The extent of protein N-glycosylation in Leishmania mexicana amazonensis has been proposed to be a factor in the virulence of the parasite. The N-linked oligosaccharides of gp63, the major surface glycoprotein of L. mexicana amazonensis, were characterized after their release by hydrazinolysis, re-N-acetylation, and reduction with NaB3H4. High voltage paper electrophoresis of the reduced oligosaccharides revealed only neutral species. Gel-permeation chromatography on Bio-Gel P-4 yielded four fractions, and the oligosaccharides present were structurally characterized by sequential exoglycosidase digestion, fragmentation by acetolysis, and methylation analysis. Four major structures were found and were biantennary oligomannose type with compositions of Glc1Man6GlcNAc2 (La), Man6GlcNAc2 (Lb), Man5GlcNAc2 (Lc), and Man4 GlcNAc2 (Ld). The largest oligosaccharide (La) was shown to contain a terminal glucopyranosyl residue on the a(1?3) arm. The biantennary oligomannose structures (Lb and Lc) and the glucosylated structure Glc1Man6GlcNAc2 (La) have not previously been reported as a component of a mature glycoprotein from any source.
|Number of pages||8|
|Journal||Journal of Biological Chemistry|
|Publication status||Published - 25 Jul 1990|