Fig. 1.

Transcriptome-directed metabolomics of polyamine metabolism in prostate NEC cells. (A) metaview in silico reconstruction of polyamine metabolism in the KEGG arginine/proline metabolic map. Reconstructions are based upon “Present” calls in GeneChip datasets of PNEC30 cell lines and CR2-TAg prostate tumors. ODC1, ornithine decarboxylase; SRM, spermidine synthase; SMS, spermine synthase. E.C. numbers are in parentheses. (B–E) Mass spectral fragmentation of GABA and polyamines in PNEC cell lines: (B) putrescine ([M+H]⁺ = 89): (C) spermidine ([M+H]⁺ = 146); (D) spermine ([M+H]⁺ = 203); (E) GABA ([M+H]⁺ = 104). [Fragmentation spectra were acquired with an ion trap mass spectrometer and structures assigned to peaks with mass frontier 4.0 (ThermoElectron; see Methods).]