophosphocholine (PC) within 6 s of UV exposure over a wide flow rate range (0.1–10 μL min−1). A solvent composition of 7 : 3 acetone : H2O (with 1% acid or base modifier) allowed the highest PB yields and good Lipid ionization, while lower yields were obtained with an addition of a variety of organic solvents. Radical induced Lipid peroxidation was identified to induce undesirable side reactions, which could be effectively suppressed by eliminating trace oxygen in the solution via N2 purge. Finally, the utility of coupling the PB reaction with infusion ESI-MS/MS was demonstrated by analyzing a yeast polar Lipid extract where CC bond locations were revealed for 35 glycerophosphoLipids (GPs).
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identification and quantitation of Lipid c c location isomers a shotgun Lipidomics approach enabled by photochemical reaction
Proceedings of the National Academy of Sciences of the United States of America, 2016Co-Authors: Leelyn Chong, Zheng Ouyang, Ran Tian, Riyi Shi, Yu XiaAbstract:The field of Lipidomics has been significantly advanced by mass spectrometric Analysis. The distinction and quantitation of the unsaturated Lipid isomers, however, remain a long-standing challenge. In this study, we have developed an analytical tool for both identification and quantitation of Lipid C=C location isomers from complex mixtures using online Paterno–Buchi reaction coupled with tandem mass spectrometry (MS/MS). The potential of this method has been demonstrated with an implementation into shotgun Lipid Analysis of animal tissues. Among 96 of the unsaturated fatty acids and glycerophosphoLipids identified from rat brain tissue, 50% of them were found as mixtures of C=C location isomers; for the first time, to our knowledge, the quantitative information of Lipid C=C isomers from a broad range of classes was obtained. This method also enabled facile cross-tissue examinations, which revealed significant changes in C=C location isomer compositions of a series of fatty acids and glycerophosphoLipid (GP) species between the normal and cancerous tissues.