Steryl Glucoside and Acyl Steryl Glucoside Analysis of Arabidopsis Seeds by Electrospray Ionization Tandem Mass Spectrometry
- 681 Downloads
Establishment of sensitive methods for the detection of cellular sterols and their derivatives is a critical step in developing comprehensive lipidomics technology. We demonstrate that electrospray ionization tandem (triple quadrupole) mass spectrometry (ESI-MS/MS) is an efficient method for monitoring steryl glucosides (SG) and acyl steryl glucosides (ASG). Comparison of analysis of SG and ASG by ESI-MS/MS with analysis by gas chromatography with flame ionization detection (GC–FID) shows that the two methods yield similar molar compositions. These data demonstrate that ESI-MS/MS response per molar amount of sterol conjugate is similar among various molecular species of SG and ASG. Application of ESI-MS/MS to seed samples from wild-type Arabidopsis and a mutant deficient in two UDP-glucose:sterol glucosyltransferases, UGT80A2 and UGT80B1, revealed new details on the composition of sitosteryl, campesteryl and stigmasteryl glucosides and ASG. SG were decreased by 86% in the ugt80A2,B1 double mutant, compared to the wild-type, while ASG were reduced 96%. The results indicate that these glucosyltransferases account for much of the accumulation of the sterol conjugates in wild-type Arabidopsis seeds.
KeywordsSteryl glucosides Acyl steryl glucosides Sterols Electrospray ionization tandem mass spectrometry Gas chromatography Arabidopsis thaliana UDP-glucose:sterol glucosyltransferase ugt80A2,B1, UGT80A2, UGT80B1
Acyl steryl glucosides
Electrospray ionization tandem (triple quadrupole) mass spectrometry
Flame ionization detection
K.S. was supported by National Research Initiative Competitive Grants Program grant no. 2007-35304-18453 from the United States Department of Agriculture National Institute of Food and Agriculture and by the National Science Foundation (MCB 0517758). Equipment acquisition and method development at the Kansas Lipidomics Research Center were funded by the National Science Foundation (EPS 0236913, MCB 0455318 and 0920663, DBI 0521587), Kansas Technology Enterprise Corporation, Kansas IDeA Network of Biomedical Research Excellence (K-INBRE) of National Institutes of Health (P20RR16475), and Kansas State University. This is contribution no. 11-374-J from the Kansas Agricultural Experiment Station.
- 8.Heinz E (1996) Plant glycolipids: structure, isolation and analysis. In: Christie WW (ed) Advances in lipid methodology—3. The Oily Press, Dundee, pp 211–332Google Scholar
- 9.Wojciechowski ZA (1991) Biochemistry of phytosterol conjugates. In: Patterson GW, Nes WD (eds) Physiology and biochemistry of sterols. American Oil Chemists Society, Champaign, pp 361–395Google Scholar
- 13.DeBolt S, Scheible WR, Schrick K, Auer M, Beisson F, Bischoff V, Bouvier-Navé P, Carroll A, Hematy K, Li Y, Milne J, Nair M, Schaller H, Zemla M, Somerville C (2009) Mutations in UDP-glucose:sterol glucosyltransferase in Arabidopsis cause transparent testa phenotype and suberization defect in seeds. Plant Physiol 151:78–87PubMedCrossRefGoogle Scholar
- 19.Zhou Z, Marepally SR, Nune DS, Pallakollu P, Ragan G, Roth MR, Wang L, Lushington GH, Visvanathan M, Welti R (2011) LipidomeDB data calculation environment: online processing of direct-infusion mass spectral data for lipid profiles. Lipids 46:879–884Google Scholar