Analysis of Pectin-derived Monosaccharides from Arabidopsis Using GC-MS

Pectin is a complex polysaccharide present in the plant cell wall, whose composition is constantly remodelled to adapt to environmental or developmental changes. Mutants with altered pectin composition have been reported to exhibit altered stress or pathogen resistance. Understanding the link between mutant phenotypes and their pectin composition requires robust analytical methods to detect changes in the relative monosaccharide composition. Here, we describe a quick and efficient gas chromatography-mass spectrometry (GC-MS)-based method that allows the differential analysis of pectin monosaccharide composition in plants under different conditions or between mutant plants and their respective wild types. Pectin is extracted from seed mucilage or from the alcohol-insoluble residue prepared from leaves or other organs and is subsequently hydrolysed with trifluoracetic acid. The resulting acidic and neutral monosaccharides are then derivatised and measured simultaneously by GC-MS.