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Lin P, W-M Fan T, Lane AN. NMR-based isotope editing, chemoselection and isotopomer distribution analysis in stable isotope resolved metabolomics. Methods 2022; 206:8-17. [PMID: 35908585 PMCID: PMC9539636 DOI: 10.1016/j.ymeth.2022.07.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 07/18/2022] [Accepted: 07/25/2022] [Indexed: 11/20/2022] Open
Abstract
NMR is a very powerful tool for identifying and quantifying compounds within complex mixtures without the need for individual standards or chromatographic separation. Stable Isotope Resolved Metabolomics (or SIRM) is an approach to following the fate of individual atoms from precursors through metabolic transformation, producing an atom-resolved metabolic fate map. However, extracts of cells or tissue give rise to very complex NMR spectra. While multidimensional NMR experiments may partially overcome the spectral overlap problem, additional tools may be needed to determine site-specific isotopomer distributions. NMR is especially powerful by virtue of its isotope editing capabilities using NMR active nuclei such as 13C, 15N, 19F and 31P to select molecules containing just these atoms in a complex mixture, and provide direct information about which atoms are present in identified compounds and their relative abundances. The isotope-editing capability of NMR can also be employed to select for those compounds that have been selectively derivatized with an NMR-active stable isotope at particular functional groups, leading to considerable spectral simplification. Here we review isotope analysis by NMR, and methods of chemoselection both for spectral simplification, and for enhanced isotopomer analysis.
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Affiliation(s)
- Penghui Lin
- Center for Environmental and Systems Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Teresa W-M Fan
- Center for Environmental and Systems Biochemistry, University of Kentucky, Lexington, KY 40536, USA; Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40536, USA
| | - Andrew N Lane
- Center for Environmental and Systems Biochemistry, University of Kentucky, Lexington, KY 40536, USA; Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40536, USA.
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Cox N, Millard P, Charlier C, Lippens G. Improved NMR Detection of Phospho-Metabolites in a Complex Mixture. Anal Chem 2021; 93:4818-4824. [PMID: 33711235 DOI: 10.1021/acs.analchem.0c04056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Phosphorylated metabolites are omnipresent in cells, but their analytical characterization faces several technical hurdles. Here, we detail an improved NMR workflow aimed at assigning the high-resolution subspectrum of the phospho-metabolites in a complex mixture. Combining a pure absorption J-resolved spectrum (Pell, A. J.; J. Magn. Reson. 2007, 189 (2), 293-299) with alternate on- and off-switching of the 31P coupling interaction during the t1 evolution with a pure in-phase (PIP) HSQMBC experiment (Castañar, L.; Angew. Chem., Int. Ed. 2014, 53 (32), 8379-8382) without or with total correlation spectroscopy (TOCSY) transfer during the insensitive nuclei enhancement by polarization transfer (INEPT) gives access to selective identification of the individual subspectra of the phosphorylated metabolites. Returning to the initial J-res spectra, we can extract with optimal resolution the full trace for the individual phospho-metabolites, which can then be transposed on the high-resolution quantitative one dimensional spectrum.
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Affiliation(s)
- Neil Cox
- TBI, Université de Toulouse, CNRS, INRAE, INSA, 31077 Toulouse, France
| | - Pierre Millard
- TBI, Université de Toulouse, CNRS, INRAE, INSA, 31077 Toulouse, France
| | - Cyril Charlier
- TBI, Université de Toulouse, CNRS, INRAE, INSA, 31077 Toulouse, France
| | - Guy Lippens
- TBI, Université de Toulouse, CNRS, INRAE, INSA, 31077 Toulouse, France
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Bhinderwala F, Evans P, Jones K, Laws BR, Smith T, Morton M, Powers R. Phosphorus NMR and Its Application to Metabolomics. Anal Chem 2020; 92:9536-9545. [PMID: 32530272 PMCID: PMC8327684 DOI: 10.1021/acs.analchem.0c00591] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Stable isotopes are routinely employed by NMR metabolomics to highlight specific metabolic processes and to monitor pathway flux. 13C-carbon and 15N-nitrogen labeled nutrients are convenient sources of isotope tracers and are commonly added as supplements to a variety of biological systems ranging from cell cultures to animal models. Unlike 13C and 15N, 31P-phosphorus is a naturally abundant and NMR active isotope that does not require an external supplemental source. To date, 31P NMR has seen limited usage in metabolomics because of a lack of reference spectra, difficulties in sample preparation, and an absence of two-dimensional (2D) NMR experiments, but 31P NMR has the potential of expanding the coverage of the metabolome by detecting phosphorus-containing metabolites. Phosphorylated metabolites regulate key cellular processes, serve as a surrogate for intracellular pH conditions, and provide a measure of a cell's metabolic energy and redox state, among other processes. Thus, incorporating 31P NMR into a metabolomics investigation will enable the detection of these key cellular processes. To facilitate the application of 31P NMR in metabolomics, we present a unified protocol that allows for the simultaneous and efficient detection of 1H-, 13C-, 15N-, and 31P-labeled metabolites. The protocol includes the application of a 2D 1H-31P HSQC-TOCSY experiment to detect 31P-labeled metabolites from heterogeneous biological mixtures, methods for sample preparation to detect 1H-, 13C-, 15N-, and 31P-labeled metabolites from a single NMR sample, and a data set of one-dimensional (1D) 31P NMR and 2D 1H-31P HSQC-TOCSY spectra of 38 common phosphorus-containing metabolites to assist in metabolite assignments.
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Affiliation(s)
- Fatema Bhinderwala
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln NE 68588-0304
- Nebraska Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln NE 68588-0304
| | - Paula Evans
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln NE 68588-0304
| | - Kaleb Jones
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln NE 68588-0304
| | - Benjamin R. Laws
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln NE 68588-0304
| | - Thomas Smith
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln NE 68588-0304
- Nebraska Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln NE 68588-0304
| | - Martha Morton
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln NE 68588-0304
- Nebraska Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln NE 68588-0304
| | - Robert Powers
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln NE 68588-0304
- Nebraska Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln NE 68588-0304
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Prud’homme SM, Hani YMI, Cox N, Lippens G, Nuzillard JM, Geffard A. The Zebra Mussel ( Dreissena polymorpha) as a Model Organism for Ecotoxicological Studies: A Prior 1H NMR Spectrum Interpretation of a Whole Body Extract for Metabolism Monitoring. Metabolites 2020; 10:metabo10060256. [PMID: 32570933 PMCID: PMC7345047 DOI: 10.3390/metabo10060256] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 06/13/2020] [Accepted: 06/16/2020] [Indexed: 01/12/2023] Open
Abstract
The zebra mussel (Dreissena polymorpha) represents a useful reference organism for the ecotoxicological study of inland waters, especially for the characterization of the disturbances induced by human activities. A nuclear magnetic resonance (NMR)-based metabolomic approach was developed on this species. The investigation of its informative potential required the prior interpretation of a reference 1H NMR spectrum of a lipid-free zebra mussel extract. After the extraction of polar metabolites from a pool of whole-body D. polymorpha powder, the resulting highly complex 1D 1H NMR spectrum was interpreted and annotated through the analysis of the corresponding 2D homonuclear and heteronuclear NMR spectra. The spectrum interpretation was completed and validated by means of sample spiking with 24 commercial compounds. Among the 238 detected 1H signals, 53% were assigned, resulting in the identification of 37 metabolites with certainty or high confidence, while 5 metabolites were only putatively identified. The description of such a reference spectrum and its annotation are expected to speed up future analyses and interpretations of NMR-based metabolomic studies on D. polymorpha and to facilitate further explorations of the impact of environmental changes on its physiological state, more particularly in the context of large-scale ecological and ecotoxicological studies.
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Affiliation(s)
- Sophie Martine Prud’homme
- Stress Environnementaux et Biosurveillance des milieux aquatiques, Université Reims Champagne Ardenne, UMR-I 02 SEBIO, 51687 Reims, France;
- LIEC Lab, Université de Lorraine, CNRS, F-57000 Metz, France
- Correspondence: (S.M.P.); (A.G.)
| | - Younes Mohamed Ismail Hani
- Stress Environnementaux et Biosurveillance des milieux aquatiques, Université Reims Champagne Ardenne, UMR-I 02 SEBIO, 51687 Reims, France;
- Université de Bordeaux, UMR EPOC 5805, équipe Ecotoxicologie aquatique, Place du Dr Peyneau, 33120 Arcachon, France
| | - Neil Cox
- Toulouse Biotechnology Institue (TBI), Université de Toulouse, CNRS, INRA, INSA de Toulouse, 135 avenue de Rangueil, 31077 Toulouse CEDEX 04, France; (N.C.); (G.L.)
| | - Guy Lippens
- Toulouse Biotechnology Institue (TBI), Université de Toulouse, CNRS, INRA, INSA de Toulouse, 135 avenue de Rangueil, 31077 Toulouse CEDEX 04, France; (N.C.); (G.L.)
| | - Jean-Marc Nuzillard
- Institut de Chimie Moléculaire, Université de Reims Champagne Ardenne, UMR CNRS 7312 ICMR, 51097 Reims, France;
| | - Alain Geffard
- Stress Environnementaux et Biosurveillance des milieux aquatiques, Université Reims Champagne Ardenne, UMR-I 02 SEBIO, 51687 Reims, France;
- Correspondence: (S.M.P.); (A.G.)
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Lane AN, Higashi RM, Fan TWM. NMR and MS-based Stable Isotope-Resolved Metabolomics and Applications in Cancer Metabolism. Trends Analyt Chem 2018; 120. [PMID: 32523238 DOI: 10.1016/j.trac.2018.11.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
There is considerable interest in defining metabolic reprogramming in human diseases, which is recognized as a hallmark of human cancer. Although radiotracers have a long history in specific metabolic studies, stable isotope-enriched precursors coupled with modern high resolution mass spectrometry and NMR spectroscopy have enabled systematic mapping of metabolic networks and fluxes in cells, tissues and living organisms including humans. These analytical platforms are high in information content, are complementary and cross-validating in terms of compound identification, quantification, and isotope labeling pattern analysis of a large number of metabolites simultaneously. Furthermore, new developments in chemoselective derivatization and in vivo spectroscopy enable tracking of labile/low abundance metabolites and metabolic kinetics in real-time. Here we review developments in Stable Isotope Resolved Metabolomics (SIRM) and recent applications in cancer metabolism using a wide variety of stable isotope tracers that probe both broad and specific aspects of cancer metabolism required for proliferation and survival.
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Affiliation(s)
- Andrew N Lane
- Center for Environmental and Systems Biochemistry, Dept. Toxicology and Cancer Biology, Markey Cancer Center, University of Kentucky, 789 S. Limestone St., Lexington, KY 40536 USA
| | - Richard M Higashi
- Center for Environmental and Systems Biochemistry, Dept. Toxicology and Cancer Biology, Markey Cancer Center, University of Kentucky, 789 S. Limestone St., Lexington, KY 40536 USA
| | - Teresa W-M Fan
- Center for Environmental and Systems Biochemistry, Dept. Toxicology and Cancer Biology, Markey Cancer Center, University of Kentucky, 789 S. Limestone St., Lexington, KY 40536 USA
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Lane AN, Fan TWM. NMR-based Stable Isotope Resolved Metabolomics in systems biochemistry. Arch Biochem Biophys 2017; 628:123-131. [PMID: 28263717 DOI: 10.1016/j.abb.2017.02.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 02/24/2017] [Accepted: 02/27/2017] [Indexed: 01/23/2023]
Abstract
Metabolism is the basic activity of live cells, and monitoring the metabolic state provides a dynamic picture of the cells or tissues, and how they respond to external changes, for in disease or treatment with drugs. NMR is an extremely versatile analytical tool that can be applied to a wide range of biochemical problems. Despite its modest sensitivity its versatility make it an ideal tool for analyzing biochemical dynamics both in vitro and in vivo, especially when coupled with its isotope editing capabilities, from which isotope distributions can be readily determined. These are critical for any analyses of flux in live organisms. This review focuses on the utility of NMR spectroscopy in metabolomics, with an emphasis on NMR applications in stable isotope-enriched tracer research for elucidating biochemical pathways and networks with examples from nucleotide biochemistry. The knowledge gained from this area of research provides a ready link to genomic, epigenomic, transcriptomic, and proteomic information to achieve systems biochemical understanding of living cells and organisms.
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Affiliation(s)
- Andrew N Lane
- Center for Environmental Systems Biochemistry, University of Kentucky, USA; Department of Toxicology and Cancer Biology, University of Kentucky, USA.
| | - Teresa W-M Fan
- Center for Environmental Systems Biochemistry, University of Kentucky, USA; Department of Toxicology and Cancer Biology, University of Kentucky, USA
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Fan TWM, Lane AN. Applications of NMR spectroscopy to systems biochemistry. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2016; 92-93:18-53. [PMID: 26952191 PMCID: PMC4850081 DOI: 10.1016/j.pnmrs.2016.01.005] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 01/26/2016] [Accepted: 01/28/2016] [Indexed: 05/05/2023]
Abstract
The past decades of advancements in NMR have made it a very powerful tool for metabolic research. Despite its limitations in sensitivity relative to mass spectrometric techniques, NMR has a number of unparalleled advantages for metabolic studies, most notably the rigor and versatility in structure elucidation, isotope-filtered selection of molecules, and analysis of positional isotopomer distributions in complex mixtures afforded by multinuclear and multidimensional experiments. In addition, NMR has the capacity for spatially selective in vivo imaging and dynamical analysis of metabolism in tissues of living organisms. In conjunction with the use of stable isotope tracers, NMR is a method of choice for exploring the dynamics and compartmentation of metabolic pathways and networks, for which our current understanding is grossly insufficient. In this review, we describe how various direct and isotope-edited 1D and 2D NMR methods can be employed to profile metabolites and their isotopomer distributions by stable isotope-resolved metabolomic (SIRM) analysis. We also highlight the importance of sample preparation methods including rapid cryoquenching, efficient extraction, and chemoselective derivatization to facilitate robust and reproducible NMR-based metabolomic analysis. We further illustrate how NMR has been applied in vitro, ex vivo, or in vivo in various stable isotope tracer-based metabolic studies, to gain systematic and novel metabolic insights in different biological systems, including human subjects. The pathway and network knowledge generated from NMR- and MS-based tracing of isotopically enriched substrates will be invaluable for directing functional analysis of other 'omics data to achieve understanding of regulation of biochemical systems, as demonstrated in a case study. Future developments in NMR technologies and reagents to enhance both detection sensitivity and resolution should further empower NMR in systems biochemical research.
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Affiliation(s)
- Teresa W-M Fan
- Department of Toxicology and Cancer Biology, University of Kentucky, 789 S. Limestone St., Lexington, KY 40536, United States.
| | - Andrew N Lane
- Department of Toxicology and Cancer Biology, University of Kentucky, 789 S. Limestone St., Lexington, KY 40536, United States.
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Lane AN, Arumugam S, Lorkiewicz PK, Higashi RM, Laulhé S, Nantz MH, Moseley HNB, Fan TWM. Chemoselective detection and discrimination of carbonyl-containing compounds in metabolite mixtures by 1H-detected 15N nuclear magnetic resonance. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2015; 53:337-43. [PMID: 25616249 PMCID: PMC4409496 DOI: 10.1002/mrc.4199] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Revised: 11/08/2014] [Accepted: 11/15/2014] [Indexed: 05/13/2023]
Abstract
NMR spectra of mixtures of metabolites extracted from cells or tissues are extremely complex, reflecting the large number of compounds that are present over a wide range of concentrations. Although multidimensional NMR can greatly improve resolution as well as improve reliability of compound assignments, lower abundance metabolites often remain hidden. We have developed a carbonyl-selective aminooxy probe that specifically reacts with free keto and aldehyde functions, but not carboxylates. By incorporating (15)N in the aminooxy functional group, (15)N-edited NMR was used to select exclusively those metabolites that contain a free carbonyl function while all other metabolites are rejected. Here, we demonstrate that the chemical shifts of the aminooxy adducts of ketones and aldehydes are very different, which can be used to discriminate between aldoses and ketoses, for example. Utilizing the 2-bond or 3-bond (15)N-(1)H couplings, the (15)N-edited NMR analysis was optimized first with authentic standards and then applied to an extract of the lung adenocarcinoma cell line A549. More than 30 carbonyl-containing compounds at NMR-detectable levels, six of which we have assigned by reference to our database. As the aminooxy probe contains a permanently charged quaternary ammonium group, the adducts are also optimized for detection by mass spectrometry. Thus, this sample preparation technique provides a better link between the two structural determination tools, thereby paving the way to faster and more reliable identification of both known and unknown metabolites directly in crude biological extracts.
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Affiliation(s)
- Andrew N Lane
- Center for Regulatory and Environmental Analytical Metabolomics, University of Louisville, Louisville, KY, USA; J.G. Brown Cancer Center, University of Louisville, Louisville, KY, USA
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Matheus N, Hansen S, Rozet E, Peixoto P, Maquoi E, Lambert V, Noël A, Frédérich M, Mottet D, de Tullio P. An easy, convenient cell and tissue extraction protocol for nuclear magnetic resonance metabolomics. PHYTOCHEMICAL ANALYSIS : PCA 2014; 25:342-349. [PMID: 24453161 DOI: 10.1002/pca.2498] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 11/18/2013] [Accepted: 11/24/2013] [Indexed: 06/03/2023]
Abstract
INTRODUCTION As a complement to the classic metabolomics biofluid studies, the visualisation of the metabolites contained in cells or tissues could be a very powerful tool to understand how the local metabolism and biochemical pathways could be affected by external or internal stimuli or pathologies. Therefore, extraction and/or lysis is necessary to obtain samples adapted for use with the current analytical tools (liquid NMR and MS). These extraction or lysis work-ups are often the most labour-intensive and rate-limiting steps in metabolomics, as they require accuracy and repeatability as well as robustness. Many of the procedures described in the literature appear to be very time-consuming and not easily amenable to automation. OBJECTIVE To find a fast, simplified procedure that allows release of the metabolites from cells and tissues in a way that is compatible with NMR analysis. METHODS We assessed the use of sonication to disrupt cell membranes or tissue structures. Both a vibrating probe and an automated bath sonicator were explored. RESULTS The application of sonication as the disruption procedure led to reproducible NMR spectral data compatible with metabolomics studies. This method requires only a small biological tissue or cell sample, and a rapid, reduced work-up was applied before analysis. The spectral patterns obtained are comparable with previous, well-described extraction protocols. CONCLUSION The rapidity and the simplicity of this approach could represent a suitable alternative to the other protocols. Additionally, this approach could be favourable for high- throughput applications in intracellular and intratissular metabolite measurements.
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Affiliation(s)
- Nicolas Matheus
- Metastasis Research Laboratory (MRL), GIGA Cancer, University of Liège, Bat. B23, CHU Sart Tilman, 4000, Liège, Belgium
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Marchione AA, Dooley RJ, Conklin B. Comparison of 1H-19F two-dimensional NMR scalar coupling correlation pulse sequences. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2014; 52:183-189. [PMID: 24535754 DOI: 10.1002/mrc.4052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 01/06/2014] [Accepted: 01/18/2014] [Indexed: 06/03/2023]
Abstract
The effectiveness of hetero-COSY, HETCOR, HMQC, and HSQC two-dimensional NMR pulse sequences for detection of (19)F-(1)H correlations by scalar coupling was evaluated on monofluorinated and polyfluorinated test compounds. All four of these sequences were effective in observing (1)H-(19)F correlations, using either (19) F or (1)H as the observe nucleus. All four sequences were amenable, to some degree, to adjustment to observe larger or smaller couplings preferentially. A 1/2J echo filter was effectively applied to remove artifacts from (2)JFF strong coupling. The HETCOR experiments afforded the best overall combination of sensitivity, resolution and selectivity for JHF.
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Higashi RM, Fan TWM, Lorkiewicz PK, Moseley HNB, Lane AN. Stable isotope-labeled tracers for metabolic pathway elucidation by GC-MS and FT-MS. Methods Mol Biol 2014; 1198:147-67. [PMID: 25270929 DOI: 10.1007/978-1-4939-1258-2_11] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Advances in analytical methodologies, principally nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS), over the last decade have made large-scale analysis of the human metabolome a reality. This is leading to the reawakening of the importance of metabolism in human diseases, particularly widespread metabolic diseases such as cancer, diabetes, and obesity. Emerging NMR and MS atom-tracking technologies and informatics are poised to revolutionize metabolomics-based research because they deliver the high information throughput (HIT) that is needed for deciphering systems biochemistry. In particular, stable isotope-resolved metabolomics (SIRM) enables unambiguous tracking of individual atoms through compartmentalized metabolic networks in a wide range of experimental systems, including human subjects. MS offers a wide range of instrumental capabilities involving different levels of initial capital outlay and operating costs, ranging from gas-chromatography (GC) MS that is affordable by many individual laboratories to the HIT-supporting Fourier-transform (FT) class of MS that rivals NMR in cost and infrastructure support. This chapter focuses on sample preparation, instrument, and data processing procedures for these two extremes of MS instrumentation used in SIRM.
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Affiliation(s)
- Richard M Higashi
- Graduate Center of Toxicology, University of Kentucky, Biopharm Complex, 789 S. Limestone St., Lexington, KY, 40536, USA,
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12
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Considerations of Sample Preparation for Metabolomics Investigation. METHODS IN PHARMACOLOGY AND TOXICOLOGY 2012. [DOI: 10.1007/978-1-61779-618-0_2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
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Principles of NMR for Applications in Metabolomics. METHODS IN PHARMACOLOGY AND TOXICOLOGY 2012. [DOI: 10.1007/978-1-61779-618-0_6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Fan TWM, Lane AN. NMR-based stable isotope resolved metabolomics in systems biochemistry. JOURNAL OF BIOMOLECULAR NMR 2011; 49:267-80. [PMID: 21350847 PMCID: PMC3087304 DOI: 10.1007/s10858-011-9484-6] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Accepted: 11/29/2010] [Indexed: 05/05/2023]
Abstract
An important goal of metabolomics is to characterize the changes in metabolic networks in cells or various tissues of an organism in response to external perturbations or pathologies. The profiling of metabolites and their steady state concentrations does not directly provide information regarding the architecture and fluxes through metabolic networks. This requires tracer approaches. NMR is especially powerful as it can be used not only to identify and quantify metabolites in an unfractionated mixture such as biofluids or crude cell/tissue extracts, but also determine the positional isotopomer distributions of metabolites derived from a precursor enriched in stable isotopes such as (13)C and (15)N via metabolic transformations. In this article we demonstrate the application of a variety of 2-D NMR editing experiments to define the positional isotopomers of compounds present in polar and non-polar extracts of human lung cancer cells grown in either [U-(13)C]-glucose or [U-(13)C,(15)N]-glutamine as source tracers. The information provided by such experiments enabled unambiguous reconstruction of metabolic pathways, which is the foundation for further metabolic flux modeling.
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Affiliation(s)
- Teresa W-M Fan
- Department of Chemistry, University of Louisville, Louisville, KY, USA
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Majumdar A, Sun Y, Shah M, Freel Meyers CL. Versatile (1)H-(31)P-(31)P COSY 2D NMR techniques for the characterization of polyphosphorylated small molecules. J Org Chem 2010; 75:3214-23. [PMID: 20408590 DOI: 10.1021/jo100042m] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Di- and triphosphorylated small molecules represent key intermediates in a wide range of biological and chemical processes. The importance of polyphosphorylated species in biology and medicine underscores the need to develop methods for the detection and characterization of this compound class. We have reported two-dimensional HPP-COSY spectroscopy techniques to identify diphosphate-containing metabolic intermediates at submillimolar concentrations in the methylerythritol phosphate (MEP) isoprenoid biosynthetic pathway. (1) In this work, we explore the scope of HPP-COSY-based techniques to characterize a diverse group of small organic molecules bearing di- and triphosphorylated moieties. These include molecules containing P-O-P and P-C-P connectivities, multivalent P(III)-O-P(V) phosphorus nuclei with widely separated chemical shifts, as well as virtually overlapping (31)P resonances exhibiting strong coupling effects. We also demonstrate the utility of these experiments to rapidly distinguish between mono- and diphosphates. A detailed protocol for optimizing these experiments to achieve best performance is presented.
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Affiliation(s)
- Ananya Majumdar
- The Johns Hopkins University Biomolecular NMR Center, JohnsHopkins School of Medicine, Baltimore, Maryland 21205, USA
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Koskela H. Use of NMR techniques for toxic organophosphorus compound profiling. J Chromatogr B Analyt Technol Biomed Life Sci 2010; 878:1365-81. [DOI: 10.1016/j.jchromb.2009.10.030] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2009] [Revised: 10/25/2009] [Accepted: 10/27/2009] [Indexed: 01/21/2023]
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Fan TWM, Lane AN, Higashi RM, Farag MA, Gao H, Bousamra M, Miller DM. Altered regulation of metabolic pathways in human lung cancer discerned by (13)C stable isotope-resolved metabolomics (SIRM). Mol Cancer 2009; 8:41. [PMID: 19558692 PMCID: PMC2717907 DOI: 10.1186/1476-4598-8-41] [Citation(s) in RCA: 322] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2009] [Accepted: 06/26/2009] [Indexed: 11/30/2022] Open
Abstract
Background Metabolic perturbations arising from malignant transformation have not been systematically characterized in human lung cancers in situ. Stable isotope resolved metabolomic analysis (SIRM) enables functional analysis of gene dysregulations in lung cancer. To this purpose, metabolic changes were investigated by infusing uniformly labeled 13C-glucose into human lung cancer patients, followed by resection and processing of paired non-cancerous lung and non small cell carcinoma tissues. NMR and GC-MS were used for 13C-isotopomer-based metabolomic analysis of the extracts of tissues and blood plasma. Results Many primary metabolites were consistently found at higher levels in lung cancer tissues than their surrounding non-cancerous tissues. 13C-enrichment in lactate, Ala, succinate, Glu, Asp, and citrate was also higher in the tumors, suggesting more active glycolysis and Krebs cycle in the tumor tissues. Particularly notable were the enhanced production of the Asp isotopomer with three 13C-labeled carbons and the buildup of 13C-2,3-Glu isotopomer in lung tumor tissues. This is consistent with the transformations of glucose into Asp or Glu via glycolysis, anaplerotic pyruvate carboxylation (PC), and the Krebs cycle. PC activation in tumor tissues was also shown by an increased level of pyruvate carboxylase mRNA and protein. Conclusion PC activation – revealed here for the first time in human subjects – may be important for replenishing the Krebs cycle intermediates which can be diverted to lipid, protein, and nucleic acid biosynthesis to fulfill the high anabolic demands for growth in lung tumor tissues. We hypothesize that this is an important event in non-small cell lung cancer and possibly in other tumor development.
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Affiliation(s)
- Teresa W M Fan
- Department of Chemistry, University of Louisville, Louisville, Kentucky 40292, USA.
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Majumdar A, Shah MH, Bitok JK, Hassis-LeBeau ME, Freel Meyers CL. Probing phosphorylation by non-mammalian isoprenoid biosynthetic enzymes using (1)H-(31)P-(31)P correlation NMR spectroscopy. MOLECULAR BIOSYSTEMS 2009; 5:935-44. [PMID: 19668858 DOI: 10.1039/b903513c] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The biogenesis of isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP) is accomplished by the methylerythritol phosphate (MEP) pathway in plants, bacteria and parasites, making it a potential target for the development of anti-infective agents and herbicides. The biosynthetic enzymes comprising this pathway catalyze intriguing chemical transformations on diphosphate scaffolds, offering an opportunity to generate novel analogs in this synthetically challenging compound class. Such a biosynthetic approach to generating new diphosphate analogs may involve transformation through discrete diphosphate species, presenting unique challenges in structure determination and characterization of unnatural enzyme-generated diphosphate products produced in tandem. We have developed (1)H-(31)P-(31)P correlation NMR spectroscopy techniques for the direct characterization of crude MEP pathway enzyme products at low concentrations (200 microM to 5 mM) on a room temperature (non-cryogenic) NMR probe. Coupling the 100% natural abundance of the (31)P nucleus with the high intrinsic sensitivity of proton NMR, (1)H-(31)P-(31)P correlation spectroscopy is particularly useful for characterization of unnatural diphosphate enzyme products in the MEP pathway. As proof of principle, we demonstrate the rapid characterization of natural enzyme products of the enzymes IspD, E and F in tandem enzyme incubations. In addition, we have characterized several unnatural enzyme products using this technique, including new products of cytidyltransferase IspD bearing erythritol, glycerol and ribose components. The results of this study indicate that IspD may be a useful biocatalyst and highlight (1)H-(31)P-(31)P correlation spectroscopy as a valuable tool for the characterization of other unnatural products in non-mammalian isoprenoid biosynthesis.
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Affiliation(s)
- Ananya Majumdar
- Biomolecular NMR Center, The Johns Hopkins University, Baltimore, MD 21218, USA.
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Lane AN, Fan TWM, Higashi RM, Tan J, Bousamra M, Miller DM. Prospects for clinical cancer metabolomics using stable isotope tracers. Exp Mol Pathol 2009; 86:165-73. [PMID: 19454273 DOI: 10.1016/j.yexmp.2009.01.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2008] [Indexed: 01/15/2023]
Abstract
Metabolomics provides a readout of the state of metabolism in cells or tissue and their responses to external perturbations. For this reason, the approach has great potential in clinical diagnostics. For more than two decades, we have been using stable isotope tracer approaches to probe cellular metabolism in greater detail. The ability to enrich common compounds with rare isotopes such as carbon ((13)C) and nitrogen ((15)N) is the only practical means by which metabolic pathways can be traced, which entails following the fate of individual atoms from the source molecule to products via metabolic transformation. Changes in regulation of pathways are therefore captured by this approach, which leads to deeper understanding of the fundamental biochemistry of cells. Using lessons learned from pathways tracing in cells and organs, we have been applying this methodology to human cancer patients in a clinical setting. Here we review the methodologies and approaches to stable isotope tracing in cells, animal models and in humans subjects.
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Fan TWM, Kucia M, Jankowski K, Higashi RM, Ratajczak J, Ratajczak MZ, Lane AN. Rhabdomyosarcoma cells show an energy producing anabolic metabolic phenotype compared with primary myocytes. Mol Cancer 2008; 7:79. [PMID: 18939998 PMCID: PMC2577687 DOI: 10.1186/1476-4598-7-79] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2008] [Accepted: 10/21/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The functional status of a cell is expressed in its metabolic activity. We have applied stable isotope tracing methods to determine the differences in metabolic pathways in proliferating Rhabdomysarcoma cells (Rh30) and human primary myocytes in culture. Uniformly 13C-labeled glucose was used as a source molecule to follow the incorporation of 13C into more than 40 marker metabolites using NMR and GC-MS. These include metabolites that report on the activity of glycolysis, Krebs' cycle, pentose phosphate pathway and pyrimidine biosynthesis. RESULTS The Rh30 cells proliferated faster than the myocytes. Major differences in flux through glycolysis were evident from incorporation of label into secreted lactate, which accounts for a substantial fraction of the glucose carbon utilized by the cells. Krebs' cycle activity as determined by 13C isotopomer distributions in glutamate, aspartate, malate and pyrimidine rings was considerably higher in the cancer cells than in the primary myocytes. Large differences were also evident in de novo biosynthesis of riboses in the free nucleotide pools, as well as entry of glucose carbon into the pyrimidine rings in the free nucleotide pool. Specific labeling patterns in these metabolites show the increased importance of anaplerotic reactions in the cancer cells to maintain the high demand for anabolic and energy metabolism compared with the slower growing primary myocytes. Serum-stimulated Rh30 cells showed higher degrees of labeling than serum starved cells, but they retained their characteristic anabolic metabolism profile. The myocytes showed evidence of de novo synthesis of glycogen, which was absent in the Rh30 cells. CONCLUSION The specific 13C isotopomer patterns showed that the major difference between the transformed and the primary cells is the shift from energy and maintenance metabolism in the myocytes toward increased energy and anabolic metabolism for proliferation in the Rh30 cells. The data further show that the mitochondria remain functional in Krebs' cycle activity and respiratory electron transfer that enables continued accelerated glycolysis. This may be a common adaptive strategy in cancer cells.
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Affiliation(s)
- Teresa W M Fan
- Department of Chemistry, University of Louisville, KY, USA.
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Guranowski A, Wojdyła AM, Pietrowska-Borek M, Bieganowski P, Khurs EN, Cliff MJ, Blackburn GM, Błaziak D, Stec WJ. Fhit proteins can also recognize substrates other than dinucleoside polyphosphates. FEBS Lett 2008; 582:3152-8. [PMID: 18694747 DOI: 10.1016/j.febslet.2008.07.060] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2008] [Revised: 07/17/2008] [Accepted: 07/31/2008] [Indexed: 11/26/2022]
Abstract
We show here that Fhit proteins, in addition to their function as dinucleoside triphosphate hydrolases, act similarly to adenylylsulfatases and nucleoside phosphoramidases, liberating nucleoside 5'-monophosphates from such natural metabolites as adenosine 5'-phosphosulfate and adenosine 5'-phosphoramidate. Moreover, Fhits recognize synthetic nucleotides, such as adenosine 5'-O-phosphorofluoridate and adenosine 5'-O-(gamma-fluorotriphosphate), and release AMP from them. With respect to the former, Fhits behave like a phosphodiesterase I concomitant with cleavage of the P-F bond. Some kinetic parameters and implications of the novel reactions catalyzed by the human and plant (Arabidopsis thaliana) Fhit proteins are presented.
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Affiliation(s)
- Andrzej Guranowski
- Department of Biochemistry and Biotechnology, The University of Life Sciences, 60-637 Poznań, Poland.
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Abstract
Nuclear magnetic resonance (NMR) and mass spectrometry (MS) together are synergistic in their ability to profile comprehensively the metabolome of cells and tissues. In addition to identification and quantification of metabolites, changes in metabolic pathways and fluxes in response to external perturbations can be reliably determined by using stable isotope tracer methodologies. NMR and MS together are able to define both positional isotopomer distribution in product metabolites that derive from a given stable isotope-labeled precursor molecule and the degree of enrichment at each site with good precision. Together with modeling tools, this information provides a rich functional biochemical readout of cellular activity and how it responds to external influences. In this chapter, we describe NMR- and MS-based methodologies for isotopomer analysis in metabolomics and its applications for different biological systems.
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Podrabsky JE, Lopez JP, Fan TWM, Higashi R, Somero GN. Extreme anoxia tolerance in embryos of the annual killifishAustrofundulus limnaeus: insights from a metabolomics analysis. J Exp Biol 2007; 210:2253-66. [PMID: 17575031 DOI: 10.1242/jeb.005116] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
SUMMARYThe annual killifish Austrofundulus limnaeus survives in ephemeral pond habitats by producing drought-tolerant diapausing embryos. These embryos probably experience oxygen deprivation as part of their normal developmental environment. We assessed the anoxia tolerance of A. limnaeus embryos across the duration of embryonic development. Embryos develop a substantial tolerance to anoxia during early development, which peaks during diapause II. This extreme tolerance of anoxia is retained during the first 4 days of post-diapause II development and is then lost. Metabolism during anoxia appears to be supported mainly by production of lactate, with alanine and succinate production contributing to a lesser degree. Anoxic embryos also accumulate large quantities of γ-aminobutyrate (GABA), a potential protector of neural function. It appears that the suite of characters associated with normal development and entry into diapause II in this species prepares the embryos for long-term survival in anoxia even while the embryos are exposed to aerobic conditions. This is the first report of such extreme anoxia tolerance in a vertebrate embryo, and introduces a new model for the study of anoxia tolerance in vertebrates.
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Affiliation(s)
- Jason E Podrabsky
- Department of Biology, Portland State University, PO Box 751, Portland, OR 97207-0751, USA.
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Fan TWM, Higashi RM, Lane AN. Integrating metabolomics and transcriptomics for probing SE anticancer mechanisms. Drug Metab Rev 2007; 38:707-32. [PMID: 17145697 DOI: 10.1080/03602530600959599] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Transcriptomics provides the tool for deciphering gene expression networks, and proteomics links these networks to protein products. The third crucial partner is metabolomics, which defines the metabolic network(s) linked to gene expression. NMR and mass spectrometry enable the broad screen analysis of the metabolome and its transformation pathways, transcending classical targeted metabolic studies. These tools were combined to investigate the anticancer mechanisms of different selenium forms in human lung cancer cells. Using 2-D NMR and tandem-MS, we mapped perturbations of 13C labeling patterns in numerous metabolites induced by selenite and selenomethionine. This information was used to interpret selenite-induced changes in gene expression networks. Linking metabolic dysfunctions to altered gene expression profiles provided new insights into the regulatory network underlying the metabolic dysfunctions, enabled the assembly of discrete gene expression events into functional pathways, and revealed protein targets for proteomic analysis.
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Affiliation(s)
- Teresa W-M Fan
- James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky 40202, USA.
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Hubbard JA, MacLachlan LK, Johnson P, Findlow SC, Ladds JC, Lewis CJ, Carter PS, Jones JJ, Fosberry AP. A method for identification of inhibitors of the phosphorylation reactions of bacterial response regulator proteins using (31)P nuclear magnetic resonance spectroscopy. Anal Biochem 2001; 299:31-6. [PMID: 11726181 DOI: 10.1006/abio.2001.5365] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Bacterial response regulators are attractive targets for antibacterial drug development, yet random screening against these targets has failed as yet to identify chemicals that constitute viable leads. Alternative methods to provide leads for drug development based on identification and optimization of low affinity ligands from NMR screens have been described. However, leads from these processes still require verification in a bioassay, which is often problematic if compounds have unfavorable optical and solubility properties. A simple method, based on using NMR to observe the activity of the target, is described. It has the advantages of being able to characterize both low affinity leads and a wider selection of compounds in a structure activity relationships series, without the problems affecting a fluorescence assay. In this example we use (31)P to monitor the turnover of a bacterial response regulator, but the generic approach could be applied to other nuclei and thus a range of biological systems.
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Affiliation(s)
- J A Hubbard
- Computational and Structural Sciences, GlaxoSmithKline, Medicines Research Centre, Gunnels Wood Road, Stevenage, Hertfordshire SG1 2NY, United Kingdom
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Künnecke B, Küstermann E, Seelig J. Simultaneous in vivo monitoring of hepatic glucose and glucose-6-phosphate by (13)C-NMR spectroscopy. Magn Reson Med 2000; 44:556-62. [PMID: 11025511 DOI: 10.1002/1522-2594(200010)44:4<556::aid-mrm9>3.0.co;2-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Hepatic glucose-6-phosphate (G6P) was monitored non-invasively in rat liver by in vivo (13)C NMR spectroscopy after infusion of [1-(13)C] glucose. The phosphorylation of glucose to G6P yields small but characteristic displacements for all of its (13)C-NMR resonances relative to those of glucose. It is demonstrated that in vivo (13)C-NMR spectroscopy at 7 Tesla provides the spectral sensitivity and resolution to detect hepatic G6P present at sub-millimolar concentration as partially resolved low-field shoulders of the glucose C1 resonances at 96.86 ppm (C1beta) and 93. 02 ppm (C1alpha). Upon (13)C-labeling, the intracellular conversion of [1-(13)C] glucose to [1-(13)C] G6P could be monitored, which allowed the hepatic glucose-G6P substrate cycle to be assessed in situ. The close correlation found for the (13)C labeling patterns of glucose and G6P supports the concept of an active substrate cycle whose rate exceeds that of net hepatic glucose metabolism. High-resolution (13)C-NMR spectroscopy and biochemical analyses of tissue biopsies collected at the end of the experiments confirmed qualitatively the findings obtained in vivo.
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Affiliation(s)
- B Künnecke
- Biocenter of the University, Klingelbergstrasse 70, CH-4056 Basel, Switzerland.
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Teleman A, Richard P, Toivari M, Penttilä M. Identification and quantitation of phosphorus metabolites in yeast neutral pH extracts by nuclear magnetic resonance spectroscopy. Anal Biochem 1999; 272:71-9. [PMID: 10405295 DOI: 10.1006/abio.1999.4165] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
(31)P NMR spectroscopy offers a possibility to obtain a survey of all low-molecular-weight phosphorylated compounds in yeast. The yeast cells have been extracted using chloroform into a neutral aqueous phase. The use of high fields and the neutral pH extracts, which are suitable for NMR analysis, results in well-resolved (31)P NMR spectra. Two-dimensional NMR experiments, such as proton-detected heteronuclear single quantum ((1)H-(31)P HSQC) and (31)P correlation spectroscopy ((31)P COSY), have been used to assign the resonances. In the phosphomonoester region many of the signals could be assigned to known metabolites in the glycolytic and pentose phosphate pathways, although some signals remain unidentified. Accumulation of ribulose 5-phosphate, xylulose 5-phosphate, and ribose 5-phosphate was observed in a strain lacking transketolase activity when grown in synthetic complete medium. No such accumulation occurred when the cells were grown in yeast-peptone-dextrose medium. Trimetaphosphate (intracellular concentration about 0.2 mM) was detected in both cold methanol-chloroform and perchloric acid extracts.
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Affiliation(s)
- A Teleman
- VTT Chemical Technology, Espoo, Finland.
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