Structural characterization of unsaturated glycerophospholipids by multiple-stage linear ion-trap mass spectrometry with electrospray ionization.
Structural elucidation of glycerophospholipids (GPLs), including the polar head group, the position of double-bond(s) along the fatty acyl substituents, and the positions of acyl groups on the glycerol backbone, using multiple-stage liner ion-trap (LIT) mass spectrometric approach is described in this paper. While the product-ion spectra from MSn (n=2, 3) on the [M+Li]+ or [M-H+2Li]+ ions of GPL are readily applicable for discerning the phospholipid classes and for identifying and locating the fatty acid substituents on the glycerol backbone, the structural information from further dissociation of the dilithiated fatty acid cations produced from MSn (n=3, 4) on the [M-H+2Li]+ ion of GPLs, as well as from further dissociation of the monolithiated fragment ion that bears the unsaturated fatty acid moiety produced from subsequent MSn (n=3,4) on the [M+Li]+ ions of GPLs, affords assignment of the position of double-bond(s) along the fatty acyl groups. The application of the present method in the structural characterization of GPL molecules from the lipid extracts of biological origin, including mixtures of phosphatidylglycerol and of phosphatidylserine without prior chromatographic separation, is also demonstrated. Since lithiated molecular species of GPL are readily formed by ESI, this multiple-stage LIT mass spectrometric approach provides a direct means for the near-complete structural characterization of all the GPLs, including the molecules in the lysophospholipid and plasmalogen subclasses.
Hsu
Fong-Fu
FF
Mass Spectrometry Resource, Division of Endocrinology, Diabetes, Metabolism, and Lipid Research, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA. fhsu@im.wustl.edu
Turk
John
J
D000818:Animals; D004926:Escherichia coli / Q000737:chemistry; D020404:Glycerophospholipids / Q000737:chemistry*; D008094:Lithium / Q000737:chemistry; D010712:Phosphatidic Acids / Q000737:chemistry; D010713:Phosphatidylcholines / Q000737:chemistry; D010714:Phosphatidylethanolamines / Q000737:chemistry; D010716:Phosphatidylinositols / Q000032:analysis / Q000737:chemistry; D010718:Phosphatidylserines / Q000737:chemistry; D013025:Glycine max / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
D020404:Glycerophospholipids; D010712:Phosphatidic Acids; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010716:Phosphatidylinositols; D010718:Phosphatidylserines; D008094:Lithium
J Am Soc Mass Spectrom. 2007 Sep;18(9):1591-604
17627842
J Mass Spectrom. 2003 Jul;38(7):752-63
12898655
Anal Chem. 2008 Jan 1;80(1):303-11
18062677
J Am Soc Mass Spectrom. 2008 Nov;19(11):1673-80
18692406
J Am Soc Mass Spectrom. 1999 Jul;10(7):600-12
10384724
J Am Soc Mass Spectrom. 2003 Apr;14(4):352-63
12686482
J Am Soc Mass Spectrom. 1999 Jul;10(7):587-99
10384723
J Mass Spectrom. 2000 May;35(5):595-606
10800048
Rapid Commun Mass Spectrom. 2004;18(18):2121-30
15317043
J Am Chem Soc. 2006 Jan 11;128(1):58-9
16390120
J Am Soc Mass Spectrom. 2005 Jan;16(1):46-59
15653363
Mass Spectrom Rev. 2003 Sep-Oct;22(5):332-64
12949918
Anal Chem. 2007 Jul 1;79(13):5013-22
17547368
J Am Soc Mass Spectrom. 2005 Sep;16(9):1510-1522
16023863
Anal Chem. 1996 Sep 15;68(18):3224-30
8797383