. Author manuscript; available in PMC: 2011 Sep 3.

Published in final edited form as: J Proteome Res. 2010 Sep 3;9(9):4501–4512. doi: 10.1021/pr1002593

Table 2.

Principal variable loadings p[1] in the GNMTWT/KO PCA model (negative ion data).

Metabolite	p[1] (p[1]cvSE)
PC (20:4/0:0)	−0.25 (0.03)
PC (18:1/0:0)^†	−0.18 (0.03)
PC (16:0/20:4)^†	−0.16 (0.03)
PC (18:2/0:0)	0.26 (0.06)
PC (20:0/0:0)^†	0.14 (0.01)
PC (18:2/18:2)^†	0.14 (0.03)

The standard error of the loading p[1]cvSE generated from the cross-validation rounds is shown in parenthesis.

^†

Metabolite identifications performed by comparison of mass spectra and chromatographic retention times with those obtained using commercially available standards. All other identifications were performed by accurate mass database searching with fragment ion analysis (all mass spectra are available on request). Lipid nomenclature follows the LIPID MAPS convention (www.lipidmaps.org).