Partially glucose-capped oligosaccharides are found on the hemoglobins of the deep-sea tube worm Riftia pachyptila.
We report here the structural determination of N-linked oligosaccharides found on extracellular hemoglobins of the hydrothermal vent tube worm Riftia pachyptila. Structures were elucidated by a combination of electrospray ionization tandem mass spectrometry, matrix-assisted laser desorption/ionization mass spectrometry, normal-phase high performance liquid chromatography, and exoglycosidase digestion. The sugar chains were found to consist mainly of high-mannose-type glycans with some structures partially capped by one or two terminal glucose residues. The present study represents the first report of the occurrence of glucose capping of N-linked carbohydrates in a secreted glycoprotein of a metazoan. Previously, glucose capping has only been described for a membrane-bound surface glycoprotein from the unicellular parasite Leishmania mexicana amazonensis.
Zal
F
F
Equipe Ecophysiologie, UPMC-CNRS-INSU, Station Biologique, BP 74, 29682 Roscoff Cedex, France.
Küster
B
B
Green
B N
BN
Harvey
D J
DJ
Lallier
F H
FH
D000818:Animals; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002851:Chromatography, High Pressure Liquid; D005947:Glucose / Q000032:analysis*; D006454:Hemoglobins / Q000737:chemistry* / Q000302:isolation & purification; D007894:Leishmania mexicana; D013058:Mass Spectrometry; D008562:Membrane Glycoproteins / Q000737:chemistry; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry* / Q000302:isolation & purification; D011077:Polychaeta; D015800:Protozoan Proteins / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D006454:Hemoglobins; D008562:Membrane Glycoproteins; D009844:Oligosaccharides; D015800:Protozoan Proteins; D005947:Glucose