FIG. 5.

Metabolic profiles of the 135 metabolites detected in dataset II in heat map format with hierarchical clustering before normalization (left) and after cyclic-Loess normalization (right). The samples are presented along the x-axis, the 135 detected metabolites are presented along the y-axis; the major classes of metabolites are color coded on the right. The intensity of each metabolite was rescaled between 0 (blue) and 100 (yellow). Before normalization, the clustering algorithm detects the measurement period as group. After normalization, the sensitive and resistant strains are properly separated by the clustering.