Glycomic strategy for efficient linkage analysis of di-, oligo- and polysialic acids.
Sialic acid polymers of glycoproteins and glycolipids are characterized by a high diversity in nature and are involved in distinct biological processes depending inter alia on the glycosidic linkages between the present sialic acid residues. Though suitable protocols are available for chain length and sialic acid determination, sensitive methods for linkage analysis of di-, oligo-, and polysialic acids (di/oligo/polySia) are still pending. In this study, we have established a highly sensitive glycomic strategy for this purpose which is based on permethylation of di/oligo/polySia after tagging their reducing ends with the fluorescent dye 1,2-diamino-4,5-methylenedioxybenzene (DMB). Using DMB-labeled sialic acid di/oligo/polymers glycosidic linkages could be efficiently determined and, optionally, the established working procedure can be combined with HPLC for in depth characterization of distinct di/oligo/polySia chains. Moreover, the outlined approach can be directly applied to mammalian tissue samples and linkage analysis of sialic acid polymers present in biopsy samples of neuroblastoma tissue demonstrating the usefulness of the outlined work flow to screen, for example, cancer tissue for the presence of distinct variants of di/oligo/polySia as potentially novel biomarkers. Hence, the described strategy offers a highly sensitive and efficient strategy for identification of glycosidic linkages in sialic acid di/oligo/polymers of glycoproteins and glycolipids.
Institute of Biochemistry, Faculty of Medicine, University of Giessen, Friedrichstrasse 24, D-35392 Giessen, Germany. sebastian.galuska@biochemie.med.uni-giessen.de
Sebastian P
SP
Galuska
Hildegard
H
Geyer
Werner
W
Mink
Peter
P
Kaese
Siegfried
S
Kühnhardt
Benedikt
B
Schäfer
Martina
M
Mühlenhoff
Friedrich
F
Freiberger
Rita
R
Gerardy-Schahn
Rudolf
R
Geyer
D000818:Animals; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D004526:Efficiency / Q000502:physiology; D004926:Escherichia coli; D006017:Glycolipids / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D054794:Glycomics / Q000379:methods*; D006023:Glycoproteins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D051379:Mice; D008954:Models, Biological; D008969:Molecular Sequence Data; D019158:N-Acetylneuraminic Acid / Q000737:chemistry* / Q000378:metabolism*; D058105:Polymerization; D012794:Sialic Acids / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D014407:Tumor Cells, Cultured
D006017:Glycolipids; D006023:Glycoproteins; D012794:Sialic Acids; C021319:polysialic acid; D019158:N-Acetylneuraminic Acid