2 research outputs found
Isotopic Ratio Outlier Analysis Global Metabolomics of Caenorhabditis elegans
We demonstrate the global metabolic
analysis of Caenorhabditis elegans stress
responses using a mass-spectrometry-based
technique called isotopic ratio outlier analysis (IROA). In an IROA
protocol, control and experimental samples are isotopically labeled
with 95 and 5% <sup>13</sup>C, and the two sample populations are
mixed together for uniform extraction, sample preparation, and LC-MS
analysis. This labeling strategy provides several advantages over
conventional approaches: (1) compounds arising from biosynthesis are
easily distinguished from artifacts, (2) errors from sample extraction
and preparation are minimized because the control and experiment are
combined into a single sample, (3) measurement of both the molecular
weight and the exact number of carbon atoms in each molecule provides
extremely accurate molecular formulas, and (4) relative concentrations
of all metabolites are easily determined. A heat-shock perturbation
was conducted on C. elegans to demonstrate
this approach. We identified many compounds that significantly changed
upon heat shock, including several from the purine metabolism pathway.
The metabolomic response information by IROA may be interpreted in
the context of a wealth of genetic and proteomic information available
for C. elegans. Furthermore, the IROA
protocol can be applied to any organism that can be isotopically labeled,
making it a powerful new tool in a global metabolomics pipeline
Isotopic Ratio Outlier Analysis Global Metabolomics of Caenorhabditis elegans
We demonstrate the global metabolic
analysis of Caenorhabditis elegans stress
responses using a mass-spectrometry-based
technique called isotopic ratio outlier analysis (IROA). In an IROA
protocol, control and experimental samples are isotopically labeled
with 95 and 5% <sup>13</sup>C, and the two sample populations are
mixed together for uniform extraction, sample preparation, and LC-MS
analysis. This labeling strategy provides several advantages over
conventional approaches: (1) compounds arising from biosynthesis are
easily distinguished from artifacts, (2) errors from sample extraction
and preparation are minimized because the control and experiment are
combined into a single sample, (3) measurement of both the molecular
weight and the exact number of carbon atoms in each molecule provides
extremely accurate molecular formulas, and (4) relative concentrations
of all metabolites are easily determined. A heat-shock perturbation
was conducted on C. elegans to demonstrate
this approach. We identified many compounds that significantly changed
upon heat shock, including several from the purine metabolism pathway.
The metabolomic response information by IROA may be interpreted in
the context of a wealth of genetic and proteomic information available
for C. elegans. Furthermore, the IROA
protocol can be applied to any organism that can be isotopically labeled,
making it a powerful new tool in a global metabolomics pipeline