Table 3. New metabolites.

Formula	Carbon labelled	Putative source
C8H16N2O4	5 from arginine, 3 from glucose	l-Ornithine + pyruvate?
C9H18N4O4	6 from arginine, 3 from glucose	l-Arginine + pyruvate?
C8H11NO6S	5 from glutamine, 3 from cysteine	Oxoglutarate + cysteine? Product of an aminotransferase reaction using glutamylcysteine as a substrate?
C10H14N2O7S	5 from glutamine, 3 from cysteine	C8H11NO6S + glycine? Product of an aminotransferase reaction using glutathion as a substrate?
C6H11NO4S	3 from cysteine, 3 from glucose	Cysteine + pyruvate?
C6H9NO4S	3 from cysteine, 3 from glucose	C6H11NO4S–H2?
C8H17NO6S	3 from cysteine, 5 from glucose	Cysteine + pentose?

The formula are assigned based on a measured m/z within 3 ppm of the calculated m/z. No putative identification could be made that would match mass and labelling patterns.