Consistency analysis of metabolic correlation networks.
BACKGROUND
Metabolic correlation networks are derived from the covariance of metabolites in replicates of metabolomics experiments. They constitute an interesting intermediate between topology (i.e. the system's architecture defined by the set of reactions between metabolites) and dynamics (i.e. the metabolic concentrations observed as fluctuations around steady-state values in the metabolic network).


RESULTS
Here we analyze, how such a correlation network changes over time, and compare the relative positions of metabolites in the correlation networks with those in established metabolic networks derived from genome databases. We find that network similarity indeed decreases with an increasing time difference between these networks during a day/night course and, counter intuitively, that proximity of metabolites in the correlation network is no indicator of proximity of the metabolites in the metabolic network.


CONCLUSIONS
The organizing principles of correlation networks are distinct from those of metabolic reaction maps. Time courses of correlation networks may in the future prove an important data source for understanding these organizing principles.
Müller-Linow
Mark
M
Bioinformatics Group, Department of Biology, Darmstadt University of Technology, 64287 Darmstadt, Germany. muellerlinow@bio.tu-darmstadt.de
Weckwerth
Wolfram
W
Hütt
Marc-Thorsten
MT
D000596:Amino Acids / Q000737:chemistry; D017360:Arabidopsis / Q000378:metabolism*; D002241:Carbohydrates / Q000737:chemistry; D015698:Genomic Library; D053858:Metabolic Networks and Pathways; D008954:Models, Biological; D013997:Time Factors
D000596:Amino Acids; D002241:Carbohydrates