Identification of transient glycosylation alterations of sialylated mucin oligosaccharides during infection by the rat intestinal parasite Nippostrongylus brasiliensis.
The sialylation of the oligosaccharides from small-intestinal mucins during a 13-day infectious cycle was studied in Sprague-Dawley rats with the parasite Nippostrongylus brasiliensis. Sialic acid analysis and release, permethylation and analysis by GC-MS of the sialylated oligosaccharides isolated from the 'insoluble' mucin complex revealed a relative decrease (4-7-fold) of N-glycolylneuraminic acid compared with N-acetylneuraminic acid just before parasite expulsion. Northern blots showed that this effect was due to the decreased expression of a hydroxylase converting CMP-N-acetylneuraminic acid into CMP-N-glycolylneuraminic acid. Analysis of other rat strains showed that this parasite infection also caused the same effect in these animals. Detailed analysis of infected Sprague-Dawley rats revealed four sialylated oligosaccharides not found in the uninfected animals. These new oligosaccharides were characterized in detail and all shown to contain the trisaccharide epitope NeuAc/NeuGcalpha2-3(GalNAcbeta1-4)Galbeta1 (where NeuGc is N-glycolyl neuraminic acid). This epitope is similar to the Sd(a)- and Cad-type blood-group antigens and suggests that the infection causes the induction of a GalNAcbeta1-4 glycosyltransferase. This model for an intestinal infection suggests that the glycosylation of intestinal mucins is a dynamic process being modulated by the expression of specific enzymes during an infection process.
Karlsson
N G
NG
Department of Medical Biochemistry, Göteborg University, P.O. Box 440, SE 405 30 Gothenburg, Sweden.
Olson
F J
FJ
Jovall
P A
PA
Andersch
Y
Y
Enerbäck
L
L
Hansson
G C
GC
D000818:Animals; D002240:Carbohydrate Sequence; D008401:Gas Chromatography-Mass Spectrometry; D006031:Glycosylation; D006899:Mixed Function Oxygenases / Q000037:antagonists & inhibitors; D008969:Molecular Sequence Data; D055262:Mucin-2; D009077:Mucins / Q000378:metabolism*; D019158:N-Acetylneuraminic Acid / Q000378:metabolism*; D009559:Nippostrongylus / Q000502:physiology*; D009844:Oligosaccharides / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017206:Strongylida Infections / Q000378:metabolism*
C524628:Muc2 protein, rat; D055262:Mucin-2; D009077:Mucins; D009844:Oligosaccharides; D006899:Mixed Function Oxygenases; C074383:CMPacetylneuraminate monooxygenase; D019158:N-Acetylneuraminic Acid