Quantitation of biogenic tetraamines in Arabidopsis thaliana

Classical methods for the determination of polyamines in Arabidopsis, based on high-performance liquid chromatography or thin-layer chromatography, do not distinguish between aliphatic tetraamines or do not allow accurate quantitation, respectively. Here we describe a gas chromatography-mass spectrometry method that allows separation and simple quantitation of spermine and thermospermine. The reliability of the protocol has been confirmed using extracts of Arabidopsis mutants impaired in tetraamine biosynthesis. The levels of thermospermine are around 6-fold lower than those of spermine in Arabidopsis seedlings. Interestingly, hormonal effects on polyamine levels are not always correlated with those of transcripts of their biosynthetic enzymes.