Quantitation of ceramide phosphorylethanolamines containing saturated and unsaturated sphingoid base cores.
Sphingomyelin (SM) and ceramide-phosphoethanolamines (cer-PEs) are related lipids present in mammals and insects, respectively. Owing to the critical roles that cer-PEs play in eukaryotic cellular function, there is a need to develop methods that provide accurate quantitation of these compounds. Results obtained in this study demonstrate that Drosophila contains cer-PEs with unsaturated sphingoid base cores as well as low levels of cer-PEs that possess saturated sphingoid base cores. Specifically, the method developed in this study enabled the quantitation of picogram amounts of cer-PE containing both unsaturated d14:1(Delta4) and d16:1(Delta4) and saturated d14:0 sphingoid base cores. Using this method, cer-PE compounds with both saturated and unsaturated sphingoid base cores were initially identified by neutral loss scanning, followed by quantitation using selected reaction monitoring (SRM) scans. The SRM scans measured a product ion originating from the sphingoid base backbone, rather than from the head group, increasing the specificity and sensitivity of the quantitation measurement.
Masood
M Athar
MA
Laboratory of Proteomics and Analytical Technologies, Advanced Technology Program, SAIC-Frederick, NCI-Frederick, Frederick, MD 21702, USA. masoodaa@mail.nih.gov
Yuan
Changqing
C
Acharya
Jairaj K
JK
Veenstra
Timothy D
TD
Blonder
Josip
J
D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D056148:Chromatography, Reverse-Phase; D004330:Drosophila / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013109:Sphingomyelins / Q000032:analysis* / Q000737:chemistry
D013109:Sphingomyelins; C060281:ceramide phosphoethanolamine