Metabolic networks of Cucurbita maxima phloem

Oliver Fiehn

Research output: Contribution to journalArticle

118 Citations (Scopus)

Abstract

Metabolomic analysis aims at a comprehensive characterization of biological samples. Yet, biologically meaningful interpretations are often limited by the poor spatial and temporal resolution of the acquired data sets. One way to remedy this is to limit the complexity of the cell types being studied. Cucurbita maxima Duch. vascular exudates provide an excellent material for metabolomics in this regard. Using automated mass spectral deconvolution, over 400 components have been detected in these exudates, but only 90 of them were tentatively identified. Many amino compounds were found in vascular exudates from leaf petioles at concentrations several orders of magnitude higher than in tissue disks from the same leaves, whereas hexoses and sucrose were found in far lower amounts. In order to find the expected impact of assimilation rates on sugar levels, total phloem composition of eight leaves from four plants was followed over 4.5 days. Surprisingly, no diurnal rhythm was found for any of the phloem metabolites that was statistically valid for all eight leaves. Instead, each leaf had its own distinct vascular exudate profile similar to leaves from the same plant, but clearly different from leaves harvested from plants at the same developmental stage. Thirty to forty per cent of all metabolite levels of individual leaves were different from the average of all metabolite profiles. Using metabolic co-regulation analysis, similarities and differences between the exudate profiles were more accurately characterized through network computation, specifically with respect to nitrogen metabolism.

Original languageEnglish (US)
Pages (from-to)875-886
Number of pages12
JournalPhytochemistry
Volume62
Issue number6
DOIs
StatePublished - Mar 2003
Externally publishedYes

Fingerprint

Phloem
Cucurbita
Cucurbita maxima
Exudates and Transudates
Metabolites
Metabolic Networks and Pathways
phloem
Plant Leaves
Blood Vessels
Metabolomics
leaves
Hexoses
blood vessels
Deconvolution
Metabolism
Sugars
Sucrose
metabolomics
Nitrogen
metabolites

Keywords

  • Companion cells
  • Cucurbita maxima
  • Cucurbitaceae
  • Extrafascicular phloem
  • GC/MS
  • LC/MS
  • Mass spectrometry
  • Metabolite profiling
  • Sieve elements

ASJC Scopus subject areas

  • Plant Science
  • Biochemistry
  • Molecular Biology
  • Organic Chemistry
  • Drug Discovery

Cite this

Metabolic networks of Cucurbita maxima phloem. / Fiehn, Oliver.

In: Phytochemistry, Vol. 62, No. 6, 03.2003, p. 875-886.

Research output: Contribution to journalArticle

Fiehn, Oliver. / Metabolic networks of Cucurbita maxima phloem. In: Phytochemistry. 2003 ; Vol. 62, No. 6. pp. 875-886.
@article{15167b1afbe84b9e8f9642b51bb7bc5d,
title = "Metabolic networks of Cucurbita maxima phloem",
abstract = "Metabolomic analysis aims at a comprehensive characterization of biological samples. Yet, biologically meaningful interpretations are often limited by the poor spatial and temporal resolution of the acquired data sets. One way to remedy this is to limit the complexity of the cell types being studied. Cucurbita maxima Duch. vascular exudates provide an excellent material for metabolomics in this regard. Using automated mass spectral deconvolution, over 400 components have been detected in these exudates, but only 90 of them were tentatively identified. Many amino compounds were found in vascular exudates from leaf petioles at concentrations several orders of magnitude higher than in tissue disks from the same leaves, whereas hexoses and sucrose were found in far lower amounts. In order to find the expected impact of assimilation rates on sugar levels, total phloem composition of eight leaves from four plants was followed over 4.5 days. Surprisingly, no diurnal rhythm was found for any of the phloem metabolites that was statistically valid for all eight leaves. Instead, each leaf had its own distinct vascular exudate profile similar to leaves from the same plant, but clearly different from leaves harvested from plants at the same developmental stage. Thirty to forty per cent of all metabolite levels of individual leaves were different from the average of all metabolite profiles. Using metabolic co-regulation analysis, similarities and differences between the exudate profiles were more accurately characterized through network computation, specifically with respect to nitrogen metabolism.",
keywords = "Companion cells, Cucurbita maxima, Cucurbitaceae, Extrafascicular phloem, GC/MS, LC/MS, Mass spectrometry, Metabolite profiling, Sieve elements",
author = "Oliver Fiehn",
year = "2003",
month = "3",
doi = "10.1016/S0031-9422(02)00715-X",
language = "English (US)",
volume = "62",
pages = "875--886",
journal = "Phytochemistry",
issn = "0031-9422",
publisher = "Elsevier Limited",
number = "6",

}

TY - JOUR

T1 - Metabolic networks of Cucurbita maxima phloem

AU - Fiehn, Oliver

PY - 2003/3

Y1 - 2003/3

N2 - Metabolomic analysis aims at a comprehensive characterization of biological samples. Yet, biologically meaningful interpretations are often limited by the poor spatial and temporal resolution of the acquired data sets. One way to remedy this is to limit the complexity of the cell types being studied. Cucurbita maxima Duch. vascular exudates provide an excellent material for metabolomics in this regard. Using automated mass spectral deconvolution, over 400 components have been detected in these exudates, but only 90 of them were tentatively identified. Many amino compounds were found in vascular exudates from leaf petioles at concentrations several orders of magnitude higher than in tissue disks from the same leaves, whereas hexoses and sucrose were found in far lower amounts. In order to find the expected impact of assimilation rates on sugar levels, total phloem composition of eight leaves from four plants was followed over 4.5 days. Surprisingly, no diurnal rhythm was found for any of the phloem metabolites that was statistically valid for all eight leaves. Instead, each leaf had its own distinct vascular exudate profile similar to leaves from the same plant, but clearly different from leaves harvested from plants at the same developmental stage. Thirty to forty per cent of all metabolite levels of individual leaves were different from the average of all metabolite profiles. Using metabolic co-regulation analysis, similarities and differences between the exudate profiles were more accurately characterized through network computation, specifically with respect to nitrogen metabolism.

AB - Metabolomic analysis aims at a comprehensive characterization of biological samples. Yet, biologically meaningful interpretations are often limited by the poor spatial and temporal resolution of the acquired data sets. One way to remedy this is to limit the complexity of the cell types being studied. Cucurbita maxima Duch. vascular exudates provide an excellent material for metabolomics in this regard. Using automated mass spectral deconvolution, over 400 components have been detected in these exudates, but only 90 of them were tentatively identified. Many amino compounds were found in vascular exudates from leaf petioles at concentrations several orders of magnitude higher than in tissue disks from the same leaves, whereas hexoses and sucrose were found in far lower amounts. In order to find the expected impact of assimilation rates on sugar levels, total phloem composition of eight leaves from four plants was followed over 4.5 days. Surprisingly, no diurnal rhythm was found for any of the phloem metabolites that was statistically valid for all eight leaves. Instead, each leaf had its own distinct vascular exudate profile similar to leaves from the same plant, but clearly different from leaves harvested from plants at the same developmental stage. Thirty to forty per cent of all metabolite levels of individual leaves were different from the average of all metabolite profiles. Using metabolic co-regulation analysis, similarities and differences between the exudate profiles were more accurately characterized through network computation, specifically with respect to nitrogen metabolism.

KW - Companion cells

KW - Cucurbita maxima

KW - Cucurbitaceae

KW - Extrafascicular phloem

KW - GC/MS

KW - LC/MS

KW - Mass spectrometry

KW - Metabolite profiling

KW - Sieve elements

UR - http://www.scopus.com/inward/record.url?scp=0037370412&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0037370412&partnerID=8YFLogxK

U2 - 10.1016/S0031-9422(02)00715-X

DO - 10.1016/S0031-9422(02)00715-X

M3 - Article

C2 - 12590115

AN - SCOPUS:0037370412

VL - 62

SP - 875

EP - 886

JO - Phytochemistry

JF - Phytochemistry

SN - 0031-9422

IS - 6

ER -